Leave the repairs and renovations of condominiums and apartments in Yamato City, Kanagawa Prefecture to Kakeru Koumuten Co., Ltd.!

Large-Scale Renovations for Condominiums, Apartments, and Buildings in Yamato City

Large-scale repair work that can be handled in Yamato City

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

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 we will propose the scope of work based on a deterioration diagnosis report with photographs.

Reasons Kakeru Koumuten is Chosen for Large-Scale Repairs in Yamato City

The reason why we can be entrusted with large-scale repairs in Yamato City is partly because “Kakeru Koumuten has a base in Kanagawa Prefecture”, but also due to “our unique approach to large-scale repair work that cannot be imitated by other companies”, which has 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 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 conducting scaffolding work with our own scaffolding team instead of outsourcing, we can cut costs related to 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 purchase materials at a lower cost! Additionally, since we always have stock available, we can provide speedy responses in emergencies!

In-house Sorting of Waste Materials

In large-scale repairs, various waste materials such as leftover paint, metal, and wood are generated. 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, you can not only have meetings but also check actual samples and colors of exterior materials. You can also perform color simulations for exterior wall painting and check heat insulation properties using a heat insulation testing machine!

2. Cost Reduction through In-House Management and Construction

One of Kakeru Koumuten’s major strengths is in-house management and construction.

From inquiry to project completion, everything is managed by Kakeru Koumuten in a consistent system, allowing for high-quality large-scale repairs at reduced costs. Additionally, one representative will handle everything from the estimate to project completion. Since the contact person does not change, such as between sales and construction management, smooth communication is possible.

We can handle everything from temporary scaffolding installation to exterior wall painting, substrate repairs, waterproofing, 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 construction industry licenses and permits for industrial waste collection and transportation! We also have nationally certified sheet metal and painting technicians, and we are confident in our construction techniques. We can also handle large-scale roofing projects for factories! We have qualified personnel for asbestos work supervisors and building material asbestos surveyors, so we can handle asbestos-containing roofing materials and conduct preliminary surveys.

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 annually, and we send out notification DM every 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 a drone! 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 or emergencies!

6. Staff Development

Our staff create various models for skill enhancement and conduct practical training. Since different sites require various processing and techniques, we regularly provide skill improvement education to ensure each staff member can respond effectively. 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 renovation work, we will not only notify residents and greet nearby residents, but also install a bulletin board at the entrance to display the construction schedule and notices! Additionally, we will thoroughly educate visitors on proper 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 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 confirm the quantity of used paint cans to ensure that the specified amount of paint is used, and we prevent construction defects by ordering paint directly from our company. 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

The simulations we create 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 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.

* In Yamato City, the entire area is designated as a landscape planning zone. Changing the color of the exterior walls may require notification. Having a color simulation screen will help facilitate explanations at community and management association meetings.

9-2 Confirm the Actual Color with a Sample Paint!

You can order samples of the paint you are considering and conduct a sample paint application on your exterior wall. By doing a sample 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 applying metal siding
・Simulation using accent materials such as cornices and louvers
・Simulation for roof painting and roof replacement work

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

Cost Estimates for Large-Scale Repairs in Yamato City

The cost of large-scale repairs varies significantly depending on the size of the building, the degree of deterioration, 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 construction performance by scale, and finally to examples of unit prices for each project.

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 collected 818 construction cases (FY 2021), the amount for large-scale repair work is concentrated at about 70% 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. Note that the amounts in this survey do not include consumption tax and common temporary construction costs, so they differ from the current total construction costs including tax.

Source: Ministry of Land, Infrastructure, Transport and Tourism “Survey on Large-Scale Renovation Work for Condominiums in FY2021” (200 companies, 818 cases) *Amounts do not include consumption tax equivalent or common temporary construction 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 “Survey on Large-Scale Renovation Work for Condominiums in FY2021” (Second survey of large-scale renovation work. Overall average is construction-related 59.0%, temporary construction 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 is not a criterion for judging the appropriateness of individual estimates.

Cost Estimates by Building Size (Scaffolding, Substrate Repairs, Exterior Wall Painting, Waterproofing, Sealing as a Set)

*The above estimates are based on Kakeru Koumuten’s construction records and may vary depending on the presence of roofing work, steel work, plumbing, etc. For condominiums, please also consider the amount calculated by multiplying the national statistics (750,000 – 1,500,000 JPY per unit) by the number of units.

