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

Large-Scale Repairs for Condominiums, Apartments, and Buildings in Odawara City

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

Large-scale repairs are not just “exterior painting” or “waterproofing,” but a comprehensive repair work that addresses the deterioration 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 by Building Diagnosis

It is not guaranteed that all of the above works will be carried out. The extent of the work will be determined based on the results of the building diagnosis. At Kakeru Koumuten Co., Ltd., we conduct a free on-site survey to confirm the items below, compile them into a deterioration diagnosis report with photos, and propose the scope of work.

Reasons Kakeru Koumuten is Chosen for Large-Scale Renovations in Odawara City

The reason why we can be entrusted with large-scale renovations in Odawara City is partly because “Kakeru Koumuten has a base in Yokohama City”, but also due to our “unique initiatives in large-scale renovation 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 renovations. 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 renovations and can assemble the scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can cut costs on scaffolding work and provide quick and flexible responses.
We have approximately enough scaffolding materials for 100 single-family homes!

Storage of Materials in Our Large In-house Warehouse

We store paints and substrate repair materials used for exterior renovations. By ordering a large quantity of materials at once, we can purchase materials at lower prices! Additionally, we always have stock available, allowing us to respond quickly in emergencies!

In-house Waste Sorting

Large-scale renovations generate various types of waste, including leftover paint, metals, and wood. At Kakeru Koumuten, we sort and recycle waste 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 representative does not change, smooth communication is possible.

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

3. Various Permits and Skilled Workers

We have obtained permits for the construction industry and for the collection and transportation of industrial waste! We also have nationally certified sheet metal and painting technicians on staff, and we are confident in our construction techniques. We can also handle large-scale roofing work for factories! We have qualified personnel for asbestos work supervisors and building materials containing asbestos investigators, so we can handle and conduct preliminary surveys for roofing materials containing asbestos.

4. Warranty and Aftercare

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

5. Flexible and Prompt Response

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

We can also address exterior walls and rooftops that cannot be checked from high places using drones! During 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 urgent repairs for sudden leaks! We will promptly respond to emergency requests or urgent inquiries!

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 effectively. We also educate on points to pay attention to and areas to check during large-scale repair work.

7. Consideration for Residents and Neighbors

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

8. Strict Quality Control

Each process is inspected by a responsible person, and detailed construction photos are taken. We use film thickness inspection equipment and check sheets to ensure that no inspections are overlooked. When performing exterior wall painting or waterproofing work, we verify the quantity of used paint cans to ensure that the specified amount of paint is used, and we prevent construction defects by ordering paint in-house. Of course, we will also take photos of used paint and report them.

9. Exterior Wall Painting Color Simulation

9-1 Self Color Simulation

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

* In Odawara City, there are key areas for landscape planning and scenic districts, and depending on the site, procedures such as notifications or permits may be required when changing the color of the exterior walls. There are also sites that require confirmation of district plans and 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 test paint!

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

9-3 Exterior renovation simulation

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

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

Cost Estimates for Large-Scale Repairs in Odawara City

The cost of large-scale repairs varies significantly depending 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 each type of work.

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

According to a survey conducted by the Ministry of Land, Infrastructure, Transport and Tourism, which compiled 818 construction cases (FY 2021), approximately 70% of the costs for large-scale 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 costs, so they differ from the current total construction costs including tax.

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

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

Source: Ministry of Land, Infrastructure, Transport and Tourism “Fiscal Year 2021 Survey on Large-Scale Repair Work for Condominiums” (Second survey of large-scale repair work. The overall average is 59.0% for construction-related, 22.3% for temporary works, and 9.9% for miscellaneous expenses). *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 is an estimate based on Kakeru Koumuten’s construction performance and may vary depending on the presence of roofing work, metal work, plumbing, etc. For condominiums, please also consider the amount obtained by multiplying the above national statistics (750,000 – 1,500,000 JPY per unit) by the number of units as a guideline.

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

Estimates for large-scale repairs are 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 depending on shape, quantity, substrate condition, and type of materials. If you would like a detailed estimate, please feel free to contact us. Estimates are completely free.

