Leave the repairs and renovations of condominiums and apartments in Chuo Ward, Sagamihara City to Kakeru Koumuten Co., Ltd.!

Large-Scale Repairs for Condominiums, Apartments, and Buildings in Chuo Ward, Sagamihara City

Large-scale repair work that can be handled in Chuo Ward, Sagamihara City

Large-scale repairs are not just “exterior wall painting” or “waterproofing,” but rather a comprehensive repair work that addresses the deterioration of the entire building while scaffolding is in place. At Kakeru Koumuten, we can handle all the following work in-house, ensuring clear responsibility and coordination of the process.

Scope of Major Repairs Determined by Building Diagnosis

It is not guaranteed that all the above works will be carried out. 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 items below, compile them into a deterioration diagnosis report with photos, and propose the scope of work.

Reasons Kakeru Koumuten is Chosen for Large-Scale Repairs in Sagamihara City, Chuo Ward

The reason why we can be entrusted with large-scale repairs in Chuo Ward is partly because “Kakeru Koumuten has a base in Yokohama City”, but also due to our “unique initiatives in large-scale repair work that cannot be imitated by other companies”, which have received high praise from many customers.

1. Equipment Specialized for Exterior Renovations

At Kakeru Koumuten, we have prepared the following warehouses and material storage areas to provide low-cost, high-quality exterior wall painting and waterproofing work for large-scale repairs. We have established five bases centered around Yokohama City for material storage and showrooms.

In-House 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 cut costs associated with scaffolding work and provide 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 can procure materials at a lower cost! Additionally, we always have stock available, allowing for swift responses in emergencies!

In-House Waste Sorting

Large-scale repairs generate various waste materials such as leftover paint, metals, and wood. At Kakeru Koumuten, we sort and recycle waste materials in-house, which helps reduce waste disposal costs.

Showroom Dedicated to Exterior Renovations

In the showroom, not only can you have meetings, but you can 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 by Kakeru Koumuten, we can keep costs down while ensuring 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, 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 will conduct inspections and actual construction for each process!

3. Obtaining Various Permits and Skilled Workers

We have obtained permits for the construction industry and for the collection and transportation of industrial waste! We also have national certified sheet metal workers 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 surveys for roofing materials containing asbestos.

4. Warranty and Aftercare

Large-scale repair work comes with warranties for most jobs, including “painting work,” “substrate repair work,” and “waterproofing work”!
Aftercare is available every year, and we send out notification DM each year.

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 rain 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 rain leaks! We will respond quickly to urgent requests!

6. Staff Development

Our staff create various models to improve their skills and conduct practical training. Since different processing and techniques are required at each site, we regularly provide skill enhancement education to ensure that each staff member can respond appropriately. We also educate on points to pay attention to and areas to check during each stage of large-scale repair work.

7. Consideration for Residents and Neighbors

During large-scale repair work, we not only notify residents and greet neighbors, but we also set up notice boards at entrances to display progress charts and announcements! Additionally, we thoroughly educate entrants on manners to minimize inconvenience to residents and neighbors.

8. Strict Quality Control

Inspections are conducted by responsible personnel at each stage, along with detailed photographs of the work. We use film thickness inspection equipment and check sheets to ensure that no inspections are overlooked. During exterior wall painting and waterproofing work, we check the number of used paint cans to confirm that the specified amount of paint is used, and we prevent construction defects by ordering paint in-house. Of course, we will also photograph and report the used paint.

9. Exterior Wall Painting Color Simulation

9-1 Self Color Simulation

The simulations created by our company can be done using actual photos of your apartment or building!You can also perform simulations on your smartphone or computer. By simulating and then changing to a two-tone color or making an image change, we hope to help enhance the stylish appearance and increase the occupancy rate! Of course, we can also arrange paint samples for actual color confirmation.

*In Chuo Ward, there are areas where rules for urban development, such as district plans, are established. Since the regulations differ by district, prior confirmation of the exterior wall color may be necessary. Having a color simulation screen will help facilitate explanations at neighborhood associations and general meetings.

9-2 Confirm the actual color with a test paint!

You can order samples of the paint you are considering and conduct test painting on your exterior wall. By conducting a test paint, you can confirm the actual color and gloss!

