Leave the repairs and renovations of condominiums and apartments in Koganei City, Tokyo to Kakeru Koumuten Co., Ltd.!
Large-Scale Renovations for Condominiums, Apartments, and Buildings in Koganei City, Tokyo
To owners, management associations, and management companies considering large-scale renovations for condominiums, apartments, and buildings in Koganei City, Tokyo.
Kakeru Koumuten Co., Ltd. is a company that handles everything from the installation of temporary scaffolding to substrate repairs, exterior painting, tile repairs, sealing, waterproofing for roofs and balconies, and roofing work, all managed and performed by our own team. We have undertaken numerous large-scale renovations and exterior reforms for apartments, condominiums, and commercial facilities in Koganei City.
- On-site inspections and estimates are completely free (we welcome competitive estimates)
- All work from temporary scaffolding to exterior and roofing work is managed by our own team
- Our own scaffolding team handles sites in Koganei City, from condominiums to apartments
- Consultations for partial repairs and emergency measures for leaks are also possible
- Cost Estimate / For condominiums, the cost per unit is 750,000 to 1,500,000 JPY (according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for fiscal year 2021, about 70% fall within this range, with the most common being 1,000,000 to 1,250,000 JPY. This amount excludes consumption tax and common temporary costs). For wooden apartments, the estimate is 2,000,000 to 4,000,000 JPY per building.
- Estimated Cycle / 12 to 15 years. However, the deciding factor is not the number of years but the condition of deterioration.
- Particularly Relevant in Koganei City / According to a survey by Tokyo (published in March 2013), there are 202 condominium buildings in the city, of which 34 are classified as old seismic standards. The city’s actual survey (from 2010) indicates that the most common construction years are from Heisei 3 to 12 (63 cases, 35.2%), suggesting a significant number of buildings are between 26 to 45 years old. The city has a height difference of about 35 meters due to the Kokubunji Cliff Line, and approximately 95% of the land use is residential. If scaffolding extends over the road, the opinion of the Koganei Police Station is essential for the sidewalk, and there are standards for the extent of the projection. Regarding aesthetics, there is no confirmation of a unique city landscape plan, and notification under the Tokyo Metropolitan Landscape Ordinance and changes in form and design in district planning areas are points of discussion.
- Available Funding / The official page of Koganei City does not confirm any municipal systems that subsidize the construction costs or deterioration diagnosis costs for large-scale renovations. The city provides information on management plan certification, management status reporting, and condominium management improvement plans. If requirements are met, there is a one-third reduction special exception on fixed asset tax (for Koganei City taxes. Work must be completed by March 31, 2027, and reported within three months after completion), interest subsidies from Tokyo (applications for the second phase of fiscal year 2026 are accepted until February 19, 2027), and consideration of public financing. The city’s subsidy for the promotion of new energy equipment for residential use is for individuals, and applications for fiscal year 2026 have already closed.
- Tips to Avoid Mistakes / At least three competitive estimates. Compare not only the amounts but also the quantities, methods, and materials.
Large-scale repair work available in Koganei City, Tokyo
Large-scale repairs are not just “exterior painting” or “waterproofing,” but a comprehensive project to address the deterioration of the entire building while scaffolding is in place. At Kakeru Koumuten, we can handle all of the following work with our own team, ensuring clear responsibility and coordination of the process.
| Type of Work | Main Contents |
|---|---|
| Temporary Scaffolding Work | Installed by our own scaffolding team using our own scaffolding materials. We handle mesh sheets, protection, and fall prevention measures. |
| Substrate Repair Work | Crack repairs, injection of floating mortar and tiles, explosion (exposed rebar) repairs, resin mortar repairs for missing parts. |
| Exterior Wall Painting Work | High-pressure washing, three coats from primer to topcoat, painting of auxiliary parts (iron parts, gutters, water cut-offs, etc.). We accommodate radical control type, fluorine, and inorganic paints. |
| Tile Repair Work | Replacement of broken tiles, joint repairs, clear waterproofing of tile surfaces (such as Seven S). |
| Sealing Work | Re-sealing around sashes and exterior wall joints, additional sealing. |
| Waterproofing Work | Urethane waterproofing for rooftops, roof balconies, shared corridors, and stairs, PVC sheet waterproofing, and installation of long sheets. |
| Roof Work | Roof painting, roof overlay (cover method), re-roofing, and ridge cap replacement. We have sheet metal craftsmen on staff and can handle large roofs such as factories. |
| Metal and Hardware Work | Painting of steel staircases, handrails, and PS doors, replacement of coping and water cut-offs. |
| Drainage and Wastewater Work | Cleaning and renovation of roof drains (insertion of renovation drains), resolving gutter blockages. Drainage issues can cause puddles and leaks, making this work particularly important for buildings with rooftops. |
| Others | Replacement of rain gutters, rooftop and exterior wall inspections using drones, leak investigations using thermography, and preliminary surveys of asbestos-containing building materials. |
Scope of Major Repairs Determined from Building Diagnosis
It is not always necessary to carry out all of the above works. The extent of the work will be determined based on the results of the building diagnosis. At Kakeru Koumuten Co., Ltd., we conduct a free on-site survey to confirm the following and summarize it in a deterioration diagnosis report with photos, after which we will propose the scope of work.
| Diagnosis Area | Main Investigation Method | Scope of Work Determined by Diagnosis Results |
|---|---|---|
| Exterior Wall (Painted Surface) | Visual inspection, checking the width of cracks and the condition of the paint film | Method and quantity of crack repairs, specifications for painting (whether to repaint or paint after removing the existing paint film) |
| Exterior Wall (Tile Surface) | Sounding investigation. High areas checked with a drone | Scope and estimated quantity for injection and replacement, whether clear waterproofing is necessary |
| Sealing | Checking for cracks, shrinkage, peeling, and hardening | Whether to replace or add to the existing seal, scope of joints to be worked on |
| Rooftop, Balcony, Shared Corridor | Checking for blisters or breaks in the waterproof layer, puddles, and the condition of drains | Full renovation or partial repair, method (urethane waterproofing, PVC sheet waterproofing, long sheet), whether drain renovation is necessary |
| Leak Areas | Investigation using thermal imaging camera and drone | Identification of the cause and the priority areas for repair |
| Metal Parts, Roof, Auxiliary Parts | Checking for rust, corrosion, lifting, and cracking | Whether it can be resolved with painting or if material replacement or overlay installation is necessary |
| Site and Surroundings | Checking retaining walls, slopes, trees, delivery routes, and parking areas | Planning for scaffolding and the scope of temporary construction |
Reasons Kakeru Koumuten is Chosen for Large-Scale Renovations in Koganei City, Tokyo
The reason why we can be entrusted with large-scale repairs in Koganei City is due to our “initiatives that cannot be imitated by other companies in large-scale repair work”, which have been well received by many customers.
1. Equipment Specialized for Exterior Renovations
At Kakeru Koumuten, we have prepared the following warehouses and material storage areas to provide exterior wall painting and waterproofing work for large-scale repairs at low cost and high quality. We have established five bases centered around Yokohama City for material storage and showrooms.
In-house Ownership of Scaffolding Materials
We own the scaffolding materials necessary for temporary scaffolding required for large-scale repairs and can assemble the scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can reduce the cost of scaffolding work and enable quick and flexible responses.
We have approximately enough scaffolding materials for 100 single-family homes!
Storage of Materials in Our Large In-house Warehouse
We store paints and substrate repair materials used for exterior renovations. By ordering a large quantity of materials at once, we canprocure materials at a lower cost! Additionally, we always have stock available, allowing for speedy responses in emergencies!
In-house Sorting of Waste Materials
Large-scale repairs generate various waste materials such as waste paint, metals, and wood. At Kakeru Koumuten, we sort and recycle waste materials in-house, leading to cost reductions in waste disposal fees.
Showroom Dedicated to Exterior Renovations
In the showroom, you can not only have meetings but also check actual samples and colors of exterior materials. Color simulations for exterior wall painting and confirmation of heat insulation properties using a heat insulation testing machine are also available!
2. Cost Reduction through In-House Management and Construction
One of Kakeru Koumuten’s major strengths is in-house management and construction.
By managing everything from inquiries to project completion in a consistent system, we can keep costs down while providing high-quality large-scale repairs. Additionally, one representative will handle everything from the estimate to project completion. Since the person in charge does not change, whether it’s sales or construction management, smooth communication is possible.
We can handle everything from temporary scaffolding installation to exterior wall painting, substrate repairs, waterproofing work, and tile repairs with complete in-house construction! Those with specialized knowledge and experience conduct inspections and actual construction for each process!
3. Obtaining Various Permits and Skilled Workers
We have obtained construction business licenses and permits for industrial waste collection and transportation! We also have nationally certified sheet metal and painting skilled workers, and we are confident in our construction techniques. We can also handle large-scale roofing work for factories! We have qualified personnel for asbestos work supervisors and building materials containing asbestos inspectors, so we can handle and conduct preliminary investigations on roofing materials containing asbestos.
4. Warranty and Aftercare
Most large-scale repair works, including “painting work,” “substrate repair work,” and “waterproofing work,” come with a warranty!
Aftercare maintenance is available every year, and we send out notification DM annually.
5. Flexible and Prompt Response
Our company is equipped to handle various troubles and situations related to apartments and condominiums.
We can also address exterior walls and rooftops that cannot be checked from high places using drones! During leak investigations, we can use a thermal imaging camera to help identify the cause of leaks!
We will respond according to your wishes. We also accept emergency measures for sudden leaks! We will promptly respond to urgent requests and emergencies!
6. Staff Development
Our staff create various models for skill improvement and conduct practical training. Since different sites require various processing and techniques, we regularly provide skill enhancement education to ensure each staff member can respond effectively. We also educate on points to be careful about and areas to check in each process of large-scale repair works.
7. Consideration for Residents and Neighbors
During large-scale renovation work, we will not only notify residents and greet nearby residents, but also install notice boards at the entrance to display the construction schedule and announcements! Additionally, we will thoroughly educate entrants on manners to minimize any inconvenience to residents and neighbors.
8. Strict Quality Control
Each process will be inspected by a responsible person, and detailed construction photos will be taken. We will use film thickness inspection machines and check sheets to ensure that there are no oversights in inspections. During exterior wall painting and waterproofing work, we will check the number of used paint cans to confirm that the specified amount of paint is being used, and by ordering paint in-house, we will prevent construction defects in advance. Of course, we will also take photos of the used paint and report them.
9. Exterior Wall Painting Color Simulation
9-1 Self Color Simulation
Our simulations can be created from actual photos of your apartment or building!Simulations can also be done on your smartphone or computer. By simulating and then applying a two-tone color or changing the image, we hope to enhance the stylish appearance and contribute to an increase in occupancy rates! Of course, we can also arrange paint samples for actual color confirmation.