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

“Good paint 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 that are exposed to sea breezes, selecting highly weather-resistant paint 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

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

Source: Ministry of Land, Infrastructure, Transport and Tourism “Guidelines on Repair Reserve Funds for Condominiums” (Reiwa 6, June Revision, PDF) / National average is 13,378 JPY per unit per month (Reiwa 5 Fiscal Year Comprehensive Survey on Condominiums)

In the 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 Odawara City

The list of housing subsidy systems in Odawara City does not include subsidies specifically for large-scale renovation work on condominiums (Kanagawa Prefecture also does not have subsidies aimed at the work itself). The main options available are the following four types. The eligibility and application status of these systems may change during the fiscal year, so please be sure to confirm with our company or each contact point before contracting or starting work. (As of October 8, 2026)

① Condominium Longevity Promotion Tax System (Property Tax Reduction)

If large-scale repairs (such as exterior painting, floor waterproofing, and roof waterproofing) that contribute to the longevity of condominiums meeting certain requirements are carried out, the property tax amount for the following year will be reduced by half (the reduction lasts for one year, up to 100㎡ of the residential floor area per unit; urban planning tax is not reduced). According to the information from Odawara City, buildings that include uses other than residential must have at least half of their area as residential to be eligible.

Source: Odawara City “Condominium Long-term Life Promotion Tax System” (Updated April 10, 2025)

② Support for Condominium Management and Earthquake Resistance Subsidies in Odawara City, Kanagawa Prefecture (Management Associations Start Here)

The Urban Policy Division of Odawara City offers free management consultations for board members, unit owners, and residents of condominium management associations. Additionally, the Kanagawa Prefecture condominium advisor dispatch is available for management associations in the prefecture excluding Yokohama City, Kawasaki City, Sagamihara City, and Yokosuka City, and Odawara City management associations can also utilize this service.

Source: Odawara City “Condominium Management Consultation” (Updated March 16, 2026) / Kanagawa Prefecture “Condominium Advisor Dispatch” (Updated June 26, 2026) / Odawara City “Subsidies for Seismic Diagnosis and Renovation of Wooden Houses” (Updated May 11, 2026)

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

This is a system certified by Odawara City, and upon certification, you may receive interest rate benefits for the “Condominium Common Area Renovation Loan” from the Japan Housing Finance Agency and Flat 35 (Maintenance Type), which is also one of the requirements for the Long-Term Durability Promotion Tax System (certification alone does not guarantee tax reduction). According to the city’s guidance, before applying, you should receive a pre-confirmation through the condominium management center’s procedural support service, and then apply to the city.

*The pre-confirmation fee is set by the condominium management center, and the application fee for the city is not listed on the city’s page. The validity period of the certification is 5 years, and renewal is required. For procedures and costs, please check with the Urban Policy Division (0465-33-1307).

④ National Energy Saving Support | Housing Energy Saving 2026 Campaign

Changes for 2026The “Child-Rearing Green Housing Support Project” for 2025 has been abolished and reorganized into the successor “Mirai Eco Housing 2026 Project.” Additionally, the “Long-Term Excellent Housing Renovation Promotion Project” will end in Reiwa 7, and will not be implemented in Reiwa 8. Please be careful not to base your financial plans on outdated information.

Mirai Eco Housing 2026 Project

Advanced Window Renovation 2026 Project

⑤ Kanagawa Prefecture Subsidies (Applications for FY2026 have ended)

*The subsidy for existing housing energy saving renovation costs does not cover common areas of rental apartments or units not occupied by the owner.

