Hello! This is Kakeru Koumuten Co., Ltd.!
This time, I would like to explain in detail about 【Renovation after purchasing a used property】!
‘I bought a used property, but there are many places that need roof repairs and renovations…’
‘I want to renovate a used detached house, but what should I do first?’
‘Is there a way to renovate at a lower cost after purchasing a used property?’
I will explain to help alleviate those doubts and concerns!
About Renovation of Used Detached Houses
Wooden Detached Houses
First, the rules for large-scale repairs and renovations of wooden detached houses will change due to legal amendments starting from April 2025.
Until now,
(Before Amendment)
○ Outside urban planning areas, quasi-urban planning areas, and quasi-landscape districts
Wooden buildings with two stories or fewer and a total floor area of 500㎡ or less are exempt from building confirmation
○ Inside urban planning areas, quasi-urban planning areas, and quasi-landscape districts
Wooden buildings with two stories or fewer and a total floor area of 500㎡ or less are subject to exemption from review if designed and supervised by an architect
For wooden single-family homes below this certain scale, building confirmation applications were not required even for large-scale repairs or renovations.
However, starting from April 2025,
(After Amendment)
○ Outside urban planning areas, quasi-urban planning areas, and quasi-landscape districts
Regardless of structure, buildings with two stories or more or a total floor area exceeding 200㎡ are subject to building confirmation
○ Inside urban planning areas, quasi-urban planning areas, and quasi-landscape districts
Buildings other than single-story buildings with a total floor area of 200㎡ or less are required to undergo structural reviews regardless of structure (Energy-saving standards are also subject to review for the same scale)
This change means that for wooden single-family homes exceeding this certain scale, building confirmation applications will be required for large-scale repairs or renovations.
A building confirmation application is a request to the authorities stating, “We will carry out this kind of repair or renovation.”
When Building Confirmation Application is Required
・It takes time and costs money
When applying for building confirmation, it is necessary to submit a structural calculation document along with the application.
This structural calculation document is not a simple paper; it must be prepared by a design office or a specialist, costing around 200,000 to 500,000 yen.
A point to note is that if there is no inspection certificate proving that the building was constructed according to the contents of the building confirmation application, you cannot apply for building confirmation. Therefore, it is also necessary to conduct this inspection, which will further increase costs and time. So, in advance, check the presence or absence of the inspection certificate for the house you purchased second-hand or plan to purchase!
For details on large-scale repairs and renovations of wooden detached houses,
please refer to items 1 to 3 from the Ministry of Land, Infrastructure, Transport and Tourism!
About Roof Renovation and Exterior Wall Repair Work for Detached Houses
So, what about roof repairs and exterior wall painting work!?
The answer is that for roof repairs, roof renovations, and exterior wall repair work on wooden, steel-framed, and reinforced concrete detached houses,
they generally do not fall under large-scale repairs or renovations, and construction confirmation applications are mostly unnecessary!
Treatment under the Building Standards Act for Roof Renovation Work
○ The act of only renovating roofing materials can be treated as not falling under large-scale repairs as defined in Article 2, Item 14 of the law, and not falling under large-scale renovations as defined in Item 15 of the same article.
○ Additionally, renovations using the so-called cover method, where a new roof is placed over the existing roof, can also be treated as not falling under large-scale repairs and not falling under large-scale renovations as defined in the same articles.
Treatment under the Building Standards Act for Exterior Wall Renovation
○ The act of only renovating exterior wall materials or conducting insulation renovations from the inside of the exterior wall can be treated as not falling under large-scale repairs and not falling under large-scale renovations as defined in Article 2, Item 14 and Item 15 of the law.
○ However, even if the act is only renovating exterior wall materials, if it corresponds to renovating all of the exterior wall, this does not apply.
○ The act of renovating by covering the existing exterior wall with new finishing materials can also be treated as not falling under large-scale repairs and not falling under large-scale renovations as defined in the same articles.