* On the official page of Koganei City, no unique landscape plans or landscape regulations were confirmed. In the area covered by the Tokyo Metropolitan Landscape Plan, repairs, renovations, or color changes that alter the appearance of buildings are subject to notification based on the Tokyo Metropolitan Landscape Ordinance, and the same color repainting is also included in the city’s Q&A (normal maintenance activities such as tile repairs are excluded). Notifications must be submitted at least 30 days before the start of construction, and whether it is subject to notification is judged based on the overall scale of the building, not the parts being changed. Additionally, in the area of Koganei City’s district plan, notification is required at least 30 days before starting work if it involves changes in form or design, and confirmation with the city is necessary to determine if exterior wall repainting falls under this category. Having a color simulation screen allows for smooth explanations to the general meeting, neighbors, owners, and residents.
9-2 Confirm the actual color with a trial paint!
It is possible to order samples of the paint being considered and conduct a trial paint on the customer’s exterior wall. By conducting a trial paint, you can confirm the actual color and gloss!
9-3 Exterior Renovation Simulation
Exterior simulations for apartments and condominiums are also possible!
・Exterior wall color simulation (two-tone colors are also possible)
・Simulation for when metal siding is applied
・Simulation using accent materials such as cornices and louvers
・Simulation for roof painting or roof replacement work
With the exterior renovation simulation, you can minimize the risk of failure in image change! We hope that renovating the appearance of apartments and condominiums will help increase occupancy rates.
Cost Estimates for Major Repairs in Koganei City, Tokyo
The cost of major repairs varies greatly depending on the size of the building, deterioration status, scope of work, and materials used. First, please refer to the national average based on public statistics, then to our company’s estimates based on construction performance by scale, and finally to examples of unit prices for each construction.
The national average for condominiums is 750,000 to 1,500,000 yen per unit
According to a survey conducted by the Ministry of Land, Infrastructure, Transport and Tourism, which compiled 818 construction case studies (Fiscal Year 2021), approximately 70% of the costs for large-scale repairs are concentrated in the range of 750,000 to 1,500,000 yen per unit, with the most common price range being 1,000,000 to 1,250,000 yen. Additionally, since this survey does not include consumption tax and common temporary costs, the current total construction costs including tax differ from these figures.
| Construction Cost per Unit | Percentage | Construction Cost per Unit | Percentage |
|---|---|---|---|
| Up to 750,000 yen | 15.1% | 1,250,000 to 1,500,000 yen | 17.4% |
| 750,000 to 1,000,000 yen | 24.7% | 1,500,000 to 2,000,000 yen | 9.1% |
| 1,000,000 to 1,250,000 yen | 27.0% (most common) | Over 2,000,000 yen | 2.8% |
Source: Ministry of Land, Infrastructure, Transport and Tourism “Fiscal Year 2021 Survey on Large-Scale Repair Work for Condominiums” (200 companies, 818 cases) *The amounts do not include consumption tax or common temporary costs. The percentages do not total 100% due to rounding and non-responses.
Breakdown of Construction Costs (What the Money is Spent On)
| Category | Composition Ratio | Main Contents |
|---|---|---|
| Construction-related Work | 60.3% | About half for exterior wall work, about one-third for waterproofing. Substrate repairs, tiles, painting, waterproofing |
| Temporary Work | 22.8% | Scaffolding, mesh sheets, protection, etc. (does not include common temporary costs) |
| Miscellaneous Expenses | 10.3% | Site management fees, general management fees, statutory welfare costs, etc. (9.5%), insurance premiums for large-scale repair defect insurance (0.8%) |
Source: Ministry of Land, Infrastructure, Transport and Tourism “Fiscal Year 2021 Survey on Large-Scale Repair Work for Condominiums” (Second compilation of large-scale repair work. Overall average is construction-related 59.0%, temporary work 22.3%, miscellaneous expenses 9.9%). *The total does not equal 100% because equipment-related work, exterior works, and others are included. This is an average value and not a criterion for judging the appropriateness of individual estimates.
Cost Estimates by Building Size (Scaffolding, Substrate Repair, Exterior Painting, Waterproofing, Sealing)
| Type and Size of Building | Cost Estimate | Estimated Construction Period |
|---|---|---|
| Wooden Apartment (2 stories, 6-10 units) | 2,000,000 – 4,000,000 JPY | 3 – 5 weeks |
| Steel Frame/RC Apartment (3 stories, 10-20 units) | 4,000,000 – 9,000,000 JPY | 1 – 2 months |
| Mixed-Use Building/Small Apartment (4-5 stories) | 5,000,000 – 15,000,000 JPY | 1.5 – 3 months |
| Medium-Sized Apartment (30-50 units) | 20,000,000 – 50,000,000 JPY | 3 – 5 months |
| Large Apartment (over 100 units) | Around 100,000,000 JPY or more | 6 months or more |
* The above estimates are based on Kakeru Koumuten’s construction records and may vary depending on the presence of roofing work, metal work, plumbing, etc. For apartments, please also consider the amount calculated by multiplying the national statistics (750,000 – 1,500,000 JPY per unit) by the number of units as a guideline.
Breakdown of Costs for Temporary Structures, Substrate Repair, Exterior Walls, and Waterproofing
The estimate for large-scale repairs is broadly divided into “temporary structures,” “substrate repair,” “sealing,” “exterior painting,” “waterproofing,” and “miscellaneous expenses.” Before comparing total amounts, please check what each item includes, how much, and at what cost.
| Item | What to Confirm in the Estimate |
|---|---|
| Building Prerequisites | Structure (wooden, steel frame, RC), number of floors, number of units, exterior wall area, waterproof area. Confirm whether the area is based on drawings or actual measurements. |
| Common Temporary Works & Scaffolding | Scaffolding area and unit price, mesh sheets, protection, temporary toilets, etc. According to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for Reiwa 3, temporary works such as scaffolding account for about 20% of construction costs (excluding common temporary costs). |
| Substrate Repair | Cracks, lifting, spalling, etc., quantity and unit price for each repair method. Since this item is not confirmed until scaffolding is set up, confirm whether it is estimated quantity or actual settlement, and the settlement method if the quantity increases or decreases. |
| Sealing | Whether it is a replacement or additional sealing, length to be installed (m), material name. |
| Exterior Wall Painting | Painting area (㎡), paint manufacturer name, product name, grade, number of coats, range of ancillary parts. |
| Waterproofing | Area for each part such as rooftop, balcony, shared corridor, construction method, material name, and whether drain renovation is included. |
| Inspection & Reporting | Inspections for each process, construction photos, whether a completion report and warranty are included. |
| Miscellaneous Expenses | Contents and ratios of site management fees, general management fees, statutory welfare expenses, etc. According to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for Reiwa 3, the average is about 10% of construction costs, but it varies depending on the size and conditions of the building, so there is no uniform standard. |
| Tax Classification | Whether the amount is tax-inclusive or tax-exclusive. Since companies display this differently, always ensure consistency before comparing total amounts. |
Unit Price Examples for Repair Work
| Repair Method | Materials Used | Cost |
|---|---|---|
| Tile Replacement | Existing Similar Tiles | per piece / 2,000 JPY〜4,000 JPY |
| Repair of Floating Tile and Mortar Areas | Epoxy Resin Injection | per square meter / 3,000 JPY〜5,000 JPY （Varies depending on the degree） |
| Tile Joint Mortar Repair | Mortar for Tile Joints | per square meter / 1,000 JPY〜2,000 JPY （Varies depending on the degree） |
| Concrete Spalling Repair | Reinforcement Rust Prevention + Resin Mortar | per location / 1,000 JPY〜2,000 JPY （Varies depending on the degree） |
| Crack Repair | Filler or Polymer Cement | per meter / 100 JPY〜2,500 JPY （Varies depending on the degree） |
| Exterior Wall Painting (3 Coats) | Radical Control Silicone Paint | per square meter / 2,500 JPY〜3,500 JPY |
| Roof Waterproofing with Urethane (Ventilated Buffer Method) | High-Strength Urethane | per square meter / 6,500 JPY〜9,500 JPY |
| Sealant Replacement | Modified Silicone | per meter / 900 JPY〜1,500 JPY |
| Temporary Scaffolding | In-House Owned Scaffolding Materials (Wedge Type) | per square meter / 700 JPY〜1,000 JPY |
*Costs and warranty years vary depending on shape, quantity, substrate condition, and type of materials. For a detailed estimate, please feel free to contact us. Estimates are completely free.
Select Paint and Waterproofing Grades Based on “Years Until Next Repair”
“Good paint does not equal the right choice.” The best way to choose is to align when the next major repair will be with the lifespan of the materials, minimizing waste.
| Grade | Estimated Lifespan | Suitable Cases |
|---|---|---|
| Silicone / Radical Control Type | 10-16 years | Buildings that are cycled every 12-15 years. A good choice balancing cost and performance. The lifespan varies by product, so choose specifications that match the cycle. |
| Fluorine | 16-20 years | Buildings where the next repair is set for 15 years or later, and high-rise or complex-shaped buildings where scaffolding costs are high. |
| Inorganic | 18-22 years | Buildings that want to suppress dirt adhesion. Effective for suppressing moss and algae on the north side or poorly lit areas. |
| Urethane Waterproofing (Rooftop) | 8-15 years | Complex-shaped rooftops, or when wanting to renovate while utilizing the existing waterproof layer. Mid-term inspections and repairs, such as re-coating the top coat, are prerequisites. |
| PVC Sheet Waterproofing | 20-25 years | Rooftops with a large area and simple shape. Short construction time. |
| Asphalt Waterproofing | 15-20 years | Rooftops planned for long cycles. The cost per instance increases. |
* The estimated lifespan is a general guideline and may vary depending on sunlight, location, and substrate condition. Choosing paints with anti-algae and anti-mold properties can improve durability in shaded and humid areas.