Breakdown of Costs for Temporary Works, Substrate Repairs, Exterior Walls, and Waterproofing

The estimate for large-scale repairs is broadly divided into “Temporary Works,” “Substrate Repairs,” “Sealing,” “Exterior Painting,” “Waterproofing,” and “Miscellaneous Expenses.” Before comparing total amounts, please check what each item includes, how much, and at what price.

Example Unit Prices for Repair Work

*Costs and warranty periods vary based 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.” Aligning when to perform the next major repair with the lifespan of the materials is the most efficient way to make a selection.

* 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 change durability on shaded and humid surfaces.

Guidelines for Repair Reserve Funds and Options When Insufficient

According to the Ministry of Land, Infrastructure, Transport and Tourism guidelines, the estimate for repair reserve funds is shown as a monthly amount 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 on Condominiums)

In the Reiwa 5 Fiscal Year Comprehensive Survey on Condominiums, 36.6% of management associations reported that “the repair reserve funds are insufficient compared to the plan.” There are four main options when funds are insufficient.

Subsidies, Tax Systems, and Loans to Check for Large-Scale Renovations in Yamato City

In Yamato City, Kanagawa Prefecture, there are no subsidies specifically targeting large-scale renovation work. The available options can be broadly categorized into the following four types. The eligibility and application status of these systems may change even 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 9, 2026)

① Condominium Longevity Promotion Tax System (Property Tax Reduction)

If large-scale repairs (including exterior wall painting, floor waterproofing, and roof waterproofing) that contribute to the longevity of condominiums meeting certain requirements are carried out, the property tax amount for the following fiscal year will be reduced. The reduction rate is a “local special exception” established by the municipality within the national range (1/6 to 1/2, with the national reference standard being 1/3). In Yamato City, the reduction is 1/2, applicable up to an area equivalent to 100㎡ per unit.

② City and Prefectural Contact Points (Management Associations should start here)

Yamato City conducts management plan certification for condominiums (starting April 2024). According to the city’s “Condominium Management Improvement Promotion Plan” (formulated January 2024), 24% of the 18,180 condominiums in the city are over 33 years old (based on the 2018 Housing and Land Statistical Survey). While this is not a subsidy for the construction costs of major repairs, it can be used as a reference for consultations and decision-making in the preliminary stages.

Source: Yamato City “About the Apartment Management Plan Certification System”／Yamato City “Apartment Management Plan Certification System” (PDF)／Yamato City Apartment Management Optimization Promotion Plan (PDF)／Yamato City “Subsidy System for Earthquake Diagnosis Costs for Apartments”　*The city’s systems may change based on application status and remaining budget.

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

In Yamato City, this is a system certified by the city, and upon certification, you can meet one of the requirements for the Japan Housing Finance Agency’s “Flat 35” and interest rate reductions for apartment common area renovation loans, as well as the long-term durability promotion tax system (certification alone does not guarantee tax reductions). The certification criteria consist of 16 items based on national guidelines rather than the city’s own standards. Key criteria include holding general meetings at least once a year, maintaining management regulations, separate accounting for management fees and repair reserves, ensuring that arrears do not exceed 10% of the total, and “having a long-term repair plan that includes two or more large-scale repair works and is created or reviewed within 7 years, with a planning period of 30 years or more.”

*Before applying, it is necessary to obtain a pre-confirmation compliance certificate through the Apartment Management Center’s management plan certification procedure support service (pre-confirmation fee is 10,000 yen, tax included). Certification is subject to renewal every five years, and approval from the general meeting is required for the application. Please check the city’s website for application procedures.

④ National Energy Saving Support | Housing Energy Saving 2026 Campaign

Changes for Fiscal Year 2026The “Child-Rearing Green Housing Support Project” for Fiscal Year 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 Fiscal Year 7 and will not be implemented in Fiscal Year 8. 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 and Support (Subsidy applications for fiscal 2026 have ended)

* The Existing Housing Energy Efficiency Renovation Subsidy does not cover common areas of rental apartments or units where the owner does not reside.

⑥ Financing System (Housing Finance Agency Condominium Sumairu Loan)

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

Source: Housing Finance Agency “Condominium Sumai-Ru Loans” (Official)

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

Building Conditions and Repair Points in Yamato City

Yamato City covers an area of 27.09 km² (approximately 3 km east-west and 10 km north-south) and is located on the flat Sagamino Plateau at an elevation of about 30 to 90 m. The Hijikigawa River flows to the west and the Sakai River to the east, with urbanized areas accounting for about three-quarters (74.5%) of the city, most of which are residential areas. There are 18,180 condominium units in the city, of which 24% are over 33 years old (as of the 2018 Housing and Land Statistical Survey). However, this is a statistic for the entire city. The age and deterioration status of your own building will be individually confirmed through on-site surveys.

