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

Large-Scale Repairs for Condominiums, Apartments, and Buildings in Nakahara Ward, Kawasaki City

Large-scale repair work that can be handled in Nakahara Ward, Kawasaki City

Large-scale repairs are not just “exterior painting” or “waterproofing,” but rather a comprehensive repair of the entire 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 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 details below, compile them into a deterioration diagnosis report with photos, and then propose the scope of work.

Reasons Why Kakeru Koumuten is Chosen for Large-Scale Renovations in Nakahara Ward, Kawasaki City

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

1. Equipment Specialized for Exterior Renovations

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

In-house Scaffolding Materials

We own the scaffolding materials necessary for temporary scaffolding required for large-scale repairs and can assemble the scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can cut costs 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, we always have stock available, so we can provide swift responses in emergencies!

In-house Waste Sorting

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

Showroom Dedicated to Exterior Renovations

In the showroom, not only can you have meetings, but you can also check actual samples and colors of exterior materials. Color simulations for exterior wall painting and heat resistance tests using a heat resistance testing machine are also available!

2. Cost Reduction through In-House Management and Construction

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

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 same person is responsible for sales and construction management, smooth communication is possible.

We can handle everything from temporary scaffolding installation to exterior wall painting, substrate repairs, waterproofing work, and tile repairs with complete in-house construction! Those with specialized knowledge and experience will conduct inspections and actual construction for each process!

3. Various Permits and Skilled Workers

We have obtained construction business licenses and permits for industrial waste collection and transportation! We also have nationally certified sheet metal and painting skilled workers on staff, and we are confident in our construction techniques. We can also handle large-scale roofing work for factories! Qualified personnel for asbestos work supervisors and building material asbestos surveys are also on staff, allowing us to handle asbestos-containing roofing materials and conduct preliminary surveys.

4. Warranty and Aftercare

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

5. Flexible and Prompt Response

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

We can also address exterior walls and rooftops that cannot be checked from high places using 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!

6. Staff Development

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

7. Consideration for Residents and Neighbors

During large-scale repair work, we not only notify residents and greet neighbors, but we also set up bulletin boards in entrances to display project schedules and notices! Additionally, we thoroughly educate entrants on manners to minimize inconvenience to residents and neighbors.

8. Strict Quality Control

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

9. Exterior Painting Color Simulation

9-1 Self-Color Simulation

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

*In Nakahara Ward, there are district planning areas (8 districts) and specific areas for landscape planning (Musashi Kosugi area, Shinkawasaki area) as well as Tamagawa scenic areas (parts of Todoroki and Kosugi Jinya Town 2-chome). When changing the color of the exterior walls, permission or notification may be required. There may also be areas with building agreements. Having a color simulation screen will help facilitate explanations at management association meetings and neighborhood associations.

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

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

9-3 Exterior renovation simulation

Exterior simulations for apartments and condominiums are also possible!
・Exterior wall color simulation (two-tone colors are also possible)
・Simulation for when metal siding is applied
・Simulation using accent materials such as cornices and louvers
・Simulation for roof painting or roof replacement work

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

Cost Estimates for Major Repairs in Nakahara Ward, Kawasaki City

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

The national average for condominiums is 750,000 to 1,500,000 yen per unit

According to a survey conducted by the Ministry of Land, Infrastructure, Transport and Tourism, which compiled 818 construction cases (FY 2021), approximately 70% of the costs for major repairs are concentrated in the range of 750,000 to 1,500,000 yen per unit, with the most common price range being 1,000,000 to 1,250,000 yen. Note that this survey’s figures do not include consumption tax and common temporary construction costs, so they differ from the current total project costs including tax.

Source: Ministry of Land, Infrastructure, Transport and Tourism “FY 2021 Survey on Major Repair Work for Condominiums” (200 companies, 818 cases)　*The 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 “Fiscal Year 2021 Survey on Large-Scale Repair Work for Condominiums” (Second survey of large-scale repair work. The overall average is construction work 59.0%, temporary work 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 not a criterion for judging the appropriateness of individual estimates.