Guidelines for Repair Reserve Funds and Options When Insufficient
The Ministry of Land, Infrastructure, Transport and Tourism guidelines provide estimates for repair reserve funds on a monthly basis per exclusive area. Additional charges are necessary if there is a mechanical parking lot.
| Building Size (Less than 20 Floors) | Monthly Estimate (Average) | Range Covering Two-Thirds of Cases | Conversion for 70㎡ |
|---|---|---|---|
| Less than 5,000㎡ Total Floor Area | 335 JPY/㎡ | 235-430 JPY/㎡ | Approximately 16,500-30,100 JPY |
| 5,000-10,000㎡ | 252 JPY/㎡ | 170-320 JPY/㎡ | Approximately 11,900-22,400 JPY |
| 10,000-20,000㎡ | 271 JPY/㎡ | 200-330 JPY/㎡ | Approximately 14,000-23,100 JPY |
| Over 20,000㎡ | 255 JPY/㎡ | 190-325 JPY/㎡ | Approximately 13,300-22,750 JPY |
Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines on Repair Reserve Funds for Condominiums” (Reiwa 6, June revision, PDF) / National average is 13,378 JPY per unit per month (Reiwa 5 Fiscal Year Comprehensive Survey of Condominiums)
In the Reiwa 5 Fiscal Year Comprehensive Survey of Condominiums, 36.6% of management associations reported that “repair reserve funds are insufficient compared to the plan.” There are four main options when funds are insufficient.
| Options | Considerations and Points of Caution |
|---|---|
| ① Adjusting the Construction Schedule | Based on deterioration diagnosis, postpone less urgent work to the next time. However, it is essential to distinguish between work that can be postponed and work that cannot, as delaying waterproofing and tile fall prevention measures can ultimately be more costly. |
| ② Reviewing the Scope and Specifications of Work | Revising paint grades, changing from full renovation to partial renovation, etc. Please consider this separately from “apparent reductions” that skip processes. |
| ③ Utilizing Subsidies and Tax Systems | Subsidies for energy-saving renovations from the national and Tokyo Metropolitan governments, fixed asset tax reductions, and management plan certifications in Koganei City, etc. (described later). The fixed asset tax reduction is a system that lowers the tax amount for each unit owner, and does not directly increase the repair funds of the management association. |
| ④ Increasing Reserve Funds, Borrowing, and One-Time Payments | In addition to considering increasing the repair reserve fund at the general meeting, the Japan Housing Finance Agency’s condominium common area renovation loan requires no collateral. Interest rates can be lowered by obtaining management plan certification. |
Subsidies, Tax Systems, and Loans to Check for Large-Scale Renovations in Koganei City, Tokyo
Based on the official page of Koganei City, there does not appear to be a municipal system that subsidizes the construction costs of large-scale renovations for condominiums. The city provides information on fixed asset tax reductions, management plan certifications, management status reports, and plans to promote proper condominium management, among others. The main types available are broadly divided into five categories. The eligibility and application status of these systems may change during the fiscal year, so please be sure to confirm with our company or each contact point before contracting or starting construction. (As of October 15, 2026)
| Type | Details |
|---|---|
| ① Support from Koganei City | Promotion plan for appropriate management of condominiums, management status reporting system, consultation desk regarding the management of condominiums, publication of actual survey reports. The city’s seismic assistance is targeted at wooden houses and similar structures. The contact point is the Urban Development Promotion Division, Housing Section. |
| ② Tax Incentives | Reduction of fixed property tax under the condominium longevity promotion tax system (in Koganei City, fixed property tax is a city tax, and the reduction rate is one-third. You must report to the Property Tax Division within three months after the completion of the work). |
| ③ Management Plan Certification System | A certification system that serves as an entry point for tax incentives and loan interest rate reductions. Condominiums in Koganei City can apply through the Koganei City (Urban Development Promotion Division, Housing Section), and online applications via the Condominium Management Center are also available. |
| ④ Purpose-specific Construction Subsidies | Energy-saving (windows, insulation, etc.), seismic measures, etc. The Koganei City residential new energy equipment promotion subsidy is for individuals, and applications for the fiscal year 2026 have closed. Please check in conjunction with national and Tokyo metropolitan projects. |
| ⑤ Loans and Interest Subsidies | Loan for renovation of common areas of condominiums from the Japan Housing Finance Agency, interest subsidies from Tokyo Metropolitan Government (subsidy for condominium improvement work). |
We have organized the information that Koganei City provides for condominium management associations based on what we could confirm on the city’s official page. None of these are systems that directly cover the costs of large-scale repair work.
| Mansion Management Improvement Promotion Plan | The city has formulated the Koganei City Mansion Management Improvement Promotion Plan with the aim of preventing mismanagement, promoting proper management, and facilitating the smooth regeneration of aging mansions (the page was last updated on April 12, 2022). The plan sets a target of 79.2% for the reporting rate of management status for mansions that require notification (as of January 2022) and 68.1% for the proportion of management associations that have established repair reserve funds based on long-term repair plans of 30 years or more (as of January 2021), with the latter aiming to exceed 80% by the end of fiscal year 2030. |
|---|---|
| Management Status Reporting System | This applies to mansions with six or more units built before 1983, and reporting began on April 1, 2020. The point of contact for reporting to the city is the Urban Development Promotion Division, Housing Section (042-387-9861). |
| Consultation Desk & Actual Condition Survey | The city’s housing and support page provides information on consultation desks regarding the management of condominiums and reports on actual condition surveys of condominiums. I could not confirm any information regarding advisor dispatch or subsidy systems for management associations. |
| Support for Earthquake Resistance | The subsidies provided by the city include seismic diagnosis and seismic renovation for wooden houses, removal of block walls, and earthquake resistance for buildings along designated emergency transport roads. The city’s earthquake renovation promotion plan page does not mention subsidies for the earthquake renovation of condominiums. Tokyo Metropolitan Government offers the “Emergency Measures Subsidy for Piloti Floors, etc. to Protect Lives,” targeting condominiums with piloti floors that are at high risk of collapse under old seismic standards (Tokyo Metropolitan Government Condominium Division 03-5320-4944. Please confirm with the metropolitan government whether you are eligible). |
*Based on the information available on Koganei City’s official page, there appears to be no city subsidies for asbestos investigation or removal work. The city has a page providing information regarding asbestos. For notifications related to dust prevention, please confirm with the city or Tokyo Metropolitan Government’s desk during the planning stage of the construction. Since the reception status may change, please check the latest handling at the desk before applying.
- Koganei City: Housing Support (Official)
- Koganei City: Condominium Management Improvement Plan (Official)
- Koganei City: Condominium Management Status Reporting System (Official)
- Koganei City: Report on the Actual Conditions of Condominiums (Official)
- Koganei City: Earthquake Resistance Renovation Promotion Plan (Official)
- Koganei City: About Asbestos (Official)
② Condominium Long-term Life Promotion Tax System (Reduction of Fixed Asset Tax)
If large-scale repairs that contribute to the long-term life of certain condominiums meeting specific requirements (conducting exterior painting, floor waterproofing, and roof waterproofing as a single project) are carried out, the fixed asset tax amount for the building in the following fiscal year will be reduced (up to the equivalent of 100㎡ per unit; urban planning tax is not included). The reduction rate is determined by local ordinances. In Koganei City, the fixed asset tax is a city tax, and according to Koganei City’s information, the fixed asset tax amount for the house in the fiscal year following the completion of the work will be reduced by one-third (in the 23 wards of Tokyo, the fixed asset tax is a metropolitan tax, and the reduction rate is one-half).
| Main Requirements of the National System | For buildings over 20 years old and with a total of 10 or more units, the floor area of the residential exclusive parts must be more than half of the total exclusive area. The building must have undergone exterior painting, floor waterproofing, and roof waterproofing at least once each in the past. It must be a condominium that has received management plan certification and has raised the amount of the repair reserve fund (average amount for the entire planning period) from below the certification standard to above the standard after September 1, 2021, or a management association that has received administrative advice and guidance based on the Condominium Management Improvement Act, resulting in a long-term repair plan that meets national standards. |
|---|---|
| Implementation Deadline of the National System | From April 1, 2023, to March 31, 2027 (the same period is indicated in the information from Koganei City). |
| Treatment by Koganei City | The reduction rate is one-third, applicable to the fixed asset tax for buildings. The reduction applies to the following fiscal year after the completion of the work. The declaration deadline is within three months after the completion of the work, and the declaration should be made to the Koganei City Hall, 3rd floor of the Second Building, Property Tax Division, Building Section (042-387-9821). The management association can also declare on behalf of all unit owners. The last update date on the city’s page is April 17, 2025. |
| Main Submission Documents | On the city’s page, the documents are divided into two cases: condominiums that have received management plan certification and those that have received city advice and guidance. In both cases, a reduction declaration form (not required if the management association is declaring collectively), a large-scale repair certificate (issued by an architect or housing defect liability insurance corporation), and a past work certificate (issued by the management company or architect) are required. For certified condominiums, a repair reserve fund increase certificate and a copy of the management plan certification notification issued by the city (City Development Promotion Division) are required. For the advice and guidance condominiums, a certificate of implementation of the advice and guidance issued by the city is required. |
| Points to Note | Obtaining management plan certification and reviewing the long-term repair plan takes time, so it is recommended to prepare at least one year before the construction. It is stated that the fixed asset tax reductions for seismic, barrier-free, and energy-saving renovations cannot be used in the same fiscal year. The treatment after April 2027 has not been confirmed on the official page. |
- Koganei City: Reduction of fixed asset tax due to large-scale repair work for extending the lifespan of condominiums (Official)
- Ministry of Land, Infrastructure, Transport and Tourism: Tax system for promoting the longevity of condominiums (Official)
- Ministry of Land, Infrastructure, Transport and Tourism: Fixed asset tax will be reduced if large-scale repairs are made to your condominium (PDF)
- Ministry of Land, Infrastructure, Transport and Tourism: Are you regularly repairing your condominium? (PDF)
③ Management Plan Certification System (Entrance to Tax and Interest Rate Benefits)
Receiving certification leads to fulfilling one of the requirements for interest rate benefits from the Housing Finance Agency’s loans and bonds, as well as the longevity promotion tax system (certification alone does not guarantee a tax reduction). For condominiums in Koganei City, Koganei City serves as the certification window. The city’s page does not list any additional criteria unique to the city, and the certification standards are indicated by referring to the Ministry of Land, Infrastructure, Transport and Tourism’s guidelines. The main criteria include holding meetings at least once a year, maintaining management regulations, separating accounting for management fees and repair reserves, and “having a long-term repair plan that includes large-scale repair work at least twice and is created or reviewed within 7 years, with a planning period of over 30 years”.
| Application Process (Example) | ① Request certification application from the Public Interest Incorporated Foundation Condominium Management Center and receive a preliminary confirmation by a condominium management specialist → ② Receive a preliminary confirmation compliance notification (compliance certificate) → ③ Apply for certification to Koganei City → ④ After examination, certification is granted, in that order. You can also apply directly to the city (paper). |
|---|---|
| Fees | If applying directly to the city (paper), the fee is 27,200 yen, and if there are multiple long-term repair plans, an additional 15,700 yen is added for each subsequent plan. If applying via the Condominium Management Center (online), the city’s fee is 3,900 yen (1,700 yen added for each additional case), and a separate fee for the preliminary certification application to the Condominium Management Center is required. |
| Number of Certifications | The city’s page does not provide information on the number of certifications. |
| Consultation Desk | Koganei City Urban Development Department City Planning Promotion Section Housing Division 042-387-9861 (Page update date: Reiwa 5, June 13) |
④ National Energy-Saving Support | Housing Energy-Saving 2026 Campaign
Changes for 2026The “Child-Rearing Green Housing Support Project” for 2025 has been abolished and reorganized into the successor “Mirai Eco Housing 2026 Project.” Additionally, the “Long-Term Excellent Housing Renovation Promotion Project” will end in Reiwa 7, and will not be implemented in Reiwa 8. Please be careful not to base your financial plans on outdated information.