9-3 Exterior renovation simulation

We can also simulate the following exteriors for apartments and condominiums!
・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 and roof replacement work

With the exterior renovation simulation, you can minimize the risk of failure in image changes! We hope that renovating the appearance of your apartment or condominium will help increase the occupancy rate.

Estimated Costs for Large-Scale Renovations in Chuo Ward, Sagamihara City

The costs for large-scale renovations vary significantly based on the size of the building, its condition, the scope of work, and the materials used. First, please refer to the national average based on public statistics, then to our company’s estimates based on past projects categorized by size, and finally to examples of unit prices for specific renovations.

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 cases (FY 2021), approximately 70% of the costs for large-scale renovations 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. Please note that the amounts in this survey do not include consumption tax and common temporary costs, so they differ from the current total construction costs including tax.

Source: Ministry of Land, Infrastructure, Transport and Tourism “Survey on Large-Scale Renovations of Condominiums for FY 2021” (200 companies, 818 cases)　*Amounts do not include consumption tax or common temporary costs. Percentages may not total 100% due to rounding and non-responses.

Breakdown of Construction Costs (What the Money is Spent On)

Source: Ministry of Land, Infrastructure, Transport and Tourism “Fiscal Year 2021 Survey on Large-Scale Repair Works for Condominiums” (Second aggregation of large-scale repair works. The overall average is 59.0% for construction-related, 22.3% for temporary structures, and 9.9% for miscellaneous expenses). *The total does not equal 100% because it includes equipment-related works, exterior works, and others. 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 Wall Painting, Waterproofing, Sealing as a Whole)

*The above is a rough estimate based on Kakeru Koumuten’s construction performance and may vary depending on the presence of roofing works, metal works, plumbing, etc. For condominiums, please also consider the amount obtained by multiplying the above 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 wall painting,” “waterproofing,” and “miscellaneous expenses.” Before comparing total amounts, please check what each item includes, how much, and at what cost.

Examples of Unit Prices for Repair Work

*Costs and warranty periods vary depending on shape, quantity, substrate condition, and type of materials. If you would like 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 ≠ correct choice.” The best way to choose is to align when the next major repair will be with the lifespan of the materials to minimize waste.

* The estimated lifespan is a general guideline and may vary depending on sunlight, location, and substrate condition. The rate of deterioration differs for each side due to location, sunlight, and airflow, so conducting a site survey to check the condition of each side and selecting paint suitable for the location will affect durability.

Guideline for Repair Reserve Fund and Options When Insufficient

The Ministry of Land, Infrastructure, Transport and Tourism guidelines indicate the guideline for repair reserve funds on a monthly basis per exclusive area. Additional charges are required if there is a mechanical parking lot.

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 comprehensive survey for the fiscal year 2023, 36.6% of management associations responded that “the repair reserve fund is insufficient compared to the plan.” There are four main options if there is a shortfall.

Subsidies, Tax Systems, and Loans to Check for Large-Scale Renovations in Chuo Ward, Sagamihara City

Both Sagamihara City and Kanagawa Prefecture do not list subsidies specifically for large-scale renovation work in the publicly available list of grant systems. The available options can be broadly categorized into four types. The eligibility and application status of these systems may change during the fiscal year, so please be sure to confirm with our company or the respective offices before contracting or starting work. (As of October 8, 2026)

① Condominium Longevity Promotion Tax System (Reduction of Fixed Property Tax)

If large-scale repairs (including exterior painting, floor waterproofing, and roof waterproofing) that contribute to the longevity of condominiums meeting certain requirements are carried out, the fixed property tax for the residential portion will be reduced by half (up to the equivalent of 100㎡ per unit). The reduction applies to the fiscal year with a valuation date of January 1 of the year following the completion of the work.

* The national leaflet shows the range of reduction rates as a nationwide system. The reduction rate for Sagamihara City is 50%. The application should be submitted to the city’s property tax division (Building Assessment Group 1 & 2, Phone 042-769-8224).

② Support and Subsidies for Condominium Management in Sagamihara City (Management Associations should start here)

The support related to condominiums in Sagamihara City is handled by the city’s Housing Division (Phone 042-769-9817). It focuses on support for consultation, planning, and specific purposes such as seismic resistance and EV charging, rather than subsidies for the construction costs of large-scale repairs.