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

*The above is an estimate based on Kakeru Koumuten’s construction performance and may vary depending on the presence of roofing work, steel work, drainage pipes, etc. For condominiums, please also consider the amount obtained by multiplying the above national statistics (750,000 – 1,500,000 JPY per unit) by the number of units as a guideline.

Cost Breakdown for Temporary Works, Substrate Repairs, Exterior Walls, and Waterproofing

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

Examples of Unit Prices for Repair Work

*Costs and warranty periods vary depending on shape, quantity, substrate condition, and type of materials. For a detailed estimate, please feel free to contact us. Estimates are completely free.

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

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

* The estimated lifespan is a general guideline and may vary depending on sunlight, location, and substrate condition. For areas exposed to strong rain, wind, and sunlight, choosing high-weather-resistant paint and specifications that include rust prevention for metal parts after cleaning dirt will improve durability.

Guideline for Repair Reserve Fund and Options When Insufficient

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

Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines 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 comprehensive survey for the fiscal year Reiwa 5, 36.6% of management associations responded that “the repair reserve fund is insufficient compared to the plan.” There are four main options if there is a shortfall.

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

Both Kawasaki City and Kanagawa Prefecture do not have subsidies specifically for large-scale renovation work itself (Kawasaki City has indicated that there are no subsidies for renovation work aimed at exterior wall painting or roof repairs). The following four types can be utilized. 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 contracting or starting work.(As of October 8, 2026)

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

If large-scale repairs (all three types: exterior wall painting, floor waterproofing, and roof waterproofing) that contribute to the longevity of condominiums meeting certain requirements are carried out, the fixed property tax amount for the following year will be reduced by half (up to the equivalent of 100㎡ per unit; urban planning tax is not included).

② Support for Apartment Management in Kawasaki City: Subsidies by Purpose (For Management Associations, Start Here)

Kawasaki City has a “Kawasaki City Apartment Management Association Registration and Support System” (Free Registration). By registering, you will receive the “Apartment Newsletter,” and the number of advisor dispatches will also increase. Management associations that have not yet registered, this is your starting point.

Source: Kawasaki City “Support System for Condominium Management Associations” ／ Kawasaki City Housing Subsidy System Information ／ Sprayed Asbestos Subsidy System ／ EV Charging Infrastructure Subsidy (for Multi-Family Housing) ／ Reiwa 8 Fiscal Year Solar Power Generation Equipment Installation Subsidy　*The status of applications and upper limits for barrier-free and seismic grants are not listed on the city’s page.

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

This is a system certified by Kawasaki City. Once certified, you may receive interest rate benefits for the “Condominium Common Area Renovation Loan” from the Japan Housing Finance Agency and Flat 35 (Maintenance Type), and it is also one of the requirements for the Long-Life Promotion Tax System (certification alone does not guarantee tax reductions). The main criteria include holding a general meeting at least once a year, maintaining management regulations, separate accounting for management fees and repair reserves, having overdue amounts of three months or more within 10% of the total, and “having a long-term repair plan that includes two or more large-scale repair works within the remaining period and for a planning period of 30 years, created or reviewed within the last 7 years”, as well as being registered in the city’s registration and support system.

*The registration fee and certification application fee for Kawasaki City are free (additional costs may apply for prior confirmation). The validity period of the certification is 5 years. Applications proceed in the order of resolution at the general meeting, prior confirmation through the “Management Plan Certification Procedure Support Service,” and city registration.

