Leave the repairs and renovations of condominiums and apartments in Kanazawa, Yokohama City to Kakeru Koumuten Co., Ltd.!

Large-Scale Renovations for Condominiums, Apartments, and Buildings in Kanazawa Ward, Yokohama

Large-scale repair work that can be handled in Kanazawa Ward, Yokohama City

Large-scale repairs are not just “exterior wall painting” or “waterproofing,” but rather a project that addresses the overall deterioration of the building 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 the above works. The extent of the work will be determined based on the results of the building diagnosis. At Kakeru Koumuten, we conduct free on-site surveys to confirm the following and compile a deterioration diagnosis report with photos, after which we will propose the scope of work.

Reasons Why Kakeru Koumuten is Chosen for Large-Scale Renovations in Kanazawa Ward, Yokohama City

The reason why we can be entrusted with large-scale repairs in Kanazawa 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 Ownership of Scaffolding Materials

We own the scaffolding materials necessary for temporary scaffolding required for large-scale repairs and can assemble the scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can 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 procure materials at a lower cost! Additionally, since we always have stock available, we can provide swift 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.

By having Kakeru Koumuten manage everything from inquiries to project completion in a consistent system, we can keep costs down and provide high-quality large-scale repairs. Additionally, one representative will handle everything from the estimate to project completion. Since the same person is responsible for sales and construction management, smooth communication is possible.

We can fully handle everything from temporary scaffolding installation to exterior wall painting, substrate repairs, waterproofing work, and tile repairs with our own team! 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 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 asbestos-containing material investigators, so we can handle and conduct preliminary investigations of asbestos-containing roofing materials.

4. Warranty and Aftercare

Most large-scale repair works, including “painting work,” “substrate repair work,” and “waterproofing work,” come with a warranty!
Aftercare maintenance is available every year, and we send out notification DM each year.

5. Flexible and Prompt Response

Our company is equipped to handle various troubles and situations in apartments and condominiums.

We can also address exterior walls and rooftops that cannot be inspected from high places using drones! During leak investigations, we can use a thermal imaging camera to help identify the cause of leaks!

We will respond according to your wishes. We also accept emergency measures for sudden leaks! We will promptly respond to urgent requests and emergencies!

6. Staff Development

Our staff create various models for skill 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 appropriately. We also educate on points to be careful about and areas to check during each stage of large-scale repair work.

7. Consideration for Residents and Neighbors

During large-scale repair 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 etiquette to minimize any inconvenience to residents and neighbors.

8. Strict Quality Control

Each stage will undergo inspection by a responsible person, along with detailed photographs of the work. We will use film thickness inspection machines and check sheets to ensure that no inspections are overlooked. During exterior wall painting and waterproofing work, we will verify the quantity of used paint cans to ensure that the specified amount of paint is used, and we will prevent construction defects by ordering paint in-house. 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!Simulations can also be done on your smartphone or computer. By simulating and then applying a two-tone color or changing the image, we hope to enhance the stylish appearance and increase occupancy rates! Of course, we can also arrange paint samples for actual color confirmation.

* In Kanazawa Ward, there is a scenic area (Tomioka Nagahama), and permission is required to change the color of the exterior walls within the area. There are also areas governed by building agreements and district plans. Having a color simulation screen will help facilitate explanations at the management association’s general meetings and neighborhood associations.

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 when metal siding is applied
・Simulation for when accent materials such as cornices and louvers are used
・Simulation for roof painting or roof replacement work

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

Cost Estimate for Major Repairs in Kanazawa Ward, Yokohama City

The cost of major repairs varies greatly depending on the size of the building, the degree of deterioration, the scope of work, and the materials used. First, refer to the national average based on public statistics, then to our company’s performance-based estimates 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 compiled 818 construction cases (FY 2021), the cost of major repairs 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. Yokohama City also indicates on its official website that the cost is approximately 1,000,000 to 1,300,000 yen per unit. Note that the amounts in this survey do not include consumption tax and common temporary construction costs, so the conditions differ from the current total construction cost including tax.