Source: Sagamihara City “Plans and Policies Related to Condominiums”／Same “Condominium Advisor Dispatch System”／Same “Support for Earthquake Countermeasures for Condominiums Built to Old Seismic Standards”／Same “Subsidy for Electric Vehicle Charging Equipment Installation”

③ Management Plan Certification System (Tax and Interest Rate Benefits)

This is a system certified by Sagamihara City. Upon receiving certification, there are interest rate benefits for the “Condominium Common Area Renovation Loan” from the Japan Housing Finance Agency and Flat 35 (Maintenance and Preservation Type), which also relates to one of the requirements for the Long Lifespan Promotion Tax System (certification alone does not guarantee tax reduction). The main criteria include holding general meetings at least once a year, maintaining management regulations, separate accounting for management fees and repair reserves, overdue amounts of more than three months being within 10% of the total, and “having a long-term repair plan that includes large-scale repair work at least twice and is created or reviewed within seven years, with a planning period of 30 years or more.” Additionally, Sagamihara City has its own criteria requiring initiatives for disaster prevention (such as creating disaster prevention plans, organizing voluntary disaster prevention groups, stockpiling disaster supplies, and conducting disaster drills).

*The application fee for certification to the city is 3,600 yen if there is one long-term repair plan. Prior consultation with the Housing Division and pre-confirmation with the (Public Interest Incorporated Foundation) Condominium Management Center (online) is required before applying.

④ National Energy Saving Support | Housing Energy Saving 2026 Campaign

Changes for FY 2026The “Child-Rearing Green Housing Support Project” for FY 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 FY 2027 and will not be implemented in FY 2028. Please be careful not to base your financial plans on outdated information.

Mirai Eco Housing 2026 Project

Advanced Window Renovation 2026 Project

⑤ Kanagawa Prefecture Subsidies (Applications for Fiscal 2026 have ended)

* The Existing Housing Energy Saving Renovation Subsidy does not apply to common areas of rental apartments or units not occupied by the owner.

⑥ Financing System (Housing Finance Agency Condominium Sumairu Loan)

If the management association borrows funds for large-scale repairs, the Housing Finance Agency’s “Condominium Common Area Renovation Loan (Condominium Sumairu Loan)” can be utilized.

Source: Housing Finance Agency “Condominium Sumairu Loan” (Official)

Cases Where Fire Insurance Can Be Used and Cases Where It Should Not Be Used

Building Conditions and Repair Points in Chuo Ward, Sagamihara City

Chuo Ward, Sagamihara City, is located at the center of Sagamihara City, and is the administrative center where municipal, national, and prefectural government offices such as the city hall and tax office are concentrated. It covers an area of approximately 36.9 km², accounting for 11.2% of the city area, and has the second largest population among the three wards in the city. The area around Sagamihara Station on the JR Yokohama Line is the city’s central urban area where commercial, business, and administrative functions are gathered. To the north of the ward is the Sagami General Supply Depot (196.7 hectares), and about 17 hectares were returned in September 2014 to the north of Sagamihara Station. On the other hand, there are industrial parks in Tana, Miyashita, and Koyama, while the southern part features the Sagami River, with agricultural land and sloped forests remaining. Since the urban area, residential area, housing complexes, and industrial areas are all located within the same ward, the way buildings deteriorate and the method of scaffolding will vary depending on the location.

Source: Sagami City “Population and Number of Households” as of September 1, Reiwa 8 (estimated based on the Reiwa 7 national census preliminary figures)／Same “Profile of Chuo Ward”／Same “Current Status of the North Exit Area of Sagamihara Station”

Buildings in Chuo Ward are divided into “four types”

In Chuo Ward, due to the different historical developments of the town in various locations, not only the age of the buildings but also the location of the buildings (central urban area around Sagamihara Station, residential areas around Fuchinobe and Kamimizo, older housing complexes and large condominiums, and industrial and agricultural areas in Tana and Miyashita) will affect the scale of repairs needed for the next major renovation. Please check which type your building falls into.

Source: Sagamihara City “Profile of Chuo Ward”／Same “Urban Planning Master Plan for Chuo Ward”／Same “Current Status of the North Exit Area of Sagamihara Station”

Four Unique Factors in Chuo Ward That Damage Buildings

From the publicly available materials of Sagamihara City, we have narrowed down four characteristics of Chuo Ward that are linked to large-scale repairs.