Source: Yamato City “Population and Household Numbers in Yamato City (Estimated Population)”／Yamato City Condominium Management Optimization Promotion Plan (PDF)／Yamato City “About the Condominium Management Plan Certification System”／Yamato City Basic Plan for General Waste Disposal Chapter 2 (Topography, Area, Urbanization Area)／Yamato City Reiwa 6 Fiscal Year Sewer Statistics (Area)　※Population and household numbers are estimated values based on the 2020 National Census.

Organizing Condominiums in Yamato City from a Repair Perspective

The table below summarizes only the items that can be confirmed from the city’s published materials. Individual building circumstances cannot be determined from the overall city numbers.

Four Key Factors to Consider for Large-Scale Repairs Unique to Yamato City

Rather than generalizing with “because it’s Kanagawa Prefecture, measures against salt damage are necessary,” we have organized four factors to keep in mind for large-scale repairs based on the rules and terrain of Yamato City. Since the circumstances differ for each building, individual confirmations will be made through on-site surveys.

Source: Yamato City “Landscape Creation” (Landscape Plan Notification) / Yamato City Apartment Management Optimization Promotion Plan / Yamato City “Reduction Measures for Fixed Asset Tax on Apartments” / Yamato City General Waste Disposal Basic Plan Chapter 2 / Yamato City “Landscape Creation”

Points of Discussion When Advancing Construction in Yamato City

*Kakeru Koumuten has established five bases centered around Yokohama City and will visit Yamato City.

Deterioration Symptoms and Timing That Require 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 judgment should be based on the condition of deterioration rather than just the number of years, so if you observe any of the symptoms listed below, we recommend an early on-site inspection.

Estimated Repair Cycles by Location (Ministry of Land, Infrastructure, Transport and Tourism Guidelines)

*The above are reference examples from the guidelines and are not uniform construction deadlines. Actual cycles are 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 “Survey on Large-Scale Repair 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 from several locations, and we combined clear waterproofing for the tile exterior wall with rooftop waterproofing for the renovation.

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

Customer Feedback

Flow from On-Site Survey to Completion of Construction

From inquiry to 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 necessary, so starting the process 1 to 1.5 years before the desired start date will allow 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, use drones or thermal imaging to inspect the roof, high places, and areas of water leakage. For properties in Yamato City, we will also check the road width, distance from neighboring properties, tree conditions, delivery routes, and parking.
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 using color simulations, paint samples, and trial painting. For management associations, we can assist in preparing materials for general meetings. In areas subject to landscape planning notifications or district plans, we will also explain the color considerations.
5. Notification to Residents & Neighbors We will distribute construction notifications, visit neighbors to greet them, and set up a bulletin board at the entrance (construction 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 in-house scaffold team will set up the scaffolding, followed by high-pressure washing, substrate repair, sealing, exterior wall painting, tile repair, waterproofing, and work on metal parts and accessories in that order. A supervisor will inspect each stage 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 are possible 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 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

The principle is to proceed with large-scale repairs while you continue to live in your home. However, there will be some limitations on your 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 the work begins.

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

There are many large-scale repair contractors that cover Yamato City, 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

Large-scale repair contractors often have websites that showcase their exterior renovation project achievements. If they provide detailed explanations of repair contents with photos, it offers reassurance as a reference when you actually request work.

It is also effective to use Google and review site ratings as a reference when comparing large-scale repair contractors! Be cautious if there are many negative reviews. If there are few reviews, also check their project achievements, explanation content, and management system.

Large-scale repair work involves not only the construction itself but also the potential for troubles with residents and neighboring residents. Therefore, 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, and we receive many requests for exterior renovations of apartments and condominiums.

Check for Warranty and Aftercare Services

When choosing a large-scale repair company, let’s confirm the availability of a warranty. If any issues such as leaks occur after the construction, having a leak warranty from the contractor ensures that repairs can be made free of charge, providing peace of mind! Companies that offer a warranty period are often confident in their work, making this a key criterion for selecting a contractor.