Mirai Eco Housing 2026 Project
| Eligible | Renovations of existing homes built before December 31, 2016, regardless of whether they are single-family or multi-family dwellings. Management associations and management association corporations can also become joint contractors (i.e., can be used for common area renovations). Rental housing is also eligible. |
|---|---|
| Required Work | Combination of insulation renovations for openings, structural (floor, wall, ceiling) insulation renovations, and installation of eco-friendly housing equipment is mandatory. |
| Subsidy Limit | Depending on the age of the building and the energy-saving performance achieved, 400,000 to 1,000,000 yen per unit (1,000,000 yen if reaching the mandatory standards for homes built before 1991). |
| Period | Projects that have started construction after signing a construction contract between November 28, 2025, and no later than December 31, 2026, are eligible. Grant applications are generally made by the registered contractor (construction contractor) after the completion of the work (the client cannot apply themselves). Reservations for grant applications must be made by November 16, 2026, at the latest, and grant applications must be submitted by December 31, 2026, at the latest (will end as soon as the budget limit is reached). |
Advanced Window Renovation 2026 Project
| Target | Installation of interior windows, replacement of exterior windows, glass replacement, etc., for existing homes (detached and multi-family) to upgrade to high-performance windows. For multi-family housing, subsidy unit prices are set separately for “low-rise” and “mid-to-high-rise” buildings. |
|---|---|
| Bulk Application for Multi-Family Housing | In multi-family housing, there is a method called “bulk application” where all units can be applied for together. The application process is carried out by registered contractors (window renovation contractors), and the management association cannot apply on its own, but it is a system that works well with window and entrance door renovations that coincide with large-scale repairs. |
| Subsidy Limit | For residential properties, 1 million yen per unit (changed from 2 million yen in fiscal year 2025). For non-residential properties over 240 square meters, the limit is 10 million yen per building. |
| Period | Construction that starts on or after November 28, 2025, and by no later than December 31, 2026, is eligible. The grant application must be made after the completion and handover of the construction, with reservations made by no later than November 16, 2026, and grant applications submitted by no later than December 31, 2026 (ends once the budget limit is reached). |
⑤ Subsidies and Grants in Tokyo and Koganei City
| Tokyo Energy Conservation Renovation Promotion Project for Existing Homes (Fiscal Year 2026) | The renovation of high-insulation windows, doors, insulation materials, and bathtubs is eligible, and the target group includes management associations of condominium buildings. For management associations with 50 or more renovated units, the subsidy amount will be 120% of the total unit price. The maximum subsidy for windows and doors is 2 million yen per unit, and for insulation materials, it is up to 1 million yen per unit, covering one-third of the expenses. Pre-registration started on May 29, 2026. Contracts and construction will take place after the pre-registration acceptance. It was not confirmed on the official page whether construction of common areas is eligible. Please check the official page and the contact number (03-6737-5300) for conditions regarding registered businesses and budget status. |
|---|---|
| Koganei City Residential New Energy Equipment Promotion Subsidy (Fiscal Year 2026) | Eligible individuals are those living in the city, with no delinquency in city taxes, who purchase and own the equipment themselves, and there is no mention of targeting condominium buildings or management associations. The “insulated windows” subsidy covers one-fifth of the installation costs (up to 100,000 yen), and all windows in the living space must be renovated with registered products. “Heat-reflective coating” applies to the entire roof or rooftop, and exterior walls are not eligible. The budget for fiscal year 2026 has reached its limit, and applications have closed. (The page was last updated on September 16, 2026. There is no mention of the closing date.) Future handling from fiscal year 2027 onwards will need to be confirmed when the city posts information on its page. |
| Koganei City Asbestos Measures | The city’s homepage has a page with information regarding asbestos. It was not confirmed whether the city provides subsidies for surveys or removal work. For notifications regarding dust prevention, please check with the city or Tokyo Metropolitan Government at the planning stage. |
| Tokyo Emergency Measures Subsidy for Piloti Floors to Protect Lives | This applies to condominiums built under old seismic standards that have piloti floors with a high risk of collapse, and part of the reinforcement costs will be subsidized. The contact point is the Tokyo Metropolitan Government Housing Policy Headquarters, Private Housing Department, Condominium Division, Seismic Reinforcement Section (03-5320-4944). Please check the official page for detailed requirements and application status. |
| Tokyo Rental Housing Insulation and Renewable Energy Concentration Promotion Project (Fiscal Year 2026) | This targets owners of existing rental housing under ordinary rental contracts, and construction must be carried out by registered businesses of Cool Net Tokyo. Pre-registration is from May 29, 2026, to March 31, 2027, and will end once the total application amount reaches the limit. The subsidy rate is two-thirds, with a maximum of 300,000 yen per unit for high-insulation windows and 600,000 yen per unit for insulation material renovations. No mention was found regarding management associations of condominium buildings being eligible, and this project is aimed at owners of rental apartments and rental condominiums. |
| Tokyo Special Nursing Home Renovation Cost Subsidy (Fiscal Year 2026) | This is a Tokyo Metropolitan Government project supporting renovations of elderly facilities. It cannot be used for large-scale repairs of condominiums or apartments and is aimed at those who own and operate facilities such as special nursing homes. Please check the Tokyo Metropolitan Government’s explanatory video and official page for eligibility and conditions. |
* The Tokyo rental housing project is aimed at owners of rental apartments and rental condominiums, and no mention was found regarding management associations of condominium buildings being eligible. The application status may change, so please be sure to check the official page before applying.
- Koganei City: Subsidy for the Promotion of New Energy Equipment for Residential Use (Reiwa 8) (Official)
- Tokyo: Energy Conservation Renovation Promotion Project for Existing Homes (Official)
- Tokyo: Subsidy for Emergency Measures for Piloti Floors to Protect Lives (Official)
- Tokyo: Promotion Project for Insulation and Renewable Energy Concentration in Rental Housing (Official)
- Tokyo: Announcement of the Start of the Insulation and Renewable Energy Concentration Promotion Project for Rental Housing (Official)
- Tokyo: Explanation Video on Subsidies for Renovation Costs of Special Nursing Homes
⑥ Financing System (Housing Finance Agency Mansion Sumairu Loan)
When a management association borrows funds for large-scale repairs, they can utilize the Housing Finance Agency’s “Mansion Common Area Renovation Loan (Mansion Sumairu Loan).”
| Eligible Work | Large-scale repairs, seismic retrofitting, flood prevention measures, energy conservation measures, balcony repairs, safety measures for elevators and parking lots, asbestos measures, costs for diagnosis and design by specialists |
|---|---|
| Collateral | No collateral required (Joint guarantee by the Mansion Management Center, etc.) |
| Repayment Period | Generally 1 to 10 years; for specific works, 1 to 20 years; if seismic, flood, and energy conservation works are carried out after obtaining management plan certification, up to 35 years |
| Interest Rate Reduction | ① Holding of Sumairu Bonds ② Obtaining Management Plan Certification ③ Implementation of seismic, flood, and energy conservation works, each reducing by 0.2% per year (up to 0.6% per year) |
| Main Requirements | Improvement of management regulations, resolution at the general meeting, repair reserve fund delinquency rate generally within 10%. Applications accepted year-round |
Source: Housing Finance Agency “Mansion Sumairu Loan” (Official)
Tokyo Mansion Improvement Work Subsidy (Interest Subsidy)
| Content | This is a system where the Tokyo Metropolitan Government subsidizes the interest of the “Condominium Common Area Renovation Loan” provided by the Japan Housing Finance Agency. The subsidy covers the difference between the interest rate of the agency and 1% lower (if the interest rate is below 1%, it effectively becomes 0%), and the subsidy period is up to 20 years, which is the repayment period of the loan. |
|---|---|
| Eligibility | This applies to the management associations of fire-resistant condominiums in Tokyo that utilize the agency’s loans and debt guarantees from the Condominium Management Center, etc. Repairs and renovations of common areas are eligible (installation work for solar power generation equipment may also be eligible for the loan. Please check with the Japan Housing Finance Agency for conditions). Condominiums built before the earthquake resistance standards (before May 31, 1981) must undergo an earthquake resistance diagnosis, and those requiring management status notifications must have completed their notifications and updates. |
| Limit | The limit is the smallest amount among the loan reservation amount, the construction cost eligible for the loan, the amount excluding subsidies from the construction cost, and 2 million yen per unit (6 million yen if it involves earthquake reinforcement) multiplied by the number of units. |
| Application for Reiwa Year 8 | The application is in two phases, with the first phase (May 13 – September 30) having ended. The second phase will be accepted from October 1, 2026, to February 19, 2027. Each phase has 2,500 units available on a first-come, first-served basis. After loan approval, applications and grant decisions must be received before the money lending contract. Contact: Tokyo Metropolitan Government Housing Policy Headquarters, Private Housing Department, Condominium Division 03-5320-7532 |
Cases Where Fire Insurance Can Be Used and Cases Where It Should Not Be Used
Damage caused by “accidental incidents” such as the scattering of rooftop waterproof sheets, caps, and fences due to typhoons or strong winds, hail damage, and lightning strikes may be covered by fire insurance. It is important to separate and record damage caused by accidents from normal wear and tear during deterioration diagnosis.
On the other hand, normal wear and tear itself is not covered. There have been many troubles nationwide with businesses soliciting that “repairs can be made without out-of-pocket expenses using insurance money,” and the National Consumer Affairs Center has repeatedly issued warnings. False claims can lead to insurance fraud charges. Please confirm the eligibility of claims directly with your management association or property owner to the insurance company or agent. Kakeru Koumuten Co., Ltd. does not provide any such guidance.
Building Conditions and Repair Points in Koganei City, Tokyo
Koganei City is located in the southwestern part of the Musashino Plateau, covering an area of 11.30 km². The city has a maximum elevation difference of about 35 meters between the northern Musashino Terrace and the southern Tachikawa Terrace, divided by the Kokubunji Cliff Line (commonly known as “Hake”) that runs east-west through the center of the city. Approximately 95% of the land use is residential, with about 65% designated as first-class low-rise residential areas (as of September 1, 2014). According to a survey by Tokyo Metropolitan Government, there are 202 condominium buildings in the city, of which 34 are of old seismic design (announced in March 2013). The numbers below are only those confirmed from official documents.
（As of October 1, Reiwa 6）
（As of October 1, Reiwa 6）
（City’s Basic Environmental Plan）
（Tokyo Metropolitan Government survey, announced March 2013）
（Same as above, out of the 202 buildings）
Source: Koganei City “Households and Population (As of October 1, Reiwa 6)” (PDF)／Koganei City “Basic Environmental Plan Chapter 2” (PDF)／Koganei City “Condominium Management Promotion Plan” (PDF) ※The population and household numbers are the latest monthly data confirmed on the city’s page. The number of condominium buildings is as stated in the city’s plan based on the results of the Tokyo Metropolitan Government’s condominium survey (announced March 2013).