Source: Sagamihara City “Urban Planning Master Plan for Chuo Ward”／Same “Profile of Chuo Ward”

Key Points to Consider When Advancing Construction in Chuo Ward

* Kakeru Koumuten has five locations in Yokohama City and serves the entire Chuo Ward, including Sagamihara, Fuchinobe, Yabe, Kamimizo, Minamihashimoto, and Tana.

Deterioration Symptoms and Timing Requiring Major Repairs

Generally, large-scale repairs are recommended every 12 to 15 years. According to a survey by the Ministry of Land, Infrastructure, Transport and Tourism, 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 decision should be based on the condition of deterioration rather than just the number of years, so if you observe any of the symptoms below, we recommend an early on-site inspection.

Estimated repair cycles by part (Ministry of Land, Infrastructure, Transport and Tourism guidelines)

* The above are reference examples from the guidelines and are not uniform construction deadlines. Actual cycles will be set according to the specifications, location conditions, and deterioration status of the building.

Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines for Creating Long-Term Repair Plans” (Reiwa 6, June revision, PDF) / Ministry of Land, Infrastructure, Transport and Tourism “Survey on Large-Scale Renovation Work for Condominiums in FY2021”

Examples of Large-Scale Renovation Work

This is an example of exterior renovation work on a mixed-use building undertaken by Kakeru Koumuten Co., Ltd. The building had leaks occurring in several places, and we combined clear waterproofing for the tile exterior walls with waterproofing for the roof for the renovation.

Exterior Renovation Work on a Mixed-Use Building (Tile Exterior Wall Waterproofing + Roof Waterproofing)

Customer Feedback

Flow from On-site Investigation to Completion of Construction

From the initial inquiry to the completion of construction and aftercare, one representative will consistently handle your case. In the case of management associations, a resolution at the general meeting is required, so starting the process 1 to 1.5 years before the desired start date allows for a smoother progression.

1. Contact Us (Free) Please reach out via phone, form, or LINE. If you have estimates from other companies, it’s fine to just present those.
2. On-site Survey & Building Diagnosis (Free) We will conduct a survey of the exterior walls, check for cracks, sealing, and waterproofing layers, and if necessary, investigate the roof, high places, and leak areas using drones or thermal imaging. For properties in Chuo Ward, we will also check whether they are located near the station or along major roads, the distance to neighboring properties, the width of the road and delivery routes, pedestrian traffic, drainage, rust on metal parts and fittings, and parking lots.
3. Survey Report & Estimate Submission We will provide a deterioration diagnosis report with photos and an estimate detailing quantities, methods, and materials for each work item. Multiple plan proposals are also possible.
4. Plan Decision & Contract Confirm colors through color simulations, paint samples, and trial painting. For management associations, we can assist in preparing materials for general meetings. In areas subject to district planning, landscape planning, or building agreements, we will also explain the considerations for color choices.
5. Notification to Residents & Neighbors We will distribute construction notices, visit neighbors to greet them, and set up a bulletin board at the entrance (with a schedule and laundry information). If temporary relocation of parking is necessary, we will coordinate this at this stage.
6. Temporary Scaffold Installation & Various Works Our own scaffold team will set up the scaffolding, followed by high-pressure washing → substrate repair → sealing → exterior wall painting & tile repair → waterproofing → metal parts & ancillary work in that order. A responsible person will inspect each process and take construction photos.
7. Completion Inspection, Scaffold 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 certificate.
8. Aftercare Maintenance We will send annual DM notifications, and inspections can be conducted every year. Simple repairs such as partial sealing are provided free of charge.

Resident Communication, Additional Work Approval, Inspection Reports

Just as important as the construction itself is “when, what, and with what materials we report”. At Kakeru Koumuten, we will provide materials and reports in the following four situations.

* For management associations, it is smooth to decide in advance who will approve additional work (such as the chairman or repair committee) and the estimated amount that will require approval before 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 limitations on daily life while scaffolding is in place. Most troubles can be prevented by providing prior notice, so Kakeru Koumuten Co., Ltd. thoroughly explains and posts information before construction begins.

How to Choose a Large-Scale Repair Contractor and Ordering Method

There are many large-scale repair contractors that cover the Sagamihara City Chuo Ward area, and you may be unsure which contractor to choose. When requesting renovations for apartments, condominiums, or buildings, please check the following four points.