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 establish 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 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 Sumairu Loan” (Official)

Cases where fire insurance can be used and cases where it should not be used

Building conditions and repair points in Nakahara Ward, Kawasaki City

Nakahara Ward, Kawasaki City, is located almost in the center of Kawasaki City, with most of the ward being flat land along the Tama River, while the southwestern area, the Ida district, features hilly terrain with remaining greenery. The ward’s name is believed to originate from the temporary palace in Kosugi, which served as a relay point on the Nakahara Highway connecting Edo and Nakahara Palace (in Hiratsuka City). The Maruko-Tamagawa section of the Tokyo Yokohama Electric Railway (now the Tokyu Toyoko Line) opened in 1926, followed by the Kawasaki-Noborito section of the Nambu Railway (now the JR Nambu Line) in 1927, and the Maruko Bridge over the Tama River in 1935. Subsequently, urbanization progressed as a suburban residential area for Tokyo, Yokohama, and southern Kawasaki, leading to the formation of commercial areas and the establishment of production sectors centered around companies with headquarters in the city center, shaping the current structure of the town. The ward was established when Kawasaki City transitioned to a designated city in 1972, and it was reorganized into seven wards in 1982. In recent years, large-scale redevelopment has been progressing around Musashi-Kosugi Station, which opened in March 2010 on the JR Yokosuka Line. The different characteristics of the redevelopment area around Musashi-Kosugi Station, residential areas and shopping streets along the Tokyu Toyoko Line and Nambu Line, lowlands along the Tama River, and the hilly terrain of Ida are the starting points for considering large-scale repairs in Nakahara Ward.

Source: Kawasaki City “Population Report” (Estimated as of September 1, 2026)／Kawasaki City “Population by Age” (As of October 1, 2020)／Nakahara Ward “Overview of Nakahara Ward”／Kawasaki City “Overview, Situation, and Characteristics of Nakahara Ward”／Kawasaki City “District Planning List” ※The rankings are based on the numerical values in the table, with the elderly population ranked from the highest districts, and others ranked from the most populous districts.

Let’s also check the composition of generations and households. The proportion of the elderly population (aged 65 and over) in Nakahara Ward is 15.3% (2020), which is the lowest among the seven wards in Kawasaki City, while the proportion of the working-age population (aged 15 to 64) is 71.8%, the highest in the ward. The youth population (under 15 years old) is 12.9%. Calculating from the population and number of households, there are approximately 1.9 people per household. These figures represent the entire ward and do not indicate the situation of individual building occupants. According to the ward’s 2008 data, there has been an influx of population, and it is gradually changing into an urban residential area centered around apartment buildings, with a high ratio of young generations in their 20s and 30s and single-person households, indicating that the composition of generations varies by location within the same ward.

Buildings in Nakahara Ward are divided into “four faces”

The buildings in Nakahara Ward reflect the history of railway openings, urbanization, and recent redevelopment, which have become characteristics of each location. The major repairs that will be required in the next large-scale renovation will vary depending on where your building is located. Please note that the history of rebuilding and large-scale renovations differs for each building, so the age of the building should be viewed as a guideline.

Source: Nakahara Ward “Overview of Nakahara Ward” (Updated November 28, 2024. Birth of the ward in 1972, opening of Musashi-Kosugi Station on the Yokosuka Line in 2010, Ida area) / Kawasaki City “Nakahara Ward Overview, Situation, Characteristics” (Published in 2008. Origin of the ward name, Marukobashi, urbanization as a suburban residential area) / Nakahara Ward “History of Nakahara Ward” (Year of railway opening) / Kawasaki City “Current Situation and Main Issues of Nakahara Ward” (Published in 2008. Urban residential area centered on apartment buildings, shopping streets, bicycles and parking lots) / Kawasaki City “Current Situation and Issues of Nakahara Ward” (PDF, Data as of October 1, Reiwa 3) (Redevelopment, high-rise condominiums, flooding damage from the Typhoon in Reiwa 1, division in 1982) / Kawasaki City “Flood Hazard Map” / Kawasaki City “District Planning List” / Kawasaki City “Specific Areas of Landscape Planning” / Kawasaki City “Scenic Areas” *Descriptions in the ward’s materials are from around 2008 and Reiwa 3, and may differ from the current situation.