The warranty period varies by contractor and the nature of the work, but it is generally set between 1 to 10 years. Emergency repairs or partial repairs often do not come with a leak warranty. Some contractors also offer aftercare services separate from the warranty, so be sure to check for the availability of 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 support for simple repairs such as 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 obtain estimates from at least three companies and compare their estimates and reports! Even for the same scope of work, costs can vary between contractors, and warranties and aftercare services may differ as well. 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 repair and exterior wall painting,” and “confirmation of the process” to make an informed decision! If the quality 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 methods are suitable for the condition of the substrate!

Check These Points on the Estimate (Checklist)

Confirm 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.

Contractors that completely outsource to subcontractors may lack knowledge and experience, leading to proposals for repairs in irrelevant areas or meaningless 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.

Additionally, contractors that outsource may be slow to respond in the event of any trouble during construction. It is prudent to avoid having a company that has not actually met with the customer manage the construction. Kakeru Koumuten carries out 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 ask.” 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 a total of 1.63788 billion yen in 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).

※Based on the announcement by the Japan Fair Trade Commission (September 28, 2026).

Three Typical Methods

Source: Yokohama City “What is collusion in large-scale repair work for condominiums?” / 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 consultants or architects
• Document the vendor selection process in meeting minutes to ensure transparency
• Confirm the reasons for unusually low design supervision fees with the consultant
• 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

Contact Points for Third-Party Consultation

If you are unsure about reading estimates or how to proceed with vendor selection, consulting with a third party separate from the construction company can be effective. The main contact points available for management associations in Yamato City are as follows.

Source: Yamato City “About the Condominium Management Plan Certification System”／Yamato City “Condominium Management Plan Certification System” (PDF)／Condominium Management Plan Certification System Consultation Dial／Kanagawa Prefecture “Condominium Advisor Dispatch Project”

Frequently Asked Questions about Large-Scale Repairs in Yamato City

How much does large-scale repair in Yamato City cost?

For condominiums, according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for the 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, the cost for a two-story wooden apartment is estimated at 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment at 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings at 5,000,000 to 15,000,000 yen. The cost varies depending on the condition of the substrate and whether waterproofing and roofing work is needed, 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 according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey, the most common actual cycle is 13 years, with about 70% falling within 12 to 15 years. 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 the sealing, lifting of tiles, or breaks in the waterproof layer, it is advisable to carry out repairs without waiting for the cycle, as this can ultimately save costs. In Yamato City, as of the statistics from 2018, 24% of condominiums are over 33 years old, but this is an overall figure for the city. We will confirm and assess the age and condition of your building through an on-site survey.

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

For apartments, the period is approximately 3 weeks to 2 months, for small condominiums or buildings it is about 1.5 to 3 months, and for condominiums with over 50 units, it takes about 4 to 6 months. Residents can remain in their homes during the construction. However, while scaffolding is in place, there will 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 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, 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 the construction itself. 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 (from the preliminary confirmation by the condominium management center to the certification by Yamato City).

Are there any subsidies available for large-scale repairs in Yamato City?

In Yamato City and Kanagawa Prefecture, there do not appear to be any subsidies specifically for large-scale repair work on condominiums. However, if it is a condominium, you may be eligible for a reduction in fixed asset tax under the “Condominium Longevity Promotion Tax System” (50% in Yamato City) if certain conditions are met, and you can also utilize the free dispatch of condominium advisors from Kanagawa Prefecture. If the work includes windows and insulation, it may be eligible for “Advanced Window Renovation 2026” or “Future Eco Housing 2026.” The city’s subsidy for condominium seismic diagnosis costs applies to buildings that started construction before May 31, 1981, and is not a subsidy for construction costs. The application timing and applicants vary by system, so please check the eligibility conditions and application procedures for each system before contracting and starting construction.

I heard that fixed asset tax can be reduced with large-scale repairs; is that true?

It is true if the conditions are met. Under the Condominium Longevity Promotion Tax System, if a condominium that meets the requirements of being over 20 years old and having more than 10 units conducts large-scale repairs that contribute to longevity (including exterior painting, floor waterproofing, and roof waterproofing), the fixed asset tax for the building will be reduced in the following fiscal year (up to 100 square meters per unit). The reduction rate is determined by local ordinances within the national range (1/6 to 1/2), and in Yamato City, it is 1/2. This applies if all three works are completed by March 31, 2027, and a declaration must be submitted to the city’s asset tax division (phone 046-260-5237) within three months of the completion date. It cannot be combined with other reduction measures and is limited to one time per unit. For certified management plan condominiums, there are also requirements such as raising the repair reserve fund, which takes time to prepare, so it is recommended to start the process more than a year before the construction.