Source: Ministry of Land, Infrastructure, Transport and Tourism “Survey on Large-Scale Renovation Work for Condominiums in FY2021” (200 companies, 818 cases) / Yokohama City “Market Prices for Large-Scale Renovation Costs and How to Address Shortfalls in Repair Reserve Funds” *Amounts do not include consumption tax 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 it includes equipment-related work, exterior works, and others. This is an average value and is not a criterion for judging the appropriateness of individual estimates.

Cost Estimates by Building Size (Scaffolding, Substrate Repair, Exterior Painting, Waterproofing, Sealing)

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

Breakdown of Costs for Temporary Works, Substrate Repair, Exterior, and Waterproofing

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

Examples of Unit Prices for Repair Work

*Costs and warranty periods vary based 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 of charge.

Select Paint and Waterproofing Grades Based on “Years Until Next Repair”

“Good paint does not equal the right choice.” The best way to choose is to align when the next major repair will be with the lifespan of the materials, minimizing waste.

* The estimated lifespan is a general guideline and may vary depending on sunlight, location, and substrate condition. For buildings close to the sea, where they are exposed to sea breezes, choosing high-weather-resistant paints and specifications that include rust prevention for metal parts after washing off salt will change durability.

Guidelines for Repair Reserve Funds and Options When Insufficient

According to the Ministry of Land, Infrastructure, Transport and Tourism guidelines, the guideline for repair reserve funds is indicated 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 for Repair Reserve Funds for Condominiums” (Reiwa 6 June Revision – PDF) / National average is 13,378 JPY per unit per month (Reiwa 5 Fiscal Year Comprehensive Survey of Condominiums)

In the Reiwa 5 Fiscal Year Comprehensive Survey of Condominiums, 36.6% of management associations responded that “the repair reserve fund is insufficient compared to the plan.” There are four main options when there is a shortfall.

Subsidies, Tax Systems, and Loans to Confirm for Large-Scale Renovations in Kanazawa Ward, Yokohama City

Both Yokohama City and Kanagawa Prefecture do not have subsidies specifically for large-scale renovation work. The available options can be broadly categorized into the following four types. The eligibility and application status of the systems may change during the fiscal year, so please be sure to confirm with our company or each contact point before signing a contract or starting work. (As of October 7, 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 certain qualifying condominiums are carried out, the fixed property tax amount for the following year will be reduced by half (up to 100㎡ per unit; urban planning tax is not included).

② Support for Apartment Management in Yokohama City (For Management Associations, Start Here)

The support system in Yokohama City is mostly based on registration in the “Yokohama City Apartment Registration System” (free). Management associations that are not yet registered should start here.

Source: Yokohama City “Support and Subsidy System List by Concerns for Condominium Management Associations” / Long-term Repair Plan Creation Promotion Model Project / Condominium Advisor Dispatch / Seismic Reinforcement Subsidy for Specific Buildings / Yokohama Condominium Portal

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

This is a system certified by Yokohama City. Upon certification, the loan interest rate from the Japan Housing Finance Agency is reduced by 0.2% per year, preferential interest rates for Flat 35, and it meets one of the requirements for the Long-lasting Housing Promotion Tax System (certification alone does not guarantee tax reduction). The main criteria include holding general meetings at least once a year, establishing management regulations, separate accounting for management fees and repair reserves, ensuring that the amount in arrears is within 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 seven years, with a planning period of 30 years or more.”

*Fees include a system usage fee of 10,000 yen + a municipal application fee of 3,900 yen, among others. It takes 2 to 3 months from application to certification. The certification is valid for 5 years.

④ National Energy Conservation Support | Housing Energy Conservation 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 create financial plans based on outdated information.