Four Unique Factors in Nakahara Ward That Damage Buildings

The contents of large-scale repairs vary depending on the location of the building. When investigating buildings in Nakahara Ward, the following four factors are particularly important to confirm. I will discuss based on the overall trends in the ward, but the actual conditions differ for each building, so be sure to confirm on-site.

Source: Kawasaki City “Flood Hazard Map”・“Internal Water Hazard Map”／Kawasaki City Waterworks Bureau “Verification of Flooding in Areas Around Drainage Pipes Due to Typhoon in Eastern Japan in Reiwa Year 1”／Kawasaki City “Landslide Hazard Map”／Kawasaki City “Current Situation and Main Issues in Nakahara Ward” (Published in 2008)／Kawasaki City “Current Situation and Issues in Nakahara Ward” (PDF)／Kawasaki City “District Planning List”／Kawasaki City “Specific Areas of Landscape Planning”／Kawasaki City “Scenic Areas”／Kawasaki City “Building Agreements” *Descriptions in district materials are from around 2008 and Reiwa Year 3.

Key Issues to Address in Nakahara Ward During Construction

* Kakeru Koumuten has five locations in Yokohama, including a showroom and material storage, and we respond to inquiries throughout Nakahara Ward, including Kosugi, Shin-Maruko, Kizuki, Shinjo, Shimonumabe, and Ida.

Signs of Deterioration Requiring Major Repairs and Timing

Generally, major 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 determination is based on the condition of deterioration rather than the number of years, so if you observe symptoms like those listed below, we recommend an early on-site investigation.

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 specifications, location conditions, and deterioration status of the building.

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. The building had leaks occurring from several locations, and we combined clear waterproofing for the tile exterior wall with waterproofing for the roof for the renovation.

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

Customer Feedback

Flow from On-Site Investigation to Completion of Construction

From 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, it’s fine to just present those.
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 rooftop, high places, and leak areas using drones or thermal imaging. For properties in Nakahara Ward, we will also check for rust on iron parts, potential flooding, internal water issues, and landslide risks, as well as high-altitude work for large buildings, access routes, and parking.
3. Submission of Investigation Report & Estimate We will provide a deterioration diagnosis report with photos and an estimate detailing quantities, methods, and materials for each work item. Multiple 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 district planning, landscape planning, scenic areas, and building agreements, we will also explain the procedures and color considerations.
5. Notification to Residents & Neighbors We will distribute construction notifications, 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, 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 and tile repair → waterproofing → iron parts and 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 finished work 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 out annual DM notifications, and annual inspections are possible. 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 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

Large-scale repairs are principally carried out while residents remain in their homes. However, there will be restrictions on daily life while scaffolding is in place. Most troubles can be prevented by providing prior notice, so Kakeru Koumuten Co., Ltd. thoroughly explains and posts information before construction begins.

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

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

Extensive Experience in Large-Scale Repairs

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

Using ratings from Google and review sites can be effective when comparing large-scale repair contractors!Be cautious if there are many negative reviews. If there are few reviews, also check the construction track record, the content of explanations, and the management system.

Large-scale repair work involves not only the construction itself but also potential troubles with residents and nearby neighbors. Therefore, it is necessary to report the progress of the work and laundry information on bulletin boards to prevent troubles before they occur. Kakeru Koumuten Co., Ltd. specializes in exterior work, and we receive many requests for exterior renovations of apartments and condominiums.

Check for warranties and aftercare services

When choosing a large-scale repair company, make sure to check forwarranties. If any issues such as leaks occur after 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 be a criterion for selecting a contractor.

Warranty periods vary by contractor and type of work, but typically range from 1 to 10 years. Emergency repairs or partial fixes often do not come with a leak warranty. Some contractors also offer aftercare services separate from warranties, so be sure to checkif there are warranties or aftercare services available.

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 like partial sealing.

Obtain estimates from multiple contractors (at least 3 companies)

When requesting large-scale repairs, be sure to obtain estimates from multiple contractors. It is important to get estimates from at least 3 companies and compare their estimates and reports! Even for the same type of work, costs may vary between contractors, and warranties and aftercare services may differ as well. Additionally, obtaining multiple estimates makes price negotiations easier.

