Leave Your Solar Panel Installation Work in Akishima City, Tokyo to Kakeru Koumuten Co., Ltd.!
For Solar Panel and Battery Installation in
Akishima City, Tokyo,
trust Kakeru Koumuten!
Kakeru Koumuten is a company specializing in exterior renovations.
As a strong player in roofing, we are entrusted withsolar panel and battery installation considering roofs and waterproofing!
“How to Choose a Solar Panel Contractor in Akishima City, Tokyo”
“Costs for Solar Panel and Battery Installation”
“Subsidies Available for Solar System Installation in Akishima City, Tokyo”
We will also explain the above three points!
Installing solar panels carries risks, such as“the occurrence of leaks”,
so we recommend obtainingthree estimates to avoid regrets!
Table of Contents (Tap to Open/Close)
- Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Akishima City, Tokyo
- Roof Inspection Before Installing Solar Panels
- Possible Subsidies and Grants Available in Akishima City, Tokyo
- Price List for Solar Panel and Storage Battery Installation
- Breakdown of Installation Capacity, Equipment, and Construction Costs
- Self-Estimate and Profit Simulation for Solar Power Generation
- Customer Testimonials
- Case Studies of Solar Panel Installations
- How to Choose a Solar Panel Installation Contractor in Akishima City, Tokyo
- Benefits of Introducing Solar Equipment
- Points to Consider When Introducing Solar Power Generation
- How to Choose Solar Panels
- Frequently Asked Questions About Solar and Storage Battery Installation in Akishima City, Tokyo
- If You Are Looking for a Solar Panel Installation Contractor in Akishima City, Tokyo, Contact Kakeru Koumuten
- Characteristics of Akishima City, Tokyo and Points for Solar Construction
- Service Area in Akishima City, Tokyo
Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Akishima City, Tokyo
Regarding the reasons why our company is entrusted with solar panel installation by customers in Akishima City, Tokyo,
“Our Unique Strengths in Solar Panel Installation That Cannot Be Imitated by Other Companies”
have received high praise from many customers.
We would appreciate it if you could compare our estimates with those of other companies.
Because we are confident, we welcome estimates from any number of companies!
1. We Also Handle Exterior Renovations Beyond Solar Panel Installation!
Troubles such as leaks caused by solar panel installation may be due to insufficient checks on the roof and waterproofing at the installation site.
Even if you are knowledgeable about solar panels, there may be cases where the roof and waterproofing at the installation site are outside your expertise, so caution is necessary.
It is reassuring to have someone knowledgeable about the roof to avoid maintenance and troubles after installation!
Kakeru Koumuten Co., Ltd. is strong in roofing work and can also detach and attach solar panels in-house, allowing for quick responses to maintenance and urgent troubles after solar panel installation!
2.Equipment Specialized in Exterior Renovation
Kakeru Koumuten Co., Ltd. has organized the following warehouses and material storage areas to provide low-cost, high-quality solar and exterior renovation work.
We have established five bases for material storage and showrooms.
In-house Ownership of Scaffolding Materials
To ensure safety during work on the roof, we own the necessary scaffolding materials for temporary scaffolding based on construction conditions, allowing us to assemble scaffolding ourselves.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can also cut costs on scaffolding work.
We have scaffolding materials for approximately 50 single-family homes!
Even if there are height differences on the site, our scaffolding team will plan the scaffolding according to the local conditions.
Storage of materials in our large warehouse
We store roofing materials and paints, and we can also store removed solar panels.
By ordering a large quantity of materials at once, we canpurchase materials at a lower price!
Additionally, we always have a stock of roofing materials, enabling us torespond quickly in emergencies!
Sorting and transporting waste materials in-house
The installation of solar panels often involves roofing work, generating various waste materials such as paint, wood, and metal.
By sorting and recycling waste materials, we can significantly cut waste disposal costs.
Exterior renovation dedicated showroom
In the showroom, not only can you have meetings, but you can also
check the actual foundation brackets for solar panels and see how they are installed on the roofing materials!
It is also possible to simulate the revenue and installation costs when introducing solar panels!
Since roofing and exterior wall work often accompany each other, we also have samples of roofing materials and models that show the structure, allowing for detailed explanations!
3.All Work Performed by Our Own Team
One of Kakeru Koumuten’s major strengths is all work performed by our own team.
By having a consistent system from inquiry to project completion, Kakeru Koumuten can provide high-quality roof renovations at reduced costs.
Additionally, one representative will handle everything from the estimate to project completion.