Mirai Eco Housing 2026 Project

Advanced Window Renovation 2026 Project

⑤ Kanagawa Prefecture Subsidies (Applications for FY2026 have ended)

* The Existing Housing Energy Efficiency 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 Kanazawa Ward, Yokohama City

Kanazawa Ward, Yokohama City, is located at the southern tip of Yokohama City, facing Tokyo Bay to the east. The majority of the ward consists of hilly terrain with elevations around 100 meters. In the coastal area, there are regions developed through the Kanazawa Reclamation Project, which began in 1971 and was completed in 1988, featuring industrial parks and seaside parks. In the hilly areas, there are residential areas such as Nokeidai, Tomioka, and Nishishiba, where district plans and building agreements have been established. The presence of residential areas in hilly regions, reclaimed coastal areas, and urban areas around train stations within the same ward serves as a starting point for considering large-scale repairs in Kanazawa Ward.

Source: Yokohama City “Estimated Population and Household Numbers” (Population News)／Kanazawa Ward Statistical Overview／Kanazawa Ward “Location and Topography”／Yokohama City “District Plan (Kanazawa Ward)”／Yokohama City “List of Scenic Areas”／Kanazawa Ward “Historical Timeline”

Let’s also check the overall numbers for housing in the ward. According to the 2020 National Census, the proportion of collective housing in Kanazawa Ward is 56.2%, the proportion of single-family homes is 41.1%, and the homeownership rate is 66.7% (Kanazawa Ward Statistical Overview). While collective housing exceeds half, this is an overall figure for the ward and does not indicate the condition of individual buildings.

Buildings in Kanazawa Ward are divided into “four faces”

The buildings in Kanazawa Ward reflect the history of development, which has resulted in distinct characteristics for each location. The type of major repairs that will be required for your building during the next large-scale renovation will vary depending on its location. Please note that the history of rebuilding or large-scale renovations differs for each building, so the age of the building should be viewed as a guideline.

Source: Kanazawa Ward “Historical Timeline” (Completion of Hiragata Bay landfill and establishment of Yanagimachi in 1966, start of Kanazawa Coastal Landfill Project in 1971 and completion in 1988, year of town incorporation) / Yokohama City “Building Agreements (Kanazawa Ward)” / Yokohama City “District Plans (Kanazawa Ward)”

Four Factors Unique to Kanazawa Ward That Damage Buildings

The content of large-scale repairs varies depending on the location of the building. When investigating buildings in Kanazawa Ward, we particularly check the following four factors. While I will discuss based on overall trends in the ward, the actual conditions differ from building to building, so we will always confirm on-site.

Source: Kanazawa Ward “Location and Topography” / Yokohama City “Tsunami Hazard Map”・Kanazawa Ward “Disaster Prevention Plan and Hazard Maps” / Yokohama City “Kanazawa Coastal Area Industrial Revitalization Plan” / Yokohama City “List of Scenic Areas”・“Permits in Scenic Areas” / “Building Agreements (Kanazawa Ward)”

Key Points to Consider When Advancing Construction in Kanazawa Ward

* Kakeru Koumuten has five locations in Yokohama City, including a showroom and material storage, and we handle consultations throughout Kanazawa Ward, including Kanazawa Hakkei, Kanazawa Bunko, Nokeidai, Tomioka, Mutsuura, and Kamariya.

Signs of Deterioration Requiring Major Repairs and Timing

Generally, major repairs are considered to be on a 12 to 15-year cycle. 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 repeated repairs. However, the actual judgment should be based on the condition of deterioration rather than just the number of years, so if you observe symptoms like those below, we recommend an early on-site survey.

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 will be set according to the building’s specifications, location conditions, and deterioration status.

Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines for Creating Long-Term Repair Plans” (Revised June 2024, PDF) / Ministry of Land, Infrastructure, Transport and Tourism “Survey on Actual Conditions of 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. The building had leaks occurring from several locations, and it was renovated by combining clear waterproofing for the tile exterior wall and waterproofing for the rooftop.