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 offers reassurance as a reference when you actually request work.

Using Google and review site ratings 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, the content of the explanations, and the management system.

Large-scale repair work involves not only the construction itself but also potential troubles with residents and nearby neighbors. 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 Co., Ltd. specializes in exterior work, so we receive many requests for exterior renovations of apartments and condominiums.

Check for warranties and aftercare services

When choosing a large-scale repair company, make sure to check for warranties. 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! Companies that offer warranty periods are often confident in their work, making this a key 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 leak warranties. Some contractors also offer aftercare services separate from warranties, so be sure to check for warranties and aftercare services.

At Kakeru Koumuten Co., Ltd., we send out annual direct mail for aftercare maintenance, allowing for yearly inspections. We also provide free assistance for simple repairs like partial sealing.

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.” Be thorough in your comparisons! Costs can be lowered by using lower-grade materials or skipping processes, so avoid making decisions based solely on price. Especially for substrate repair work, which can be difficult to assess from the exterior, ensure that the proposed repair method is suitable for the condition of the substrate!

Check these points on the estimate (checklist)

Check if it is managed in-house

Large-scale repair 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.

There are cases where contractors that completely outsource to subcontractors lack knowledge and experience, leading to proposals for repairs in irrelevant areas or unnecessary work. If you request a subcontractor after investigation, 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.

Additionally, contractors that outsource to subcontractors may also have delayed responses in case of any troubles 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 setup 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.

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 imposed a total of 1.63788 billion yen in surcharge payment orders to 37 companies regarding large-scale renovation work commissioned by condominium management associations to design consulting firms in the Kanto region (two design consulting firms were also subject to exclusion orders).

*This content is based on the Japan Fair Trade Commission announcement (September 28, 2026).

Three Typical Methods

Source: Ministry of Land, Infrastructure, Transport and Tourism “On the Proper Ordering of Large-Scale Repair Work for Condominiums” (Notification dated April 3, Reiwa 5, PDF)

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 abnormally low fees from consultants
• Include a penalty clause in the contract for cases of collusion
• Avoid concentrating information with a single consultant and verify specifications by the management association itself

Frequently Asked Questions about Large-Scale Repairs in Chuo Ward, Sagamihara City

How much does large-scale repair in Chuo Ward, Sagamihara City cost?

For condominiums, according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for fiscal year 2021, about 70% 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 construction records, for a two-story wooden apartment, the cost is approximately 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment, it is about 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings, it ranges 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 provide free on-site estimates.

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 there are signs of deterioration in sealing, tile lifting, or breaks in the waterproof layer, it is advisable to carry out repairs without waiting for the cycle, as this can ultimately reduce costs. Older buildings tend to have a greater proportion of tile repairs and metal part replacements in the second and third repairs.

What is the construction period? Can residents stay during the work?

The construction period is approximately 3 weeks to 2 months for apartments, 1.5 to 3 months for small condominiums or buildings, and about 4 to 6 months for condominiums with more than 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 advance notices, providing information on the schedule and laundry on 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, it typically takes about 1 to 1.5 years for the establishment of the repair committee, building diagnosis, contractor selection, and general meeting resolutions, followed by 3 to 6 months for construction. Overall, it is advisable to plan for about 2 years to proceed with ample time. If you are using subsidies or tax incentives, please also factor in the time required to obtain management plan certification (which requires prior confirmation and general meeting resolutions).

Are there any subsidies available for large-scale repairs in Chuo Ward, Sagamihara City?

Neither Sagamihara City nor Kanagawa Prefecture has subsidies specifically for large-scale repair work listed in the publicly available grant system. However, for condominium owners, if certain conditions are met, a 50% reduction in fixed property tax can be applied under the “Condominium Longevity Promotion Tax System.” Additionally, Sagamihara City offers a condominium advisor dispatch system (first consultation free), seismic support for condominiums built to old seismic standards, management plan certification systems, and subsidies for the installation of electric vehicle charging facilities in multi-family housing parking lots. If the work includes windows or insulation, it may qualify for “Advanced Window Renovation 2026” or “Mirai Eco Housing 2026.” The timing of applications and applicants varies by program, so please check the eligibility conditions and application procedures for each program before contracting or starting construction.

I heard that fixed property taxes can be reduced through large-scale repairs. Is that true?