⑥ Financing System (Housing Finance Agency Mansion Sumairu Loan)

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

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

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

Building Conditions and Repair Points in Odawara City

Odawara City is located in the western part of Kanagawa Prefecture, facing Sagami Bay, with an area of approximately 114.06 km². According to the city’s planning documents, the western part features mountainous areas such as the Hakone volcano, while the eastern part has the Oiso Hills, with the Sakawa River flowing through the central area and plains like the Ashigara lowlands spreading out. The city is broadly divided into four areas: “forest (mountain forest), village (farmland), town (urban area), and sea,” with the urbanized area covering about 27.97 km² (as of April 1, 2014), which is approximately one-fourth of the total area. Historically, in the 15th century, the Omori clan established a castle town, and in the 16th century, the Hojo clan made it their base, flourishing as a post town on the Tokaido during the Edo period. After the reconstruction following the Great Kanto Earthquake in Taisho 12 (1923) and the post-war reconstruction and land readjustment in Showa 20 (1945), the division between urbanized and urbanization control areas was established in Showa 45 (1970), leading to the expansion of the urban area. The coexistence of the castle town’s urban area, the plains along the Sakawa River, the seaside along Sagami Bay, and the slopes of the mountains, each with distinct characteristics, serves as a starting point for considering large-scale repairs in Odawara City.

Source: Odawara City “Mini Statistics” (September issue of Reiwa 8. Population and number of households, based on the prefectural population statistics survey as of January 1, Reiwa 7, with age divided into three categories)／Planning documents regarding greenery in Odawara City (around Heisei 27. Area, topography, history)／Odawara City Condominium Management Improvement Plan (Revised August of Reiwa 6. Number of condominium units and buildings)　*The survey points differ for each table, so the timing is noted for each value.

We will also confirm the composition of generations and households. As of January 1, Reiwa 7, the age distribution is as follows: the youth population (ages 0-14) is 10.3%, the working-age population (ages 15-64) is 58.3%, and the elderly population (ages 65 and over) is 31.4% (percentages based on 182,521 people, excluding 3,229 people with unspecified ages). Based on the population and number of households, there are approximately 2.2 people per household. Since the reference dates for population, number of households, and age distribution differ, these figures are merely guidelines. These are overall city figures and do not represent the situation of individual building occupants; the composition of generations varies even within the same city depending on the location.

Buildings in Odawara City are divided into “four faces”

Odawara City has significantly different environments across its districts: the castle town urban area, the plains of the Sakawa River basin, the seaside along Sagami Bay, and the slopes of the mountains. The major repairs that will be prioritized in your next large-scale renovation will vary depending on where your building is located. Additionally, since the history of rebuilding and large-scale renovations differs for each building, please consider the age of the building as a guideline.

Source: Odawara City Green Planning Document (around 2015) / Odawara City “Various Hazard Maps” (Updated December 4, 2025. The comprehensive hazard map was issued in September 2022) / Odawara City “Notifications Based on the Landscape Plan” (Updated June 2, 2025) *The correspondence between district names and locations is organized by our company based on the district names and town names listed in the city’s documents, and the boundaries are not strict.

The city’s plan also includes the results of the actual survey for the fiscal year 2023. Of the 66 responses received, 67.7% (44 responses) have created long-term repair plans, while 18.5% (12 responses) have not, and 15.2% (10 responses) are properties built to old seismic standards. Additionally, 93.3% (56 responses) have experience with large-scale repair work. The city aims to increase the percentage of management associations that have created long-term repair plans of 30 years or more from 48% at the time of the survey to over 65% by fiscal year 2030. The numbers from the responding management associations do not represent the situation of all condominiums in the city.

Four Unique Factors That Damage Buildings in Odawara City

The contents of large-scale repairs vary depending on the location of the building. When investigating buildings in Odawara City, the following four factors are particularly important to check. While I will discuss based on the overall trends in the city, the actual conditions differ from building to building, so it is essential to confirm on-site.

Source: Odawara City “Various Hazard Maps”／Odawara City “Notifications Based on the Landscape Plan”／Odawara City “Mini Statistics” (September 2026)／Odawara City Green Planning Documents (around 2015)／Odawara City Apartment Management Improvement Promotion Plan (revised August 2024)

Key Points to Consider When Proceeding with Construction in Odawara City

* Kakeru Koumuten has five locations, including a showroom and material storage, in Yokohama City, and we handle consultations throughout Odawara City, including around Odawara Station, Kamonomiya, Kōzutsu, Hayakawa, Nebukawa, Soga, and Kuno.