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

Customer Feedback

Flow from On-Site Investigation 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 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, just presenting them is fine.
2. On-site Investigation & 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 Kanazawa Ward, we will also check for rust on metal parts of buildings near the sea, the condition of slopes and retaining walls, as well as the delivery route and parking.
3. Investigation 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 scenic district regulations, district plans, and building agreements, we will also explain the procedures and considerations for color choices.
5. Notification to Residents & Neighbors We will distribute construction notices, conduct greetings to neighbors, and set up a bulletin board at the entrance (with a schedule and laundry information). If temporary relocation of parking is necessary, adjustments will be made at this stage.
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 supervisor 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

Equally 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 requires approval before the contract.

How Will Life Be During Construction? Impact on Residents

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

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

There are many large-scale repair contractors that cover Kanazawa Ward in Yokohama 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 gives you peace of mind as a reference when you actually request work.

Using Google and review sites to evaluate large-scale repair contractors can also be effective when comparing them! Be cautious if there are many negative reviews. If there are few reviews, also check their construction 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 nearby neighbors. 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 presence 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 at no cost, providing peace of mind! A company that offers a warranty is a sign of confidence in their work, which can serve as a criterion for selecting a contractor.

Warranty periods vary by contractor and the nature of the work, but it is common to have a range from 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 presence 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 simple repairs such as partial sealing at no charge.

Obtain Estimates from Multiple Contractors (at least 3 companies)

When requesting large-scale repairs, let’s obtain estimates from multiple contractors. It is important to obtain estimates from at least 3 companies and compare their estimates and reports! Even for the same scope of work, costs can vary by contractor, 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 repair and exterior wall painting,” and “confirmation of the process” in detail! If the quality of auxiliary materials is low or if processes are skipped, costs can be reduced, so avoid making decisions based solely on price. Especially since substrate repair work can be hard to discern from the exterior, be sure to check whether the repair method is suitable for the condition of the substrate!

Check This 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 state and customer preferences.

Contractors that completely outsource to subcontractors may lack knowledge and experience, leading to proposals for repairs in irrelevant areas or unnecessary work. If you investigate and then request a subcontractor, it may incur additional time and costs. By having knowledge and experience and managing in-house, responsible construction that reduces costs becomes possible.

Additionally, contractors that outsource may also be slow to respond in case of any troubles during construction. It is safer to avoid companies that do not have direct meetings with customers managing the construction. Kakeru Koumuten performs everything from temporary scaffolding installation to exterior wall painting and waterproofing work in-house, managed by knowledgeable and experienced personnel!

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 concern. The Ministry of Land, Infrastructure, Transport and Tourism issued warnings and notifications to management associations in January 2017 and April 2023, and on September 28, 2026, the Japan Fair Trade Commission announced that it had issued exclusion orders to 38 companies and payment orders for a total of 1.63788 billion yen to 37 companies regarding large-scale renovation work commissioned by condominium management associations to design consulting firms in the Kanto region (two design consulting firms were also subject to exclusion orders).

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

Three Typical Schemes

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 professionals or architects
• Document the vendor selection process in meeting minutes to ensure transparency
• Confirm the reasons for unusually low consulting fees
• Include a penalty clause in the contract for cases of collusion
• Avoid concentrating information with a single consultant and have the management association verify specifications as well

New System in Yokohama City Bid Agency Service for Large-Scale Repair Work

In response to this issue, in October 2025, Yokohama City and the Yokohama Housing Supply Corporation established the “Bid Agency Service for Large-Scale Repair Work.” This system separates the selection of design and construction companies, with the corporation acting as a third party to conduct conditional general competitive bidding. The estimated price will not be disclosed, and the process will follow methods similar to public works.

Source: Yokohama City Press Release (October 16, 2025) / Yokohama Housing Supply Corporation

Frequently Asked Questions about Large-Scale Repairs in Kanazawa Ward, Yokohama

How much does large-scale repair in Kanazawa Ward, Yokohama 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. Yokohama City also indicates “approximately 1,000,000 to 1,300,000 yen per unit.” Based on our company’s construction records, the estimate for a two-story wooden apartment is 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment is 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings is 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 12 to 15 years. However, the decision should be based on the condition of deterioration rather than just the number of years. If signs of deterioration such as sealing degradation, tile lifting, or waterproof layer breakage are observed, it is advisable to carry out repairs without waiting for the cycle, as this can ultimately reduce costs. In older buildings, the proportion of tile repairs and steel part replacements tends to increase in the second and third rounds of repairs.