Koganei City’s condominiums are believed to have a significant number built between 26 to 45 years ago
According to the city’s actual survey (conducted from August to November 2010, targeting 179 condominium buildings that are non-wooden and completed by March 2010, with 98 valid responses), the number of buildings by year of completion shows that the years from Heisei 3 to 12 account for 63 buildings (35.2%), the highest, followed by 41 buildings (22.9%) from Showa 56 to Heisei 2, 41 buildings (22.9%) from Heisei 13 to 22, and 34 buildings (19.0%) from before Showa 55. Sixteen years have passed since the survey, and the ages of the buildings have increased by 16 years each. The table below replaces the completion year categories from the survey with an estimate of the building ages as of 2026.
| Year of Completion (Survey Classification for Heisei 22) | Number of Cases (179 cases) | Estimated Age (as of 2026) | Major Repairs in Next Renovation |
|---|---|---|---|
| Before Showa 55 5 cases from Showa 36-45, 29 cases from Showa 46-55 |
34 cases (19.0%) | Over 46 years old | 3rd to 4th repairs. Replacement of water supply and drainage pipes, replacement of iron parts and handrails, seismic diagnosis will be the main issues |
| Showa 56 to Heisei 2 | 41 cases (22.9%) | 36 to 45 years old | Around the 3rd repair. Full renovation of waterproofing layer, equipment updates, renovation of sashes and entrance doors are likely to be the focus |
| Heisei 3 to 12 | 63 cases (35.2%) | 26 to 35 years old | 2nd to 3rd repairs. Replacement of waterproofing layer and sealing, equipment updates are the main focus, and decisions will be made by comparing the previous specifications and the degree of deterioration |
| Heisei 13 to 22 | 41 cases (22.9%) | 16 to 25 years old | 1st to 2nd repairs. Exterior wall painting, sealing, rooftop waterproofing are the main tasks |
Source: Koganei City “Koganei City Condominium Actual Condition Survey Report (March 2011)” (PDF) *The estimated age is calculated from the cutoff year and does not indicate the degree of deterioration. Buildings completed after April 2010 are not included in this survey. The classification “before Showa 55” is based on the year of completion and slightly differs from the old seismic standards (before May 31, 1981).
Four Factors Influencing Buildings and Construction in Koganei City
Based on public documents, we have organized four characteristics that are linked to large-scale repairs. Koganei City is characterized by the elevation differences of the Kokubunji Cliff Line and a spread of low-rise residential areas, and it is believed that there are many condominiums aged 26 to 45 years. Therefore, diagnosis according to age, as well as confirmation of scaffolding plans and notifications, is essential.
① Climate | Temperature Differences, Heat Waves, Heavy Rain
According to the Japan Meteorological Agency’s observations in Tokyo (not based on data from Koganei City), the highest annual temperatures from 2021 to 2025 (the highest daily temperature of that year) ranged from 36.8 to 38.5℃, while the lowest annual temperatures (the lowest daily temperature of that year) ranged from -3.5 to -1.0℃ (the highest in 2025 was 38.5℃ in August). The annual precipitation varied significantly, with the highest in 2021 at 2,052.5mm and the lowest in 2025 at 1,152.5mm. Due to high summer temperatures and cold winters, the exterior walls, sealing, and waterproof layers undergo repeated expansion and contraction every year.We recommend inspecting the waterproof layers, sealing, and drains before any issues arise.
② Topography and Flooding | Kokubunji Cliff Line (Hake), Tamagawa Josui, Nogawa
According to the city’s environmental basic plan, there is a maximum elevation difference of about 35m between the northern flat area (Musashino Plateau) and the southern flat area (Tachikawa Plateau), divided by the Kokubunji Cliff Line (commonly known as Hake), which runs east-west through the center of the city. Above the cliff line, the Tamagawa Josui and Sendagawa rivers flow, while below the cliff line, the Nogawa river flows east-west. The city’s flood hazard map (flood prediction area map) is based on the maximum rainfall anticipated by Tokyo (total rainfall of 690mm over 24 hours, maximum of 153mm in one hour) and covers areas such as the Nogawa river basin. The city’s disaster prevention map was fully revised in March of Reiwa 7. Please check the city’s disaster prevention map and on-site conditions to determine which assumptions apply to your property and whether it is located in an area with elevation differences near the cliff line.
③ Types of Buildings | Low-rise Residential Areas and Condominiums
The land use zoning is approximately 95% residential, with about 65% designated as first-class low-rise residential areas (as of September 1, 2014). According to the taxation data from 2013, about 85% of the taxable land was residential, and about 11% was farmland. According to the city’s housing master plan, the 2018 housing and land statistical survey indicated that 24.9% of condominiums were owner-occupied and built before 1980, which is higher than single-family homes. A survey by Tokyo found that there are 202 condominium buildings in the city, of which 34 are of the old seismic design (announced in March 2013). Condominiums built within low-rise residential areas are influenced by the width of the front road and the distance to neighboring properties in terms of scaffolding plans, so it is important to confirm the surrounding conditions of the site, in addition to the year of construction and the details of the previous work with each management association when planning.
④ City Rules | District Planning, Tokyo Landscape Ordinance
On the official page of Koganei City, there was no confirmation of the city’s unique landscape plans or landscape ordinances. In areas designated by the Tokyo Landscape Plan, notifications based on the Tokyo Landscape Ordinance may be required depending on the overall scale of the building (Urban Development Bureau, Green Space and Landscape Division 03-5388-3265. The scale varies by area). According to the city’s Q&A, repainting in the same color is also subject to notification (normal maintenance activities such as tile repairs are excluded). In areas designated by the city’s district planning, if you plan to construct a building or make changes to its form or design, you must notify the mayor at least 30 days before starting construction, and for construction requiring building confirmation, this must be done before the confirmation application (City Planning Promotion Division, City Planning Section 042-387-9862). It is necessary to confirm at the counter whether exterior wall repainting is applicable, as this is not clearly stated on the city’s page. The number of district planning areas, guidelines for greening, and the number of building agreements could not be confirmed from the city’s page. Please check with the counter for each property.
Source: Japan Meteorological Agency “Past Weather Data (Tokyo)”／Koganei City “Basic Environmental Plan Chapter 2 Current Status and Issues” (PDF)／Koganei City “Housing Master Plan (Draft)” (PDF)／Koganei City “Koganei City Disaster Prevention Map”／Koganei City “Notification of District Planning”／Tokyo Metropolitan Government “Landscape Formation by Notification System”／Tokyo Metropolitan Government “Landscape Ordinance Q&A” (PDF)
Key Issues to Consider When Proceeding with Construction in Koganei City
| Issue | Current Situation in Koganei City and Kakeru Koumuten’s Response |
|---|---|
| Road Occupation and Scaffold Extension | If scaffolding or temporary enclosures extend onto the road, a road occupation permit is required. In Koganei City, the Road Management Division (042-387-9849) is the point of contact, and applications for occupation permits and consultation documents (Forms No. 1 to No. 3) must be submitted in duplicate. As a general rule, applications sent by mail are not accepted. If scaffolding or temporary enclosures extend onto the sidewalk, it is essential to obtain the opinion of Koganei Police Station in the consultation document if it is deemed necessary for the roadway. According to the city’s permit criteria, the extension on the sidewalk must be less than 1m from the road edge and less than one-third of the effective width, ensuring a passage width of at least 1.5m excluding the occupied items. For the roadway, the extension must be less than 1m from the road edge and less than one-eighth of the road width, with height conditions for cantilever scaffolding. Prior consultation is advised, and the standard processing period and occupation fee amount are not listed on the city’s page. After obtaining permission, a construction start notification and completion notification (with a photo record attached) are required. We will confirm the width of the front road and the delivery route on-site, incorporating the need for occupation and the schedule for procedures into the project timeline. |
| District Planning and Landscape | In areas subject to district planning, notification is required at least 30 days before starting construction if there are changes in form or design. It is not clearly stated on the city’s page whether repainting the exterior walls falls under this requirement, so we will confirm at the point of contact. There may also be a need for notification under the Tokyo Metropolitan Landscape Ordinance. We will verify whether it is applicable before starting construction and incorporate it into the project if necessary. |
| Old Seismic Buildings and Seismic Diagnosis | According to a survey by Tokyo Metropolitan Government, 34 out of 202 condominium buildings in the city are classified as old seismic (announced in March 2013). The city’s seismic assistance is targeted at wooden houses, and there is no mention of city assistance for seismic diagnosis or renovation of condominiums on the seismic renovation promotion plan page. During the planning stage of large-scale repairs, we will organize the necessity of seismic diagnosis and propose a combination of works that can be done while scaffolding is in place. |
| Window Insulation and Subsidies | The city’s subsidy for promoting the spread of new energy equipment for residential use is for individuals, and applications for the fiscal year 2026 have already closed. If window renovations are included in large-scale repairs, we will check whether the national advanced window renovation 2026 or Tokyo’s projects can be utilized, confirming each system before the contract and organizing the schedule based on the general meeting timeline. |
| Height Differences Along the Cliff Line and Drainage | There is a maximum height difference of about 35m along the Kokubunji Cliff Line, and the flood hazard map indicates areas expected to be inundated, such as Nogawa. The height differences on the site, the presence or absence of retaining walls, blockages in roof drains, gutters, and drainage pipes, and how water enters low floors or basements will be organized together during the diagnosis. |
| Reserve Funds and Long-Term Repair Plans | According to a survey conducted by the city in 2010, 27.2% of management associations reported that their repair reserve funds were “insufficient,” and 24.5% stated that their long-term repair plans were “created but need revision.” The city’s plan requires management status reports for condominiums built before 1983 with six or more units. We will organize the review of the long-term repair plan and prioritize the scope of this construction based on the results of the diagnosis. |
Source: Koganei City “Regarding Road Occupancy Permit Applications”／Koganei City “Permit Standards for Scaffolding Occupancy” (PDF)／Koganei City “District Planning Notification”／Koganei City “Report on the Actual Conditions of Condominiums” (PDF)／Koganei City “Regarding the Condominium Management Status Notification System”／Koganei City “Subsidy for the Promotion of Residential New Energy Equipment”／Tokyo Metropolitan Government “Landscape Ordinance Q&A” (PDF)
* We accept consultations throughout Koganei City.