Yes, it is true if the conditions are met. Under the Condominium Longevity Promotion Tax System, if a condominium that is over 20 years old and has more than 10 units conducts large-scale repairs (including exterior painting, floor waterproofing, and roof waterproofing) that contribute to its longevity, the fixed property tax for the residential portion can be reduced by half for up to 100 square meters per unit. This applies to work completed between April 1, 2023, and March 31, 2027, and a declaration must be made to the Sagamihara City Asset Tax Division (Building Evaluation Section) within three months of completion. For certified management plan condominiums, there are additional requirements such as raising repair reserves, so it is recommended to start preparations more than a year in advance.

Are there any changes to subsidies starting from fiscal year 2026?

Yes, there are changes. The national “Child-Rearing Green Housing Support Project” has been abolished and reorganized into the successor “Mirai Eco Housing 2026 Project.” Management associations and management corporations can also become joint project participants, allowing for insulation renovations in common areas. Additionally, the “Long-Term Excellent Housing Renovation Promotion Project” will end in fiscal year 2025, and it will not be implemented in fiscal year 2026. The “Advanced Window Renovation 2026 Project” began accepting bulk applications for multi-family housing starting May 29, 2026 (application procedures will be handled by registered contractors). Please be careful not to base your financial planning on outdated information.

What should I do if the repair reserve fund is insufficient?

There are mainly four options: ① Postpone low-urgency repairs 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 condominium common area renovation loans do 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 seismic work. Please note that postponing waterproofing and tile detachment measures often ends up being more costly, so please consult us for a decision.

Can you handle large-scale repairs for complexes or large condominiums with many buildings and units?

We can discuss this. The Sagamihara City Urban Planning Master Plan (Chuo Ward) states that it supports the regeneration of older complexes in collaboration with relevant agencies, and there are many large-scale residential buildings in Chuo Ward. We also accept consultations for properties with many buildings and units. For properties with many buildings, it is important to conduct deterioration diagnoses for each building, plan whether to carry out the work collectively or divide it by building or year, and achieve consensus at the general meeting. Kakeru Koumuten Co., Ltd. also targets condominiums with over 100 units for cost estimates and will provide proposals that allow for comparison of multiple plans.

What happens to residents’ parking during construction?

Vehicles on the side where scaffolding will be set up will need to be temporarily moved. In buildings with limited parking availability, it may take time to secure alternative parking. Kakeru Koumuten Co., Ltd. will coordinate with you about 2 to 3 months before construction starts, including checking the availability of nearby coin parking and monthly parking lots.

Can I freely decide the color of the exterior walls?

The color of the building is generally decided by the management association or the owner; however, if there are district plans, landscape plans, or architectural agreements affecting the site, there may be restrictions on the appearance and color. The specifics vary by district, plan, and agreement. Sagamihara City’s “Sagamihara Map Information” provides documents to check the status of urban planning designations, and we will also investigate this during our research. Sharing a color simulation of the completed image can facilitate discussions with neighbors and the management association.

Are there differences in construction depending on the location, such as near stations, residential areas, complexes, or industrial areas?

Chuo Ward includes various areas with different environments, such as the central urban area around Sagamihara Station, residential areas near stations like Fuchinobe and Kamimizo, older complexes, industrial complexes in Tana, Miyashita, and Koyama, and agricultural land along the Sagami River. Depending on the location, there may be differences in road width, distance from neighboring properties, pedestrian pathways, and types of buildings (mixed-use buildings, wooden apartments, condominiums, complexes, factories, warehouses, etc.), which may require ingenuity in setting up scaffolding and transporting materials. Kakeru Koumuten Co., Ltd. has its own scaffolding team that will check the site and plan the transportation route and scaffolding layout. Additionally, there are flood inundation risk areas along the Sagami and Sakai rivers, and some areas like sloped forests are designated as landslide disaster warning zones (Sagamihara City Urban Planning Master Plan). We also focus on inspecting rooftop drains, drainage areas, and the condition of waterproofing layers. The degree of deterioration varies by building, so we conduct individual diagnoses during on-site surveys.

Which method should I choose: responsibility construction method or design supervision method?

For buildings with fewer units, the burden of consulting fees tends to be heavier, so we believe that the responsibility construction method is often more suitable for small to medium-sized buildings. The design supervision method allows for comparison of construction companies under the same conditions since a third party creates the specifications; however, 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 you to compare with other companies on the same level.