How long does the construction period take? 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 more than 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 may be restrictions on drying laundry outside and opening windows, so we take thorough measures to minimize the impact on daily life, such as distributing notifications before construction, 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 establishing a repair committee, conducting building diagnostics, selecting contractors, and passing resolutions at general meetings, followed by another 3 to 6 months for construction. Overall, it is advisable to plan for about 2 years to proceed comfortably. If you are using subsidies or tax incentives, please also factor in the time required to obtain management plan certification (2 to 3 months from application to certification).

Are there any subsidies available for large-scale repairs in Kanazawa Ward, Yokohama?

Neither Yokohama City nor Kanagawa Prefecture offers subsidies specifically for large-scale repair work. However, for condominium owners, if certain conditions are met, you can benefit from a 50% reduction in fixed property tax under the “Condominium Longevity Promotion Tax System,” subsidies from Yokohama City for deterioration diagnosis and long-term repair planning (50% up to 200,000 yen), and subsidies for barrier-free renovations in common areas (one-third up to 300,000 yen). If the work includes windows and insulation, it may be eligible for “Advanced Window Renovation 2026” or “Mirai Eco Housing 2026.” The application timing and applicants vary by program, so please check the eligibility conditions and application procedures for each program before contracting or starting work.

I heard that fixed property tax can be reduced through 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 criteria of being over 20 years old and having more than 10 units undergoes large-scale repairs (including exterior painting, floor waterproofing, and roof waterproofing), the fixed property tax for the following year 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 Kanazawa Ward Office within three months of completion. For certified management plan condominiums, there are additional requirements such as raising the repair reserve fund, so it is recommended to start preparations more than a year in advance.

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

Yes. 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 association 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 apartment buildings starting May 29, 2026 (the application process is handled by registered contractors). Please be careful not to base your financial plans on outdated information.

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

There are mainly four options: ① Postpone low-urgency work based on deterioration diagnosis to 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 loans from the Japan Housing Finance Agency. The agency’s condominium common area renovation loan does not require collateral, and by obtaining management plan certification and implementing energy-saving and seismic work, the interest rate can be reduced by up to 0.6% per year. Please note that postponing waterproofing and tile peeling measures often ends up being more expensive, so please consult us for a decision on separation.

Can scaffolding be set up on buildings located on sloped or uneven terrain?

Yes, it can. Kanazawa Ward is largely a hilly area with significant elevation changes (generally a terrain with mountains around 100m), and there are buildings on sloped or terraced sites in residential areas and housing complexes. Kakeru Koumuten Co., Ltd. owns its own scaffolding materials and has its own scaffolding team, allowing us to plan support and layout of the boards after confirming the site. This is a part where additional costs can easily arise after seeing the site, so it is important to check the delivery route during the estimation stage. We also check the deterioration of retaining walls and slopes and consult on whether they are included in the long-term repair plan.

What will happen to the residents’ parking during construction?

Vehicles on the side where scaffolding is to be erected will need to be temporarily moved. In buildings with parking lots within the complex or site, securing a relocation spot may take time depending on the number and arrangement of vehicles. Kakeru Koumuten Co., Ltd. will coordinate with you, including checking the availability of nearby coin parking and monthly parking lots, starting 2 to 3 months before construction begins.

Can the color of the exterior walls be freely decided?

This depends on the regulations affecting the building’s site. In Kanazawa Ward, there is the Yokohama City scenic area “Tomioka Nagahama,” where permission is required for changes in exterior color. Additionally, there are nine district plans within the ward, and multiple areas have building agreements, which differ by district (some agreements do not specify colors). You can check what regulations apply to your site at the Yokohama City scenic area office or the building agreement office. Our company will also investigate this during the survey, share the completion image through color simulation, and assist in building consensus with the management association and neighbors.