When comparing estimates, do not focus solely on costs, but also carefully compare“the items in the estimate,” “the methods and materials for substrate repair and exterior wall painting,” and “the confirmation of processes.” Avoid making decisions based only on cost, as using lower-grade materials or skipping processes can reduce costs. Particularly, substrate repair work can be difficult to assess from appearance alone, so ensure that the repair method is appropriate for the condition of the substrate!

Check these points in the estimate (checklist)

Check if it is managed in-house

Large-scale repair work includes various tasks such as “substrate repair work,” “exterior wall painting,” “waterproofing work,” and “pipe replacement,” and the plan content will change based on the actual deterioration condition and customer preferences.

Contractors that completely outsource to subcontractors lack knowledge and experience, which may lead to proposals for repairs in irrelevant areas or unnecessary work. If you request a subcontractor after investigation, it may incur additional time and costs. By having knowledge and experience and managing in-house, responsible construction can be carried out at a reduced cost.

Furthermore, contractors that outsource may also be slow to respond in case of any troubles during construction. It is advisable to avoid having a company that has not actually met with the customer manage the construction. Kakeru Koumuten performs everything from temporary scaffolding setup to exterior wall painting and waterproofing work in-house, 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 hire.” The main ordering methods are as follows.

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 in the Kanto region to design consulting firms (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 Methods

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

Self-Defense Measures for Management Associations

• Obtain independent estimates from multiple companies
• Consult with neutral third parties such as condominium management professionals or architects
• Document the contractor selection process in meeting minutes to ensure transparency
• Confirm the reasons for unusually low fees from consultants
• Include a penalty clause in the contract for cases of collusion
• Avoid concentrating information with a single consultant and verify specifications by the management association itself

Frequently Asked Questions about Large-Scale Repairs in Nakahara Ward, Kawasaki City

How much does large-scale repair in Nakahara Ward, Kawasaki City cost?

For condominiums, according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for the fiscal year 2021, about 70% of cases fall between 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 ranges from 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment from 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings from 5,000,000 to 15,000,000 yen. The cost varies depending on the condition of the substrate and whether waterproofing or roofing work is required, so we provide free on-site estimates.

How often should large-scale repairs be conducted?

Generally, a cycle of 12 to 15 years is recommended, and the actual cycle is most commonly 13 years according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey, with about 70% falling within the 12 to 15-year range. However, the decision should be based on the condition of deterioration rather than just the number of years. If deterioration of sealing, tile lifting, or breaks in the waterproof layer are observed, it is advisable to carry out repairs without waiting for the cycle, as this can ultimately reduce costs. For 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 about 1.5 to 3 months, and for condominiums with over 50 units around 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, including distributing advance notices, providing information on the bulletin board regarding the schedule and laundry, 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 the repair committee, conducting building diagnostics, selecting contractors, and passing resolutions at general meetings, followed by 3 to 6 months for construction. Overall, it is advisable to plan for about 2 years to proceed comfortably. If utilizing subsidies or tax incentives, please also factor in the time required to obtain management plan certification (resolutions at general meetings, pre-checks, and applications to the city).

Are there any subsidies available for large-scale repairs in Nakahara Ward, Kawasaki City?

There are no subsidies for large-scale repair work itself from either Kawasaki City or Kanagawa Prefecture (Kawasaki City has indicated that there are no subsidies for exterior wall painting or roof repairs aimed at renovations). However, for condominium owners, if certain conditions are met, a 50% reduction in fixed property tax can be applied under the “Condominium Longevity Promotion Tax System.” Additionally, Kawasaki City offers free consultation services and advisor dispatch (up to 3 times for registered management associations), subsidies for eliminating steps in common areas (one-third of costs), assistance for investigating and removing sprayed asbestos, and subsidies for EV charging facilities and solar power/storage batteries for multi-family housing. If the work includes windows and insulation, it may be eligible for “Advanced Window Renovation 2026” or “Future Eco Housing 2026.” The timing of applications and applicants varies by program, so please check the eligibility conditions and application procedures for each program before contracting or starting work.