How can I detect collusion in large-scale repairs?

There are three typical methods: ① Pre-selecting a contractor and having other companies submit only nominally high estimates, known as “dummy estimates,” ② A consultant contracting at an extremely low design supervision fee and receiving kickbacks from affiliated contractors, 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 meeting minutes, and including penalty clauses in contracts.

How many companies should I get estimates from?

最低3社をおすすめします。多すぎると比較しきれず、少なすぎると競争が働きません。大切なのは社数よりも「同じ土俵を作ってから比べること」です。共通の仕様書や数量表を作って同一条件で依頼し、「一式」表記を認めず内訳明細を必須にすると、金額差が範囲の違いなのか単価の違いなのかがはっきりします。

What is the difference if we own our own scaffolding?

In large-scale repair projects, temporary construction accounts for about 20% of the total cost (according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for Reiwa 3). By not outsourcing scaffolding work, we can easily control costs in this area, and our in-house scaffolding team can flexibly respond to sudden changes in the schedule or additional work. Kakeru Koumuten Co., Ltd. owns scaffolding materials for approximately 100 single-family homes and plans scaffolding on-site according to the site conditions.

Can I just have a look at the estimate while I’m in the middle of getting multiple quotes?

Of course, that’s possible. If you bring in estimates from other companies, we will check whether the items, quantities, methods, and materials are appropriate for free and provide you with an estimate under the same conditions. We welcome multiple estimates.

Can I request just emergency repairs for a leak?

Yes. As a preliminary step before large-scale repairs, we also accept requests for emergency repairs or partial repairs for leaks. We will identify the cause using thermal imaging and drones and propose the minimum necessary repairs.

Can you handle roofing or exterior wall materials that contain asbestos?

Yes, we can. We have qualified personnel, including asbestos work supervisors and investigators for buildings containing asbestos materials, who can handle everything from the legally required preliminary surveys to the cover method and removal of asbestos-containing roofing materials. The availability of subsidies for investigation and removal costs in cases of sprayed asbestos may vary by year, so please check in advance with the municipal office. We will also provide guidance from the investigation stage.

What happens if large-scale repairs are not done?

There are risks such as personal injury accidents due to falling exterior wall tiles, structural deterioration due to corrosion of rebar, leaks, and a decrease in asset value. Furthermore, for buildings subject to regular reporting under Article 12 of the Building Standards Act, investigations using full tapping and other methods are required under certain conditions, such as when more than 10 years have passed since completion or exterior wall renovations for tiled or mortar-finished walls. In the list of buildings subject to regular reporting in Sagamihara City, apartment buildings may also be included based on conditions such as the number of floors and floor area, and mixed-use buildings including stores require individual confirmation (Sagamihara City Building Examination Division Phone 042-769-8254). Even if not subject to statutory investigations, regular inspections and maintenance are essential, so please consult us if you are unsure about your judgment.

How much does large-scale repair for an apartment (about 10 units) cost?

For a two-story wooden building with 6 to 10 units, the estimate is around 2 million to 4 million yen, and for a three-story steel or RC building with 10 to 20 units, it is around 4 million to 9 million yen based on our company’s track record (including scaffolding, substrate repairs, exterior wall painting, sealing, and waterproofing). It is common to conduct repairs for apartments every 10 to 15 years. For owners, there is an increasing trend to use color simulations to change the appearance while conducting repairs, aiming to improve occupancy rates.

If you are looking for a large-scale repair contractor in Sagamihara City Chuo Ward, contact Kakeru Koumuten Co., Ltd.

Our company is based in Yokohama City and has handled many exterior wall renovations and large-scale repairs for condominiums and apartments in Chuo Ward. We are happy to assist not only with large-scale repair work but also with partial repairs and leak repairs. In urgent cases such as leaks, emergency measures may be possible, so please feel free to consult us. “I want it to last long with one renovation” “I want to keep costs down as much as possible” “I want to improve insulation performance 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 lose in terms of cost, quality, and scheduling compared to other companies, so we welcome multiple estimates!

Large-Scale Repair Work Service Area

Kakeru Koumuten Co., Ltd. accepts requests throughout Kanagawa Prefecture and Tokyo.

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