Deterioration Symptoms and Timing Requiring Major Repairs
Generally, major repairs are estimated to occur in a 12 to 15-year cycle. According to the Ministry of Land, Infrastructure, Transport and Tourism’s actual condition survey, the actual repair cycle is most commonly 13 years, with about 70% falling within the 12 to 15-year range, and the cycle tends to shorten with each occurrence. However, the actual determination should be based on the deterioration condition rather than the number of years, so if you observe symptoms like those listed below, an early on-site survey is recommended.
| Location | Dangerous Signs of Deterioration if Left Untreated | Main Countermeasures |
|---|---|---|
| Exterior Wall (Painted Surface) | Chalking (white powder on hands), fading, cracks wider than 0.3mm, paint film blistering or peeling | Substrate repair + exterior wall painting |
| Exterior Wall (Tile Surface) | Tile lifting or falling off, joint chipping, efflorescence, hollow sound when tapped | Injection for lifting, replacement, clear waterproofing |
| Sealing | Cracks in joints, shrinkage, peeling, hardening | Re-sealing |
| Roof and Balcony | Blistering or breaking of waterproof layer, puddles, clogged drains, rain leaks to lower floors | Urethane waterproofing, sheet waterproofing, drain renovation |
| Metal Parts and Steel Stairs | Rust, paint film peeling, corrosion of treads | Grinding + rust prevention + painting, component replacement |
| Roof | Lifting of ridge cap, cracking or warping of slate, moss, shifting of tiles | Roof painting, overlay method, re-roofing |
| Concrete | Spalling (exposed rebar with rust stains), water leakage from cracks | Spalling repair + resin mortar filling |
| Common Corridor and Stair Floor | Lifting or peeling of long sheet, opening at edges, exposure of substrate | Replacement of long sheet + substrate waterproofing |
Estimated Repair Cycles by Location (Ministry of Land, Infrastructure, Transport and Tourism Guidelines)
| Location/Work | Estimated Cycle | Location/Work | Estimated Cycle |
|---|---|---|---|
| Exterior Wall Painting (Repainting) | 12-15 years | Re-sealing | 12-15 years |
| Exterior Wall Painting (Existing Removal + Painting) | 24-30 years | Metal Parts Painting | 5-7 years |
| Roof Waterproofing (Repair) | 12-15 years | Water Supply Pipe (Rehabilitation/Replacement) | 19-23 years / 30-40 years |
| Roof Waterproofing (Removal + New Installation) | 24-30 years | Drain Pipe (Rehabilitation/Replacement) | 19-23 years / 30-40 years |
*The above are reference examples from the guidelines and are not uniform construction deadlines. Actual cycles will be set according to the building’s specifications, location conditions, and deterioration status.
Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines for Creating Long-Term Repair Plans” (Revised June 2024, PDF) / Ministry of Land, Infrastructure, Transport and Tourism “Fiscal Year 2021 Survey on Large-Scale Repair Work for Condominiums”
Examples of Large-Scale Renovation Work
This is an example of exterior renovation work on a mixed-use building undertaken by Kakeru Koumuten. The building had leaks occurring in several places, and we combined clear waterproofing for the tile exterior wall with rooftop waterproofing for the renovation.
Exterior Renovation Work for a Mixed-Use Building (Tile Wall Waterproofing + Roof Waterproofing)
| Work Details | Partial tile replacement for damaged tiles / Painting of ancillary parts (pipes, drip edges) / Roof waterproofing work (urethane waterproofing) / Wall tile waterproofing (Seven S) / Sealing work around windows / Repair of wall tile mortar joints / Removal of ivy |
|---|---|
| New Materials Used | Wall tiles: Kunishiro Tiles / Ancillary part painting: Radical silicone paint / Roof waterproofing: High-strength urethane (Sarasene A) / Wall tile waterproofing: Seven S |
| Price Range | 4,000,000 to 4,100,000 yen |
| Construction Period | 45 days |
| Location | Not disclosed |
| Background to the Work | Due to leaks occurring from several areas such as the exterior walls and roof, we proposed waterproofing for the entire exterior wall. Seven S is a clear waterproofing material for tile walls, and while it is somewhat expensive, it offers high waterproofing performance, making it recommended for cases where leaks are occurring from multiple spots on the exterior wall. |
Customer Feedback
Flow from On-Site Investigation to Completion of Work
From the initial inquiry to the completion of the work and aftercare, a single representative will consistently handle your case. For management associations, a resolution at the general meeting is required, so starting the process 1 to 1.5 years before the desired construction start date allows for a smoother progression.
- Inquiry (Free) Please contact us via phone, form, or LINE. If you have estimates from other companies, just presenting those is fine.
- On-site Investigation & Building Diagnosis (Free) We will conduct a survey of the exterior walls, check for cracks, sealing, and waterproof layers, and if necessary, investigate the rooftop, high places, and leak areas using drones or thermal imaging. For properties in Koganei City, we will also check the site conditions, trees, road width, necessity for road occupation, distance from neighboring buildings, elevation differences near cliff lines, expected flooding from rivers, and access routes and parking.
- Submission of Investigation Report & Estimate We will provide a deterioration diagnosis report with photos and an estimate detailing quantities, methods, and materials for each work item. Multiple plans can also be proposed.
- Plan Decision & Contract Confirm colors through color simulations, paint samples, and trial painting. For management associations, we will assist in preparing materials for the general meeting. If the Tokyo Metropolitan Landscape Ordinance or Koganei City’s district plan applies, we will also explain the color considerations.
- Notification to Residents & Neighbors We will distribute construction notifications, visit neighbors for greetings, and set up a bulletin board at the entrance (with a schedule and laundry information). If temporary relocation of parking is necessary, adjustments will be made at this stage.
- Installation of Temporary Scaffolding & Various Works Our own scaffolding team will set up the scaffolding, followed by high-pressure washing → substrate repair → sealing → exterior wall painting & tile repair → waterproofing → ironwork & ancillary work in that order. A supervisor will inspect each stage and take construction photos.
- Completion Inspection, Scaffolding Dismantling & Handover We will confirm the finish in the presence of the customer and provide construction photos, a report on the paint used, and a warranty.
- Aftercare We will send out annual DM notifications, and inspections can be conducted every year. Simple repairs such as partial sealing are provided free of charge.
Resident Interaction, Approval for Additional Work, Inspection Reports
Equally important as the construction itself is “when, what, and with what materials we report”. At Kakeru Koumuten, we provide materials and reports in the following four situations.
| Situation | What We Provide or Do |
|---|---|
| Before Construction Building Diagnosis |
We will provide a deterioration diagnosis report with photos. This document summarizes the deteriorated areas and the rationale for the proposed scope of work. |
| Before Construction to During Construction Notification to Residents & Neighbors |
We will distribute construction notifications, visit neighbors for greetings, and provide information on the schedule and laundry through the entrance bulletin board. |
| During Construction Approval for Additional Work |
Deterioration discovered after scaffolding is set up will be presented with photos, quantities, and costs for approval before proceeding with the work. |
| During Construction to Completion Inspection Report |
A supervisor will inspect each stage and take construction photos. At completion, we will confirm the finish in the presence of the customer and provide construction photos, a report on the paint used, and a warranty. |
* For management associations, it is smooth to decide in advance who will approve additional work (such as the chairman or repair committee) and the amount that requires approval before signing the contract.
How will life be during construction? Impact on residents
Large-scale repairs are principally carried out while residents remain in their homes. However, there will be restrictions on daily life while scaffolding is in place. Most troubles can be prevented by providing prior notice, so Kakeru Koumuten is committed to thorough explanations and postings before construction begins.
| What will be affected | What will actually happen / Our response |
|---|---|
| Laundry | On days of high-pressure washing, painting, and waterproofing, outdoor drying will not be possible. We will inform you via bulletin boards and each unit’s mailbox about “which side will be worked on today” and will secure as many days as possible for drying. |
| Window opening and closing | In addition to washing and painting days, there may be times when windows cannot be opened during processes such as protection, drying, and waterproofing. We will provide information for each process, so please check the postings and notifications. We will organize the schedule to avoid continuous closures. |
| Balcony | During floor waterproofing and handrail painting, we ask for temporary relocation of personal items, plants, and air conditioning outdoor units. The timing will be notified in advance for each unit. |
| Noise and odor | The period of substrate repair (chipping and drilling) will produce the most noise. Working hours are generally from 8 AM to 5 PM, and we will accommodate requests such as refraining from work on Sundays and holidays. Low-odor paint options are also available. |
| Security and privacy | Scaffolding can become an access route. We can take measures such as blocking sightlines with mesh sheets and installing locks and sensor lights on the scaffolding’s access stairs at night. We also emphasize etiquette education for visitors. |
| Parking | Vehicles on the side where scaffolding will be erected will need to be temporarily relocated. Since securing a relocation spot may take time, we will start securing a relocation spot together 2 to 3 months before construction begins. |
| Pets, small children, and working from home | If you have sensitivities to noise, please inform us in advance, and we may be able to adjust the work schedule accordingly. Please feel free to let us know. |
| Rented rooms | We can assist owners in creating notification documents for residents. If you are concerned about the impact of construction on occupancy rates, we can also suggest an image change with color simulations. |
How to choose a large-scale repair contractor and ordering method
There are many large-scale repair contractors covering Koganei City, Tokyo, and you may be unsure which contractor to choose. When requesting renovations for apartments, condominiums, or buildings, please check the following four points.
● Have extensive experience in large-scale repairs
● Confirm the presence of warranties and aftercare services
● Obtain estimates from multiple contractors (at least 3 companies)
● Confirm whether they manage their own work
Have extensive experience in large-scale repairs
Large-scale repair contractors often have websites that showcase their exterior renovation achievements. If they provide detailed explanations of repair contents with photos, it gives peace of mind as it can serve as a reference when actually making a request.
Using ratings from Google and review sites can be effective when comparing large-scale repair contractors!Be cautious if there are many negative reviews. If there are few reviews, also check the construction track record, content of explanations, and management system.
Large-scale repair work can lead to troubles not only with the construction itself but also with residents and nearby neighbors, so it is necessary to post updates on the progress of the work and information about laundry on bulletin boards to prevent issues before they arise. Kakeru Koumuten specializes in exterior work, and we receive many requests for exterior renovations of apartments and condominiums.
Check for warranties and aftercare services
When choosing a large-scale repair company, check for the presence of a warranty. If any issues such as leaks occur after the work is completed, having a leak warranty from the contractor ensures that repairs can be made at no cost, providing peace of mind! A company that offers a warranty is a sign of confidence in their work, making it a criterion for selecting a contractor.
Warranty periods vary by contractor and type of work, but typically range from 1 to 10 years. Emergency repairs or partial fixes often do not come with a leak warranty. Some contractors also offer aftercare services separate from the warranty, so be sure to check for warranties and aftercare services.
Kakeru Koumuten sends out annual direct mail for aftercare maintenance, allowing for yearly inspections. We provide simple repairs such as partial sealing at no charge.
Obtain estimates from multiple contractors (at least 3 companies)
When requesting large-scale repairs, be sure to obtain estimates from multiple contractors. It is important to get estimates from at least 3 companies and compare their estimates and reports! Even for the same type of work, costs can vary between contractors, and warranties and aftercare services may differ. Additionally, obtaining multiple estimates makes price negotiations easier.
When comparing estimates, consider not only the cost but also the “items in the estimate,” “methods and materials for substrate repairs and exterior wall painting,” and “confirmation of the process”—compare these details closely to make a judgment! If the rank of auxiliary materials is low or if steps are skipped, costs can be reduced, so avoid making decisions based solely on price. Especially since substrate repair work can be difficult to assess from appearance alone, be sure to check whether the repair method is suitable for the condition of the substrate!