I heard that fixed property taxes 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 requirements such as being over 20 years old and having more than 10 units conducts large-scale repairs that contribute to longevity (including exterior wall painting, floor waterproofing, and roof waterproofing), the fixed property tax for the following year can be reduced by half for one unit equivalent to 100 square meters. This applies to work completed between April 1, 2023, and March 31, 2027, and a declaration must be made within 3 months of completion to the city tax office or tax division responsible for the building’s location (for Nakahara Ward, this is the Kosugi City Tax Division). 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?

There is. The national “Childcare Green Housing Support Project” has been abolished and reorganized into the successor “Mirai Eco Housing 2026 Project.” Management associations and management corporations can also become joint contractors, allowing for insulation renovations in common areas. Additionally, the “Long-term Excellent Housing Renovation Promotion Project” will end in the fiscal year 2025, and will not be implemented in fiscal year 2026. The “Advanced Window Renovation 2026 Project” has started accepting bulk applications for collective housing from May 29, 2026 (the application process is handled by registered contractors). Please be careful not to establish financial plans based on outdated information.

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

There are mainly four options. ① Postpone low-urgency repairs 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 loans for renovations of common areas in condominiums do not require collateral, and interest rates can be reduced by up to 0.6% per year by obtaining management plan certification and implementing energy-saving and seismic work. Please note that postponing waterproofing and tile peeling measures often ends up being more expensive, so please consult us for judgment on separation.

Can scaffolding be set up on sloped or uneven land?

Yes, it can. Nakahara Ward is mostly flat land along the Tama River, while the Idai area in the southwestern part, adjacent to Yokohama City, is a hilly area with remaining greenery. There are buildings on sloped and terraced land in hilly areas. Kakeru Koumuten Co., Ltd. owns its own scaffolding materials and has its own scaffolding team, allowing us to plan support and layout for the boards after confirming the site. This is a part where additional costs are likely to arise after seeing the site, so it is important to confirm the delivery route during the estimation stage. We also check for deterioration of retaining walls and slopes and consult on whether they are included in the long-term repair plan.

What will happen to the parking for residents during construction?

Vehicles on the side where scaffolding will be erected will need to be temporarily moved. In buildings with housing complexes or on-site parking, it may take time to secure a relocation spot 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, starting 2 to 3 months before construction begins.

Can I freely decide the color of the exterior walls?

This depends on the regulations affecting the building’s site. Nakahara Ward has eight districts under district planning, and there are specific areas under landscape planning (Musashi Kosugi area, Shinkawasaki area) and Tama River scenic areas (parts of Todoroki and Kosugi Jinya-cho 2-chome). There may also be areas with building agreements that specify the color and use of the exterior. The details vary by district. You can check what regulations apply to your site at the Kawasaki City district planning, landscape planning, scenic areas, and building agreement offices. We will also investigate during our survey and share the completion image through color simulations to assist in building consensus with management associations and neighbors.

Nakahara Ward is far from the sea, but are there any concerns regarding damage to exterior walls and metal parts?

Nakahara Ward is an inland ward not facing the sea, so salt damage from sea breezes is not a major concern. However, most of the ward is flat land along the Tama River, and during the Typhoon of East Japan in 2019, flooding occurred around the drainage pipes along the Tama River. There are Nakahara Ward versions of the flood hazard map and internal water hazard map in Kawasaki City, and for the hilly area of Idai in the southwestern part, there is a landslide hazard map (Kawasaki and Nakahara Ward version). The assumptions vary by site, so please check your own site. Additionally, for buildings facing busy pedestrian and bicycle routes around the station, as well as places close to commercial and residential areas, it is also important to consider the splatter from washing, the smell of paint, and the noise from deliveries. We will check the progression of rust on metal parts, the condition of sealing and waterproof layers, and around drains during the on-site survey, and we will specify the necessary scope in the estimate for waterproofing around the first floor, basement, and mechanical rooms, as well as the condition of retaining walls and slopes.