Signs of Deterioration Requiring Major Repairs and Timing

Generally, large-scale repairs are recommended every 12 to 15 years. According to a survey by the Ministry of Land, Infrastructure, Transport and Tourism, the actual repair cycle is most commonly 13 years, with about 70% falling within the 12 to 15 year range, and the cycle tends to shorten with each occurrence. However, the actual decision should be based on the condition of deterioration rather than just the number of years, so if you observe symptoms like those listed below, we recommend an early on-site inspection.

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

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

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

Examples of Large-Scale Renovation Work

This is an example of exterior renovation work on a mixed-use building undertaken by Kakeru Koumuten Co., Ltd. The building had leaks occurring in several places, and we combined clear waterproofing for the tile exterior 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 necessary, so it is advisable to start moving 1 to 1.5 years before the desired start date to proceed with ample time.

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 roof, high places, and leak areas using drones or thermal imaging. For properties in Odawara City, we will check for rust on metal parts of buildings close to the sea, assess the potential for flooding, storm surges, tsunamis, and landslides, as well as the condition of slopes and retaining walls, and confirm the delivery route 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 through color simulations, paint boards, and trial painting. For management associations, we will assist in preparing materials for general meetings. In areas subject to landscape plans, scenic districts, 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 notifications, visit neighbors to greet them, and set up a bulletin board at the entrance (construction schedule and laundry information). If temporary relocation of parking is necessary, adjustments will be made at this stage.
6. Installation of Temporary Scaffolding & Various Works Our own scaffolding team will set up the scaffolding, followed by high-pressure washing → substrate repair → sealing → exterior wall painting & tile repair → waterproofing → metal parts & ancillary work in that order. A supervisor will inspect each process and take construction photos.
7. Completion Inspection, Scaffolding Dismantling & Handover We will confirm the finish in the presence of the customer and provide construction photos, a report on the paint used, and a warranty certificate.
8. Aftercare Maintenance We will send out annual DM notifications, and inspections can be conducted every year. Simple repairs such as partial sealing are provided free of charge.

Resident Communication, Approval for Additional Work, Inspection Reports

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

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

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

There are many large-scale repair contractors that cover the Odawara City area, and you may be unsure which one 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 achievements. If they provide detailed explanations of repair contents with photos, it offers reassurance 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, content of explanations, and management system.

Large-scale repair work involves not only the construction itself but also the potential for troubles with residents and neighbors. Therefore, it is necessary to report 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 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 free repairs, providing peace of mind! Companies that offer warranty periods are often confident in their work, making this a key criterion for selecting a contractor.

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

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

Obtain estimates from multiple contractors (at least 3 companies)

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

When comparing estimates, be sure to look atnot just the costs, but also“the items in the estimate,” “the methods and materials for substrate repair and exterior painting,” and “confirmation of the process.” Carefully compare these details! Costs can be lowered by using lower-grade materials or skipping processes, so avoid making decisions based solely on price. Especially since substrate repair work can be difficult to assess from appearance alone, ensure that the repair method is appropriate for the condition of the substrate!

Check these points on the estimate (checklist)

Check if it is managed in-house

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

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

Additionally, contractors that outsource to subcontractors may also have delayed responses in case of any troubles during construction. It is safer to avoid having a company that has not actually met with the customer manage the construction. Kakeru Koumuten performs everything from temporary scaffolding setup to exterior wall painting and waterproofing work in-house, with knowledgeable and experienced personnel managing the construction!

There are three ordering methods. The choice affects the approach.

Especially for management associations, it is necessary to decide “how to request” before “which company to ask.” The main ordering methods are the following three.

Collusion and Inappropriate Consulting Issues in Large-Scale Renovations and Self-Defense Measures

Latest 2026 In the large-scale renovation industry, inappropriate orders linked between design consultants and construction companies have long been a problem. The Ministry of Land, Infrastructure, Transport and Tourism issued warnings and notifications to management associations in January 2017 and April 2023, and on September 28, 2026, the Japan Fair Trade Commission announced that it had issued exclusion orders to 38 companies and a total of 1.63788 billion yen in surcharge 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 consulting fees.
• Include a penalty clause in the contract for cases of collusion.
• Avoid concentrating information with a single consultant and verify specifications independently.