① Renovation of only exterior wall materials
② Insulation renovation from the inside of the exterior wall
(Excerpt from the Ministry of Land, Infrastructure, Transport and Tourism)
For details on roofs, exterior walls, as well as floor renovations, stair renovations, and extensions or alterations,
please refer to items 4 to 9 from the Ministry of Land, Infrastructure, Transport and Tourism!
Possible Subsidies for Purchasing Used Detached Houses in Yokohama
①Long-Term Quality Housing Reform Promotion Project
Under this subsidy program, not only wooden houses but also those that meet the conditions can apply and receive subsidies, making it possible for buyers of used detached houses to renovate at a lower cost. If you’re interested, please take a look!
Project Overview
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NameLong-Term Quality Housing Reform Promotion Project
-
This project has a “Year-Round Application Type,” which accepts applications at any time, and a “Pre-Selection Type,” which accepts applications after a public recruitment and selection process.
①Pre-Selection Type ・You must apply during the designated recruitment period.
・Multiple houses can be applied for collectively by the business entity.②Year-Round Application Type ・Applications are accepted at any time within the eligible period.
・Applications can be made for those that meet either the evaluation criteria type or the certified long-term quality housing type. -
Overview
Project Type / Application Type Year-Round Application Type Pre-Selection Type Safe R Housing Evaluation Criteria Type 〇 × 〇 Certified Long-Term Quality Housing Type 〇 × 〇 Proposal Type × 〇 × -
Subsidy AmountThe total of 1) and 2) below
1) Subsidy amount related to renovation work
a. Specific performance improvement renovation work
b. Other performance improvement renovation work
c. Renovation work for multi-generational living
d. Renovation work for child-rearing households
e. Renovation work to improve disaster resilience and resilience2) Subsidy amounts related to inspections, etc.
① Costs for inspections of existing homes conducted prior to renovation work
② Costs for creating renovation work history information
③ Costs for creating maintenance and preservation plans
④ Insurance premiums for renovation defect insurance -
Subsidy limit amount（Subsidy upper limit）
Business Type Subsidy Limit Amount Evaluation standard type 800,000 yen per housing unit※1 Certified long-term excellent housing type 1,600,000 yen per housing unit※1 In the following cases, an additional 500,000 yen is added, up to the limit
When implementing renovation work for multi-generational living / When young or child-rearing households implement renovation work / When purchasing existing homes and implementing renovation workSubsidy amounts of 100,000 yen (subsidized construction costs of 300,000 yen) or less per application are not eligible for subsidies. -
Method of refunding subsidies
Contractors will refund the granted subsidies in a manner agreed upon in advance with the subsidy recipients. Either ① Method of applying to the contract price related to the subsidy project (limited to final payments) ② Method of payment in cash Buy-and-resell businesses are not required to refund the subsidies to the buyers, but must explain to the buyers that they have received this subsidy before concluding the sales contract. -
Applicant (business registration required)・Contractors for renovation work
・Buy-and-resell businesses -
Eligible period（Year-round application type）
Business Registration Period May 20, 2025 –October 31, 2025 Housing Registration Period May 20, 2025 –October 31, 2025 Application Submission Period 【Phase I】
Certified Long-term Excellent Housing Type
＜Single-family Homes＞
May 30, 2025 (Fri) –September 30, 2025
＜Multi-family Housing＞
June 13, 2025 (Fri) –September 30, 2025Evaluation Standard Type
＜Single-family Homes＞
June 13, 2025 (Fri) –September 30, 2025
＜Multi-family Housing＞
June 27, 2025 (Fri) –September 30, 2025【Phase II】
October 6, 2025 (Mon) – November 14, 2025 (Fri) 17:00
There is no distinction between Certified Long-term Excellent Housing Type and Evaluation Standard Type.Completion Report Submission Period July 1, 2025 –February 20, 2026 Single-family Homes: Detached houses, mixed-use residential and commercial buildings
Multi-family Housing: Multi-family housing/row houses (one building application), multi-family housing/row houses (unit application)(Pre-approval type)
No selections for this fiscal year (Excerpt from the Long-term Excellent Housing Renovation Promotion Project HP)
② Child-rearing Eco Home Support Project・Advanced Window Renovation 2024 Project・Hot Water Energy Saving 2024 Project
This subsidy program is also available for those who have purchased used single-family homes.