Do buildings close to the sea need salt damage measures?

Kanazawa Ward faces Tokyo Bay to the east, and the coastal area is a reclaimed zone. In buildings close to the sea, salt carried by sea breezes can adhere to exterior walls, metal parts, and fittings, accelerating rust progression. However, the extent of the impact varies depending on the distance from the sea, direction, and height of the building, so it cannot be said that it is universally necessary. We will check the progression of rust on metal parts and fittings during the on-site survey, and after thoroughly washing off the salt with high-pressure washing, we will propose specifications that include highly weather-resistant paint and rust prevention measures.

Which should I choose, the responsibility construction method or the design supervision method?

In 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. Verification of price, specifications, and construction status is essential even in the responsibility construction method. 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 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, ③ Adding a portion of the contract amount as a back margin to the construction cost. Countermeasures include obtaining independent estimates, consulting a neutral third party, documenting the selection process in minutes, and including penalty clauses in contracts. In October 2025, Yokohama City and the Yokohama City Housing Supply Corporation will establish a “Large-Scale Repair Work Bidding Agency Service.”

How many companies should I get estimates from?

We recommend at least three companies. If there are too many, it becomes difficult to compare; if there are too few, competition does not occur. What is important is not the number of companies, but “creating the same level of comparison.” By creating a common specification sheet and quantity table and requesting under the same conditions, and making detailed breakdowns mandatory instead of accepting “one set” notation, it becomes clear whether the price difference is due to differences in scope or unit prices.

What is the difference if you own your own scaffolding?

Among the costs of large-scale repair work, temporary construction accounts for about 20% (according to the Ministry of Land, Infrastructure, Transport and Tourism’s fiscal year 2021 survey). By not outsourcing scaffold work, we can easily control costs in this area, and our in-house scaffold team can flexibly respond to sudden changes in the schedule or additional work. Kakeru Koumuten Co., Ltd. owns scaffold materials for approximately 100 detached houses and plans according to the site, even on slopes or uneven terrain.

Can I just have a look at the estimate while I’m in the process of comparing quotes?

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 comparisons of estimates.

Can I request just an emergency repair 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 certified as asbestos work supervisors and building material inspectors for asbestos-containing materials. We handle everything from the legally required preliminary surveys to the roof overlay method and removal of asbestos-containing roofing materials. If there is sprayed asbestos, you may be eligible for free surveys and up to two-thirds (maximum 3 million yen) subsidies for removal and other construction costs through Yokohama City’s countermeasures project, so we will provide information on that as well.

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

There are risks such as personal injury from falling exterior wall tiles, structural deterioration due to corrosion of rebar, leaks, and a decrease in asset value. Furthermore, for buildings subject to periodic reporting under Article 12 of the Building Standards Act, investigations through full probing are required under certain conditions, such as when more than 10 years have passed since completion or exterior wall renovations for tiles or mortar-finished walls. In Yokohama City, buildings that are only apartments are not designated for periodic reporting, but mixed-use buildings that include stores require individual confirmation. Even if not subject to statutory surveys, 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 wooden two-story buildings with 6 to 10 units, the estimate is around 2 million to 4 million yen, and for three-story steel or RC buildings 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 carry out repairs for apartments 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 Kanazawa Ward, Yokohama City, contact Kakeru Koumuten

Our company handles many exterior wall renovations and large-scale repairs for condominiums and apartments in Kanazawa Ward, Yokohama 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 long with one renovation” “I want to keep costs down as much as possible” “I want to improve insulation performance because the interior is hot” We will propose the best solutions for your specific requests and future repair plans.

From temporary scaffold 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 comparisons of estimates!

Areas Covered for Large-Scale Repair Work

Kakeru Koumuten accepts requests throughout Kanagawa Prefecture and Tokyo Metropolis.

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