Frequently Asked Questions about Large-Scale Repairs in Odawara City

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

For condominiums, according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey for the fiscal year 2021, about 70% fall within the range of 750,000 to 1,500,000 yen (excluding consumption tax and common temporary construction costs), with the most common range being 1,000,000 to 1,250,000 yen. Based on our construction records, the cost for a two-story wooden apartment is around 2,000,000 to 4,000,000 yen, for a three-story steel or RC apartment it is about 4,000,000 to 9,000,000 yen, and for small condominiums or mixed-use buildings, it ranges from 5,000,000 to 15,000,000 yen. Costs may vary depending on the condition of the substrate and whether waterproofing or roofing work is required, so we provide free on-site estimates.

How often should large-scale repairs be conducted?

Generally, a cycle of 12 to 15 years is recommended, and the actual cycle is most commonly 13 years according to the Ministry of Land, Infrastructure, Transport and Tourism’s survey, with about 70% falling within the 12 to 15-year range. However, the decision should be based on the condition of deterioration rather than just the number of years. If there are signs of deterioration in the sealing, lifting of tiles, or ruptures in the waterproof layer, it is better to repair them without waiting for the cycle, as this can ultimately reduce costs. For older buildings, the proportion of tile repairs and replacement of iron parts tends to increase in the second and third rounds of repairs.

How long will the construction period be? Can residents stay during the work?

For apartments, the construction period is typically 3 weeks to 2 months, for small condominiums or buildings it is about 1.5 to 3 months, and for condominiums with over 50 units, it takes around 4 to 6 months. Residents can remain in their homes during the construction. However, there will be restrictions on drying laundry outside and opening windows while scaffolding is in place, so we take thorough measures to minimize the impact on daily life, including distributing advance notices, providing information on the schedule and laundry through bulletin boards, and strictly adhering to working hours.

How long should I expect from the start of planning to the completion of construction?

For management associations, it typically takes 1 to 1.5 years for the establishment of the repair committee, building diagnosis, contractor selection, and general meeting resolutions, followed by 3 to 6 months for construction. Overall, it is advisable to plan for about 2 years to proceed comfortably. If you are using subsidies or tax incentives, please also factor in the time required to obtain management plan certification (resolutions at general meetings, prior confirmations, and applications to the city).

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

The list of housing subsidy programs in Odawara City does not include subsidies specifically for large-scale repair work on condominiums (there are also no subsidies for the work itself in Kanagawa Prefecture). However, if it is a condominium, you can use a 50% reduction in fixed property tax under the “Condominium Longevity Promotion Tax System” if certain conditions are met. Additionally, there is free consultation for condominium management in Odawara City and free dispatch of condominium advisors from Kanagawa Prefecture (applications accepted until February 26, 2027). If the work includes windows and insulation, it may be eligible for “Advanced Window Renovation 2026” and “Mirai Eco Housing 2026.” The timing of applications and applicants varies by program, so please check the eligibility conditions and application procedures for each program before contracting and 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 is over 20 years old and has more than 10 units conducts large-scale repairs (such as exterior painting, floor waterproofing, and roof waterproofing) that contribute to longevity, the fixed property tax amount for the following year will 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 Asset Tax Division of Odawara City within three months of completion. For certified management plan condominiums, there are also requirements such as raising the repair reserve fund, which takes time to prepare, so it is recommended to start the process more than a year in advance.

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

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

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

There are mainly four options: ① Postpone low-urgency work after a deterioration diagnosis, ② Review the scope and specifications of the work, ③ Check for support systems such as subsidies, ④ Consider increasing the repair reserve fund or 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 costly, so please consult us for a decision on separating these issues.