Each year, there are limits and deadlines for the budget, so if you are interested, please check the official HP of the Ministry of Land, Infrastructure, Transport and Tourism!
Here is the article on our website introducing the above subsidy program⇩
【2024 Edition】Introducing subsidies and grants available for renovations in Yokohama City!
Summary
In this article, we have introduced content for those who have purchased or are planning to purchase a used property!
If you are considering or have concerns about renovations, please feel free to consult Kakeru Koumuten Co., Ltd.
Thank you for reading until the end!
Our articles on vacant house renovations can be found here⇩
As our company is based in Yokohama, Kanagawa Prefecture, we also highlight nearby areas such as Yokohama and Tokyo!
There is a high possibility that support projects related to vacant houses may also be available for those living in other regions, so please search online for “your area vacant house subsidies” and make use of any subsidy systems available!
⇨Introducing the latest subsidies and grants for vacant house renovations as of 2024!
Leave your renovations to Kakeru Koumuten Co., Ltd.!
We are happy to assist with everything from rain gutter cleaning and partial rain gutter repairs to roof repairs and exterior painting work, as well as interior repairs and renovations.
If you have any concerns or questions such as “I just want to know the estimate” or “I want to have an inspection,” please feel free to contact us!
Estimates and inspections are, of course, free! If you have any issues with your roof, rain gutters, exterior walls, exterior structures, or interiors, please consult Kakeru Koumuten Co., Ltd. in Aoba-ku, Yokohama!
Kakeru Koumuten is a renovation company strong in exterior renovations, and we carry out complete in-house construction from temporary scaffolding to roof work and exterior painting.
Regarding exterior renovation work, we are confident that we will not be outdone by other companies in terms of “cost, quality, and efficiency”!
We are confident in our exterior renovations, so we welcome competitive estimates!
We offer comprehensive construction guarantees and aftercare maintenance, and we have received positive feedback for our cost performance and appropriate proposals that align with our customers’ future life plans!
We want you to feel, “I’m glad I asked them!” We take every request seriously and work diligently on it.
We look forward to your inquiries. Thank you very much.
Helpful information about exterior renovations can be found here!
・Estimate your costs yourself!! Easy exterior renovation estimate simulation!
・Exterior wall cleaning plan that does not require temporary scaffolding!
・About the costs of roof overlays | Kakeru Koumuten’s roofing plans!
・About the costs of exterior painting | Kakeru Koumuten’s exterior painting plans!
・About the costs of leak repairs | Kakeru Koumuten’s leak repair plans!
・About the costs of ridge cap replacement and surface plaster | Kakeru Koumuten’s construction plans!
・What are the average costs of roof renovations? Types of work and how to choose a contractor
・How much does roofing work cost? We will introduce the average costs!
・Latest! Renovation subsidies! We will introduce grants and reduction systems!
・Renovation store in Yokohama, Kanagawa | What is roof overlay (roof cover method)?
・What are the average costs of leak repairs? We will guide you to reliable repairs!
LINE consultations are also very welcome◎
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AAA is a young company with an average age in the early 20s, but our technology is second to none.
One of our greatest strengths is that we can do all of our own scaffolding, roofing, and painting work. In this industry, where work is generally divided, we are able to provide a complete set of services, which saves time and effort in management and reduces costs. Above all, if there is any trouble, we will come to you right away!
We can confidently declare this. We are the youngest and most friendly renovator in Kanagawa!