Which should I choose, the responsible construction method or the design management method?

In smaller buildings, the burden of consulting fees tends to be heavier, so we believe that the responsible construction method is often more suitable for small to medium-sized buildings. The design management 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 there are risks of conflicts of interest and collusion that need to be considered. Even with the responsible construction method, verification of price, specifications, and construction status is essential. Kakeru Koumuten Co., Ltd. provides estimates that clearly state quantities, methods, and materials for each construction item, allowing you to compare with other companies on the same level.

How can I detect collusion in large-scale repairs?

There are three typical methods. ① Deciding on a contractor in advance and having other companies provide only formal high estimates, known as “dummy estimates.” ② Consultants contract at extremely low design and supervision fees and receive kickbacks from partner contractors, leading to collusion. ③ Adding a portion of the contract amount as a back margin to the construction costs. Countermeasures include obtaining independent estimates, consulting a neutral third party, documenting the selection process in minutes, and including penalty clauses in contracts.

How many estimates should I obtain?

We recommend at least three companies. Too many will make it hard to compare, while too few will not create competition. The important thing is not the number of companies but to “compare after creating the same playing field.” By creating a common specification sheet and quantity table and requesting under the same conditions, and requiring detailed breakdowns instead of “one set” notation, it becomes clear whether the price differences are due to variations in scope or unit prices.

What is the difference if you own your own scaffolding?

In large-scale repair construction, temporary construction accounts for about 20% of the costs (according to the Ministry of Land, Infrastructure, Transport and Tourism’s fiscal year 2021 survey). By not outsourcing scaffolding work, it is easier to 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 about 100 detached houses and plans according to the site, even on slopes or uneven terrain.

I’m in the middle of obtaining estimates; can I just have my estimate reviewed?

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

Can I request just emergency measures for a leak?

Yes. As a preliminary step before large-scale repairs, we also accept requests for emergency measures for leaks or partial repairs. 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 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, there may be a possibility to use the Kawasaki City subsidy program (the cost of the survey is covered 100% up to 150,000 yen, and removal work is covered 2/3 up to 3,000,000 yen. Contracts before the grant decision are not eligible), so we will provide information on that as well.

What happens if large-scale repairs are not done?

There are risks such as personal injury from falling exterior tiles, structural deterioration due to corrosion of rebar, leaks, and a decrease in asset value. Furthermore, for buildings subject to regular reporting under Article 12 of the Building Standards Act, investigations are required under certain conditions, such as when more than 10 years have passed since completion or exterior wall renovations for tile or mortar-finished walls. While the list of regular reporting target uses in Kawasaki City does not include apartment buildings (mansions or apartments), the judgment for mixed-use buildings, including stores, varies by floor use and area, so individual confirmation is necessary. Even if not subject to statutory inspections, regular inspections and maintenance are essential, so please consult us if you are unsure.

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

For wooden two-story buildings with 6 to 10 units, it is estimated to be between 2,000,000 and 4,000,000 yen, and for three-story steel or RC buildings with 10 to 20 units, it is estimated to be between 4,000,000 and 9,000,000 yen based on our company’s track record (including scaffolding, substrate repairs, exterior wall painting, sealing, and waterproofing). It is common for apartments to undergo repairs every 10 to 15 years. For owners, there is an increasing trend to change the exterior appearance through color simulations during repairs to improve occupancy rates.

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

Our company handles many exterior wall renovations and large-scale repairs for condominiums and apartments in Nakahara Ward, Kawasaki 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 indoors are hot”, we will propose the best solutions for your specific requests and future repair plans.

From temporary scaffolding work to roof construction and exterior painting, all work is performed by our company’s own team. We are confident that we won’t be outdone in terms of cost, quality, and efficiency compared to other companies, so we welcome competitive quotes!

Large-scale Repair Work Service Area

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

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