Check this on the estimate (checklist)
| Confirmation Items | Points to Consider |
|---|---|
| Is there an excessive use of “one set” notation? | Are the quantities and unit prices clearly stated? With “Exterior Wall Repair One Set,” comparisons and verifications cannot be made. |
| Do the quantities match the actual measurements? | Are there quantities recorded that are far from the drawings or actual measurements? This is the area where inflation is most likely to occur. |
| Proportion of miscellaneous expenses | Details and proportions of site management costs, general management costs, and statutory welfare costs. According to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for the fiscal year 2021, the average is about 10% of the construction cost (excluding common temporary costs), but it varies depending on the scale and conditions of the building, so there is no uniform standard. |
| Are the names of materials written down? | Are the manufacturer names, product names, grades, and number of coats for paints and waterproofing materials listed? |
| Treatment of quantities for substrate repairs | This is an item that cannot be accurately measured until scaffolding is set up. Is it stated whether it is “estimated quantity” or “actual quantity settlement,” and are there agreements for increases or decreases? This is the most important point. |
| Guarantee and after-inspection | Warranty period for each construction, frequency of inspections, and scope of free support. |
| Company backing | Types of construction industry licenses, track record of similar scale and structure, presence of qualified personnel. |
Confirm if it is managed in-house
Large-scale renovation work includes various tasks such as “substrate repair work,” “exterior wall painting,” “waterproofing work,” and “pipe replacement,” and the plan content will change based on the actual deterioration condition and customer preferences.
If a contractor completely outsources to subcontractors, they may lack knowledge and experience, leading to proposals for repairs in irrelevant areas or unnecessary work. If you investigate and then request a subcontractor, it may incur additional time and costs. By having knowledge and experience and managing in-house, responsible construction can be carried out at a reduced cost.
Moreover, contractors that outsource may also be slow to respond if any troubles occur during construction. It is safer to avoid having a company that has not actually met with the customer manage the construction. Kakeru Koumuten performs everything from temporary scaffolding installation to exterior wall painting and waterproofing work in-house, with knowledgeable and experienced personnel managing the construction!
There are three ordering methods. The choice affects the approach.
Especially for management associations, it is necessary to decide “how to request” before “which company to hire.” The main ordering methods are the following three.
| Method | Procedure | Advantages | Disadvantages |
|---|---|---|---|
| Responsible Construction Method | The construction company handles investigation, design, construction, and management all at once | No additional costs for commissioning design consultants (investigation and design costs may be included in the construction costs) / Single point of contact reduces the burden on the management association / Responsibility is clear / May shorten the time until ordering | Specifications can easily be left to the construction company, making it difficult to compare side by side / Third-party checks are hard to implement, requiring the management association to verify price, specifications, and construction status |
| Design Supervision Method | A design office or consultant conducts the investigation and design, while a separate company handles the construction | Allows comparison of construction companies under the same conditions / Independent supervision during construction | Consulting fees are required separately / Attention needed for risks of conflicts of interest and collusion / Tends to prolong the duration |
| Management Company Prime Contract Method | The management company acts as the prime contractor, with subcontractors performing the construction | Easy coordination with daily management / Minimal effort required from the management association | Intermediate margins can lead to higher costs / Competition principles may not be effectively applied |
Collusion and Inappropriate Consulting Issues in Large-Scale Renovations and Self-Defense Measures
Latest 2026 In the large-scale renovation industry, inappropriate orders linked between design consultants and construction companies have long been a problem. The Ministry of Land, Infrastructure, Transport and Tourism issued warnings and notifications to management associations in January 2017 and April 2023, and on September 28, 2026, the Japan Fair Trade Commission announced that it had issued exclusion orders to 38 companies and payment orders for a total of 1.63788 billion yen to 37 companies regarding large-scale renovation work commissioned by condominium management associations in the Kanto region to design consulting firms (two design consulting firms were also subject to exclusion orders).
※Based on the announcement by the Japan Fair Trade Commission (September 28, 2026).
Three Typical Methods
① Dummy Estimates
Prior to placing an order, companies are predetermined, and other companies only provide a formal high estimate in a “fixed race.” This gives the impression to the management association that they have “properly obtained competitive estimates.”
② Collusion with Design Supervisors
Consultants contract at extremely low design supervision fees while receiving kickbacks from the high construction costs of affiliated contractors. Be cautious of design supervision fees that are too low.
③ Back Margin
A certain percentage of the contract amount is given as a kickback, which is then added to the construction costs as an expense. As a result, the management association ends up paying extra.
Self-Defense Measures for Management Associations
- Obtain independent estimates from multiple companies
- Consult with neutral third parties such as condominium management professionals or architects
- Document the contractor selection process in minutes to ensure transparency
- Confirm the reasons for unusually low consulting fees
- Include a penalty clause in the contract for cases of collusion
- Avoid concentrating information with a single consultant and verify specifications independently
Frequently Asked Questions about Large-Scale Repairs in Koganei City, Tokyo
- How much does large-scale repair in Koganei City, Tokyo cost?
- For condominiums, according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for the fiscal year 2021, about 70% of cases fall within the range of 750,000 to 1,500,000 yen (excluding consumption tax and common temporary construction costs), with the most common range being 1,000,000 to 1,250,000 yen. Based on our company’s construction records, the cost for a two-story wooden apartment ranges from 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment from 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings from 5,000,000 to 15,000,000 yen. The cost varies depending on the condition of the substrate and whether waterproofing or roofing work is required, so we will provide an estimate through a free on-site survey.
- How often should large-scale repairs be conducted?
- Generally, a cycle of 12 to 15 years is recommended, and the actual cycle is most commonly 13 years according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey, with about 70% falling within the 12 to 15-year range. However, the decision should be based on the condition of deterioration rather than just the number of years. If signs of deterioration such as sealing degradation, tile lifting, or waterproof layer breakage are observed, it is advisable to carry out repairs without waiting for the cycle, as this can ultimately reduce costs. In Koganei City, the Tokyo survey (published in March 2013) identified 202 buildings, of which 34 are classified as old seismic standards. According to the city’s survey (conducted in 2010), the most common construction years are from 1991 to 2000, which translates to buildings that are 26 to 35 years old, while those built between 1981 and 1989 fall into the 36 to 45-year category. In these categories, it is expected that the second to third round of repairs will involve replacing waterproof layers and sealing, as well as updating equipment. However, the survey is from 16 years ago, and the current situation varies by building.
- How long does the construction period take? Can residents stay during the work?
- The estimated duration is about 3 weeks to 2 months for apartments, 1.5 to 3 months for small condominiums or buildings, and approximately 4 to 6 months for condominiums with over 50 units. Residents can remain in their homes during the construction. However, while scaffolding is in place, there may be restrictions on drying laundry outside and opening windows, so we take thorough measures to minimize the impact on daily life, including distributing pre-construction notices, providing information on the schedule and laundry through bulletin boards, and strictly adhering to working hours.
- How long should I expect from the start of planning to the completion of construction?
- For management associations, the process from establishing a repair committee, conducting building diagnostics, selecting contractors, to passing resolutions at general meetings typically takes 1 to 1.5 years, followed by 3 to 6 months for construction. Overall, it is advisable to plan for about 2 years to proceed comfortably. If you are using subsidies or tax incentives, obtaining management plan certification (resolutions at general meetings, pre-confirmation, and certification application) will also take time, so please factor that into your timeline.
- Are there any subsidies available for large-scale repairs in Koganei City, Tokyo?
- Based on the official page of Koganei City, there does not appear to be a municipal program that subsidizes the construction costs or deterioration diagnosis costs for large-scale repairs of condominium buildings (as of October 15, 2026. Please confirm with the city’s Urban Development Promotion Division, Housing Section). The city provides information on the condominium management status reporting system, management plan certification system, and condominium management improvement promotion plan, among others. The city’s seismic assistance is targeted at wooden houses and similar structures. For large-scale repairs, if the condominium meets the requirements, you can consider a reduction in fixed property tax under the “Condominium Longevity Promotion Tax System” (in Koganei City, the city tax reduction rate is one-third. The urban planning tax is not reduced) or loans from the Japan Housing Finance Agency, as well as the Tokyo Metropolitan Government’s “Condominium Improvement Construction Subsidy” (interest subsidy. Applications for the second phase of fiscal year 2026 are accepted until February 19, 2027). Management plan certification is handled by Koganei City (Urban Development Promotion Division, Housing Section 042-387-9861). The city’s “Subsidy for the Promotion of New Energy Equipment for Residential Use” is an individual program, and applications for fiscal year 2026 have closed as the budget limit has been reached (as of October 15, 2026). Additionally, for construction that includes windows and insulation, there may be eligibility for the national programs “Advanced Window Renovation 2026,” “Mirai Eco Housing 2026,” and the Tokyo Metropolitan Government’s energy-saving renovation promotion project for existing homes. The timing of applications and applicants varies by program, so please check the eligibility conditions and application procedures for each program before contracting and starting construction.
- I heard that fixed property tax can be reduced through large-scale repairs. Is that true?
- 要件を満たす場合は減額されます。マンション長寿命化促進税制により、築20年以上・総戸数10戸以上などの要件を満たす分譲マンションが長寿命化に資する大規模修繕（外壁塗装等・床防水・屋根防水の3工事を一体で実施）を行うと、翌年度の建物の固定資産税額が1戸100㎡相当分まで減額されます。減額割合は自治体の条例で決まり、小金井市（固定資産税は市税）では3分の1です（都市計画税は減額されません）。対象は令和5年4月1日から令和9年（2027年）3月31日までに完了した工事で、申告先は小金井市役所 資産税課 家屋係（042-387-9821）、申告期限は工事完了後3か月以内です。管理計画認定マンションの場合は修繕積立金の引上げなどの要件もあり、準備に時間がかかりますので、工事の1年以上前から動くことをおすすめします。
- Are there any changes to subsidies starting in 2026?
- Yes. The national “Childcare Green Housing Support Project” has been abolished and reorganized into the successor “Mirai Eco Housing 2026 Project.” Since management associations and management corporations can also become joint contractors, it can be used for insulation renovations in common areas. Additionally, the “Long-Term Excellent Housing Renovation Promotion Project” will end in the 2025 fiscal year and will not be implemented in the 2026 fiscal year. The “Advanced Window Renovation 2026 Project” has a method for collective applications for apartment buildings (application procedures will be handled by registered contractors). Please be careful not to establish financial plans based on outdated information.
- What should I do if the repair reserve fund is insufficient?
- There are mainly four options: ① Postpone low-urgency work based on a deterioration diagnosis, ② Review the scope and specifications of the work, ③ Check for support systems such as subsidies, ④ Consider increasing the repair reserve fund or financing from the Japan Housing Finance Agency. The agency’s financing for apartment common area renovations does not require collateral, and interest rates can be reduced by up to 0.6% per year by obtaining management plan certification and implementing energy-saving or earthquake-resistant work. Please note that postponing waterproofing and tile peeling measures often ends up being more expensive, so please consult us regarding the decision to separate these tasks.
- Can scaffolding be set up if there is a height difference on the site or if the front road is narrow?