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

Yes, it can. Odawara City includes low-lying areas along Sagami Bay, plains in the Sakawa River basin, and mountainous regions such as the Hakone volcano, with buildings on sloped or terraced sites. Kakeru Koumuten Co., Ltd. owns its scaffolding materials and has its own scaffolding team, allowing us to plan support and layout for the boards after checking the site. This is a part where additional costs can easily arise after inspecting the site, so it is important to confirm the delivery route during the estimation phase. We also check the deterioration of retaining walls and slopes and discuss 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 many units or those with on-site parking, securing a place for moving vehicles may take time depending on the number and arrangement. Kakeru Koumuten Co., Ltd. will coordinate with you about the availability of nearby coin parking and monthly parking spaces starting 2 to 3 months before construction begins.

Can I freely choose the color of the exterior walls?

This depends on the regulations affecting the property. Odawara City has key areas of landscape planning (such as around Odawara Castle and Odawara Station) and scenic districts, and in some cases, notification or permission may be required when changing the color of the exterior. There are also district plans and building agreements that apply to certain properties, and the details vary by area. You can check what regulations apply to your property at the Odawara City landscape planning, scenic district, district plan, and building agreement office. Our company will also investigate this during our survey and share a color simulation to help facilitate agreement with the management association and neighbors.

Do buildings near the sea need salt damage measures?

Odawara City faces Sagami Bay, and for buildings close to the sea, salt carried by sea breezes can adhere to exterior walls, metal parts, and fittings, accelerating rust. 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 measures are universally necessary. We will check the progression of rust on metal parts and fittings during the on-site survey, and after thoroughly washing away the salt with high-pressure cleaning, we will propose specifications that include highly weather-resistant paint and rust prevention.

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

The smaller the number of units, the heavier the burden of consulting fees, so 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, but it incurs separate consulting fees and requires caution regarding conflicts of interest and collusion risks. Verification of price, specifications, and construction status is essential even under the responsibility construction method. Kakeru Koumuten Co., Ltd. provides estimates that clearly state quantities, methods, and materials for each construction item, allowing you to compare with other companies on the same level.

How can I detect collusion in large-scale repairs?

There are three typical tactics: ① Deciding on a contractor in advance and having other companies submit only nominally high estimates, known as “dummy estimates,” ② A consultant contracts at an extremely low design supervision fee and receives kickbacks from partner companies, indicating 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 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 conditions for comparison.” By creating a common specification sheet and quantity list and requesting under the same conditions, and making detailed breakdowns mandatory instead of allowing “one set” notation, it becomes clear whether the price differences are 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 keep costs down in this area, and our in-house scaffold team can flexibly respond to sudden changes or additional work. Kakeru Koumuten Co., Ltd. owns scaffold materials for approximately 100 single-family homes and plans according to the site, even on slopes or uneven terrain.

I’m in the middle of comparing estimates, but can I just have a look at the estimate?

Of course, that’s possible. If you bring in estimates from other companies, we will check for free whether the items, quantities, methods, and materials are appropriate, and provide you with an estimate under the same conditions. We welcome comparative 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, including asbestos work supervisors and investigators of asbestos-containing building materials, who can handle everything from the legally required preliminary investigation to the cover method and removal of asbestos-containing roofing materials. If there is sprayed asbestos, we will also provide guidance on the investigation and removal process, as well as the legal procedures involved.

What happens if large-scale repairs are not done?

There are risks such as personal injury from falling exterior wall tiles, structural deterioration due to corrosion of rebar, leaks, and a decrease in asset value. Furthermore, for buildings subject to periodic reporting under Article 12 of the Building Standards Act, investigations through full tapping, etc., 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. According to the regulations in Odawara City, the cycle for periodic reporting of buildings is scheduled to be revised every three years (scheduled for April 1, 2026), and it is necessary to confirm with the city’s Building Guidance Division whether general apartments and condominiums are included in the applicable uses and scales. Even if not subject to statutory investigations, regular inspections and maintenance are essential, so please consult us if you are unsure about your decision.

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

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

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

Our company handles many exterior wall renovations and large-scale repairs for condominiums and apartments in Odawara 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 comparative estimates!

Areas Covered for Large-Scale Repair Work

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

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