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

There are four main options. ① Postpone low-urgency repairs based on a deterioration diagnosis for the next time, 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 common area renovations in condominiums 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 and seismic work. Please note that postponing waterproofing and tile detachment measures often ends up being more costly, so please consult us for decisions on separation.

Can scaffolding be set up on narrow sites or buildings close to neighboring properties?
Yes, it can. The city of Yamato is primarily a flat plateau with few slopes, but there are also sites with limited road widths and buildings close to neighboring properties. Kakeru Koumuten Co., Ltd. owns its own scaffolding materials and has its own scaffolding team, allowing us to plan the delivery route and scaffolding layout after confirming the site. Since additional costs can easily arise after seeing the site, it is important to confirm the delivery route during the estimation stage.

What happens to the parking for residents during construction?
Vehicles on the side where scaffolding will be erected will need to be temporarily moved. In buildings where there is limited parking space on the premises, it may take time to secure an alternative parking location. Kakeru Koumuten Co., Ltd. will coordinate with you about the availability of nearby parking starting 2 to 3 months before construction begins.

Can I freely decide the color of the exterior walls?
In Yamato City, the entire area is designated as a landscape planning zone. Buildings are subject to notification if repairs or color changes alter more than half of the visible surface area, with conditions such as a height of over 10m or a total floor area of over 1,000㎡ also specified. In the notification, the colors used must be described using Munsell values. Additionally, there are areas with design restrictions under district planning. For confirmation, the landscape notification can be checked with the Urban Development Promotion Division (phone 046-260-5483), and district planning with the Urban Development Planning Division (phone 046-260-5443). We will also investigate this during our survey. Sharing a color simulation to visualize the completed image can facilitate discussions.

Why is the north-facing exterior wall particularly covered in moss and algae?
The north side receives less sunlight throughout the day, and when shadows from trees or neighboring buildings overlap, moisture can accumulate, making it easier for algae, moss, and mold to thrive. This is more likely to occur in locations close to trees. By thoroughly cleaning with high-pressure washing and selecting paint with anti-algae and anti-mold properties, recurrence can be minimized. Additionally, we recommend checking for blockages in roof drains and gutters caused by fallen leaves, as these often lead to puddles on the roof or leaks.

Which method should I choose: responsibility construction method or design supervision method?
The smaller the number of units, the heavier the burden of consulting fees, so for small to medium-sized buildings with fewer units, the responsibility construction method is often more suitable. The design supervision method allows for comparison of construction companies under the same conditions since a third party creates the specifications, but it incurs separate consulting fees and requires caution regarding conflicts of interest and collusion risks. Verification of price, specifications, and construction status is essential even under the responsibility construction method. 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 Pre-selecting the contractor 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.

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 have 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 fiscal year 2021 survey). 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 according to the site, even in areas with limited road width.

I’m in the middle of getting multiple estimates; can I just have a look at the estimate?

Of course, that’s possible. If you bring in estimates from other companies, we will check for free whether the items, quantities, methods, and materials are appropriate, 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 who are asbestos work supervisors and building material surveyors, and we handle everything from the legally required preliminary surveys to the cover method and removal of asbestos-containing roofing materials. Please check with the Yamato City office regarding the availability and conditions of assistance programs if sprayed asbestos is found. We will also provide guidance based on the survey results.

What happens if we don’t carry out large-scale repairs?

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, buildings subject to periodic reporting under Article 12 of the Building Standards Act require investigations through comprehensive probing, etc., under certain conditions, such as exceeding 10 years since completion or exterior wall renovations for tiles or mortar finishes. Yamato City is designated as a specific administrative agency, and the applicable uses and scales are defined in the city’s designated overview (from July 1, 2025). The classification of apartment buildings is also indicated, and the applicable conditions such as the number of floors and floor area vary by building, so please check with the Building Guidance Section of the city’s Building Guidance Division (phone 046-260-5425). 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 (scaffolding, substrate repairs, exterior wall painting, sealing, waterproofing as a whole). It is common for apartments to undergo repairs every 10 to 15 years. For owners, there is an increasing trend to change the appearance with color simulations during repairs to improve occupancy rates.

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

Our company handles many exterior wall renovations and large-scale repairs for condominiums and apartments in Yamato City. 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 a long time 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 be outdone by others in terms of cost, quality, and planning, 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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