- Yes, it can. Koganei City has a height difference due to the Kokubunji Cliff Line, and low-rise residential areas are widespread, so the conditions for scaffolding plans vary depending on the location, such as the width of the front road and the distance to neighboring buildings. The focus of the scaffolding plan is the width of the front road, the distance to neighboring buildings, the delivery route, and whether a road occupancy permit is required. If scaffolding or temporary enclosures occupy the road, a road occupancy permit from the road administrator (for city roads, Koganei City Road Management Division, for prefectural and national roads, the respective road administrators) and a road usage permit from the jurisdictional police station are required. For city road occupancy in Koganei City, an occupancy permit application and consultation documents (two copies each) must be submitted to the counter, and applications by mail are generally not accepted. If scaffolding or temporary enclosures are to be placed on the sidewalk, the opinion of the Koganei Police Station is always required, and it is necessary on the roadway if deemed necessary. According to the city’s permit standards, the projection on the sidewalk must be less than 1m from the road edge and less than one-third of the effective width, ensuring a passage width of at least 1.5m excluding the occupied items. The projection on the roadway must be less than 1m from the road edge and less than one-eighth of the road width, and there are height conditions for cantilever scaffolding. The standard processing period and occupancy fee amounts are not listed on the city’s page, so please confirm in advance at the counter. The conditions of the site and delivery routes differ for each building. Kakeru Koumuten Co., Ltd. owns its scaffolding materials and has its own scaffolding team, allowing us to plan the layout, delivery route, and delivery time after confirming the site. This is an area where additional costs are likely to arise after seeing the site, so it is important to confirm the delivery route, the need for occupancy, and the application schedule during the estimation stage.
- What will happen to the parking for residents during construction?
- Vehicles on the side where scaffolding will be erected will need to be temporarily moved. The number of parking spaces and availability varies by building, and securing a relocation destination may take time depending on the availability of nearby parking lots. Kakeru Koumuten Co., Ltd. will coordinate with you regarding the availability of nearby coin parking and monthly parking lots starting 2 to 3 months before construction begins.
- Can I freely decide the color of the exterior walls?
- 小金井市の公式ページでは、市独自の景観計画や景観条例は確認できませんでした。東京都景観計画の区域では、東京都景観条例にもとづく届出が、建築物全体の規模によって必要になる場合があります。建築物は、新築・増築のほか、外観を変更することとなる修繕・模様替や色彩の変更が対象で、東京都のQ&Aでは、同じ色の塗り替えも届出の対象とされています（タイル補修などの通常の管理行為は対象外）。届出は工事着手の30日前までで、対象かどうかは変更する部分の面積ではなく、建築物全体の規模で判断されます。景観基本軸にかかる場所は別の扱いになる場合があるため、敷地ごとに東京都（緑地景観課 03-5388-3265）の地区区分でご確認ください。このほか、小金井市の地区計画の区域では、建築物の建築や形態又は意匠の変更を行う場合に、工事着手の30日前までの届出が必要です（まちづくり推進課 まちづくり係 042-387-9862）。外壁の塗り替えが該当するかは市のページに明記がないため、窓口での確認が必要です。届出が必要かどうかは建物の場所と工事の範囲によって異なりますので、事前にご確認ください。弊社でも調査時に併せてお調べします。カラーシミュレーションで完成イメージを共有すると、総会や近隣とのお話し合いが進みやすくなります。
- Why is only the north side of the exterior wall covered in moss and algae?
- The side with poor sunlight and trapped moisture is prone to the growth of algae, moss, and mold. In addition to the north side, areas that do not receive sunlight due to neighboring buildings or trees are also likely to be affected. By thoroughly removing them with high-pressure washing and choosing paint with anti-algae and anti-mold properties, you can suppress their recurrence. We also recommend checking for blockages in roof drains and gutters caused by fallen leaves and mud, as these can lead to puddles on the roof or leaks.
- Which method should I choose, responsibility construction or design supervision?
- For smaller buildings, the burden of consulting fees tends to be heavier, so we believe that the responsibility construction method is often more suitable. On the other hand, for large buildings with many units, the benefits of having a third party standardize specifications and compare under the same conditions become significant with the design supervision method. While the design supervision method allows for comparison of construction companies under the same conditions, it incurs separate consulting fees and requires caution regarding conflicts of interest and collusion risks. Even with the responsibility construction method, verifying price, specifications, and construction status is essential. Kakeru Koumuten Co., Ltd. provides estimates that clearly state quantities, methods, and materials for each construction item, allowing for comparison on the same level as other companies.
- How can I detect collusion in large-scale repairs?
- There are three typical methods. 1) Deciding on a contractor in advance and having other companies submit only formal high estimates, known as “dummy estimates.” 2) A consultant contracts at an extremely low design supervision fee and receives kickbacks from partner companies, creating collusion. 3) Adding a portion of the contract amount as a back margin to the construction costs. Countermeasures include obtaining independent estimates, consulting with a neutral third party, documenting the selection process in minutes, and including penalty clauses in contracts. On September 28, 2026, the Japan Fair Trade Commission announced exclusion orders and payment orders for large-scale repair work.
- How many companies should I get estimates from?
- We recommend at least three companies. If there are too many, it becomes difficult to compare; if there are too few, competition does not occur. What is important is not the number of companies but “creating the same level of comparison.” By creating a common specification sheet and quantity list and requesting under the same conditions, and requiring detailed breakdowns instead of “one set” notation, it becomes clear whether the price differences are due to variations in scope or unit prices.
- What is the difference if you have your own scaffolding?
- In large-scale repair work, temporary construction accounts for about 20% of the total cost (according to the Ministry of Land, Infrastructure, Transport and Tourism’s 2021 survey). By not outsourcing scaffolding work, it is easier to control costs in this area, and our own scaffolding team can flexibly respond to sudden changes in the schedule or additional work. Kakeru Koumuten Co., Ltd. owns scaffolding materials for about 100 detached houses and plans according to the site, even in locations with height differences or narrow front roads.
- Can I just have a look at the estimate during the competitive bidding process?
- Of course, that is possible. If you bring estimates from other companies, we will check for free whether the items, quantities, methods, and materials are appropriate and provide an estimate under the same conditions. We welcome competitive bidding.
- Can I request just emergency repairs for leaks?
- Yes. As a preliminary step before large-scale repairs, we also accept requests for emergency measures for leaks and partial repairs. We identify the cause using thermography and drones, and propose the minimum necessary repairs.
- Can you handle roofing materials and exterior wall materials that contain asbestos?
- Yes, we can. We have qualified personnel such as asbestos work supervisors and building material asbestos surveyors, and we handle everything from the legally required preliminary surveys to the cover method and removal of asbestos-containing roofing materials. As of October 15, 2026, there were no municipal subsidies for asbestos surveys or removal work found on the official page of Koganei City. Please confirm with the city or Tokyo Metropolitan Government regarding notifications related to dust prevention during the planning stage of the construction.
- What happens if large-scale repairs are not done?
- There are risks such as personal injury from falling exterior wall tiles, structural deterioration due to corrosion of rebar, leaks, and a decrease in asset value. Furthermore, for buildings subject to periodic reporting under Article 12 of the Building Standards Act, investigations through comprehensive tapping and other methods are required under certain conditions, such as if more than 10 years have passed since completion or exterior wall renovations for tiled or mortar-finished walls. The periodic reporting for buildings in Koganei City is managed by the Tokyo Metropolitan Government’s Tama Building Guidance Office, not the city. Please check the conditions for applicable uses, scales, and the number of floors or floor area that apply to multi-family dwellings in the list of periodic reporting targets or at the relevant office in Tokyo. Complex buildings including stores, restaurants, hospitals, and hotels may also be subject to reporting depending on their use and scale, so individual confirmation is necessary. Even if not subject to statutory investigations, regular inspections and maintenance are essential, so please consult us if you are unsure.
- How much does large-scale repair for an apartment (about 10 units) cost?
- For a wooden two-story building with 6 to 10 units, the estimate is between 2 million and 4 million yen, and for a three-story steel or RC building with 10 to 20 units, it is between 4 million and 9 million yen based on our company’s track record (including scaffolding, substrate repairs, exterior wall painting, sealing, and waterproofing). It is common for apartments to undergo repairs every 10 to 15 years. For owners, there is an increasing trend to change the appearance through color simulations during repairs to improve occupancy rates.
If you are looking for a large-scale repair contractor in Koganei City, contact Kakeru Koumuten Co., Ltd.
We handle exterior wall renovations and large-scale repairs for apartments and condominiums in Koganei City, covering all of Kanagawa and Tokyo. We are happy to assist not only with large-scale repair work but also with partial repairs and leak repairs. “I want it to last long with one renovation” “I want to keep costs down as much as possible” “I want to improve insulation because the indoors are hot” We will propose the best solutions for your specific requests and future repair plans.
From temporary scaffolding work to roofing and exterior wall painting, all work is performed by our own team. We are confident that we will not be outdone by others in terms of cost, quality, and organization, so we welcome comparative estimates!
On-site surveys, estimates, and color simulations are all free
Please feel free to consult us via the inquiry form, phone, or LINE.
It’s also fine to just present estimates from other companies.
Large-scale repair construction service areas
Kakeru Koumuten Co., Ltd. accepts requests throughout Kanagawa and Tokyo.
Kajino Town / Sakura Town / Sekino Town / Nakacho / Nukiiminami Town / Nukiikita Town / Higashimachi / Honcho / Maehara Town / Midori Town
・When should large-scale renovations be carried out? An explanation of the optimal timing and the risks of postponement!
・Estimates are essential when conducting large-scale renovations! Key points for comparison and precautions!
・5 common troubles in large-scale renovations for condominiums! A thorough explanation of causes and prevention measures!
・What is waterproofing work in large-scale renovations? A thorough explanation of its role, signs of deterioration, and precautions!
・Insufficient funds for large-scale renovations… An explanation of how to deal with funding shortages and preparations you can do right now!
・What is substrate repair, which is important in large-scale renovations? A thorough explanation of its necessity, signs of deterioration, and types of work!
・What is sealing work in large-scale renovations? An introduction to its role, methods, and tips for avoiding mistakes!
・What is tile repair, which is important in large-scale renovations? An explanation of signs of deterioration, types of work, and cost averages!
・What is exterior wall painting, which is important in large-scale renovations? A thorough explanation of its necessity, signs of deterioration, and cost averages!
・For exterior renovations in Koganei City, Tokyo, trust Kakeru Koumuten!
・For roof renovations in Koganei City, Tokyo, trust Kakeru Koumuten!
・For exterior wall painting in Koganei City, Tokyo, trust Kakeru Koumuten!
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contact Kakeru Koumuten Co., Ltd.
Kakeru Koumuten is a young company whose team is, on average, in their late twenties, but our skills are second to none.
Our greatest strength is that we handle scaffolding, roofing and painting entirely in-house. In an industry where these tasks are usually divided among contractors, our complete service simplifies project management and helps keep costs down. Above all, if a problem arises, we respond promptly.
We proudly describe ourselves as the youngest and most helpful renovation company in Kanagawa!