Since the same person will be in charge, whether it’s sales or construction management, smooth communication is possible.
We can perform consistent in-house work from temporary scaffolding installation to exterior wall painting and roof renovations!
4. Various Permits and Skilled Workers
We have obtained construction industry permits as well as permits for industrial waste collection and transportation!
We also have nationally certified sheet metal and painting technicians, and we are confident in our construction skills.
We are capable of handling large-scale roofing projects such as factories!
5. Warranty and Aftercare
In addition to the manufacturer’s warranty, our solar panel installation work comes with our own workmanship warranty (leakage warranty)!
(The workmanship warranty for solar panel installation is 10 years. Depending on the condition of the roof before installation, we may not be able to provide a warranty unless roof renovation is performed. The workmanship warranty is separate from the manufacturer’s product warranty, and the scope and conditions vary based on the warranty details.)
Aftercare maintenance is available annually, and we send out notification DM each year.
If you have any questions about the warranty, please click on the image above!
6. Flexible and Prompt Response
Our company is equipped to handle various roof troubles and situations.
Even if we cannot access the roof at high altitudes, we can respond using a drone!
During leakage investigations, we can also conduct inspections using a thermal imaging camera.
If the power generation of the solar panels decreases due to dirt, we can also provide cleaning using a specialized brush.
We will respond according to the customer’s wishes.
7. Human Resource Development
To improve skills, we create various roof models and conduct practical training.
Since the construction methods vary depending on the shape and slope of the roof, we regularly conduct skill enhancement education so that each staff member can respond to various cases.
8. Creation of Clear Materials and Simulations
At Kakeru Koumuten, we provide not only “estimates”, “layout diagrams”, and “power generation simulations”, but also a “Solar Installation Guidebook” and a “Profit and Loss Simulation” that takes into account loan interest rates and electricity costs.
The profit and loss simulation can be created for projected cumulative profits and losses over 20 to 30 years.
Even customers who are not familiar with solar installations will find our materials easy to understand, including important points and disadvantages!
We encourage you to obtain comparative estimates and review plans from other companies!
Roof Inspection Before Installing Solar Panels
Once solar panels are installed, they will remain on the roof for 20 to 30 years.
It is crucial to confirm before installation whether it is okay to place them directly on the current roof, as this is the key point to prevent leaks and unnecessary expenses!
Kakeru Koumuten, specializing in roofing work, has compiled the items to check before installation.
| 1. Type of roofing material and age | The fixing method varies depending on the roofing material, such as slate, tiles, metal roofs, or flat roofs (roof waterproofing). If the remaining lifespan of the roofing material is short, we may suggest a roof renovation first. |
| 2. Condition of the substrate and waterproof sheet | If the sheathing or roofing (waterproof sheet) beneath the roofing material is damaged, it can affect the fastening strength and waterproofing. We will also check for signs of leaks. |
| 3. Orientation, slope, and shading of the roof | The orientation and slope of the roof surface, as well as shading from neighboring houses, trees, and utility poles, can affect power generation. We will create a layout diagram based on the drawings and the site, and you can confirm it with the power generation simulation. |
| 4. Shape of the roof and installable area | The number of panels (installation capacity) that can be placed depends on the shape and size of the roof. The number of panels that can be installed varies depending on their size, so we will compare based on the total output of the roof. |
| 5. Fixing method and waterproofing details | We will confirm whether the method involves drilling holes in the roofing material or using brackets to secure it. The fixing method varies by technique, so please check the waterproofing treatment of the fixing parts during the estimate. |
| 6. Weight of the roof | The roof will become heavier due to the panels. After investigating the existing roof, substrate, and load-bearing capacity, switching to lighter roofing materials may be an option if necessary. |
| 7. Location of equipment installation and wiring | We will check the installation locations for the power conditioner and storage battery, as well as the wiring route to the distribution board. The length of the wiring will also affect costs. |
| 8. Ease of scaffolding setup and delivery routes | If there are elevation differences on the site, planning for scaffolding and delivery routes for equipment and materials may require some ingenuity. The width of the front road and any elevation differences on the site will also be checked during the on-site survey. |
Fixing Methods and Verification Points by Roofing Material
| Roofing Material | Main Fixing Method | Verification Points Before Installation |
|---|---|---|
| Slate Roof | Varies by method (e.g., fixing brackets with screws to roofing material and substrate) | Waterproof treatment of fixing parts, cracks or deterioration of slate, condition of the substrate. If deterioration is advanced, consider roof overlay (cover method) or replacement first. |
| Tile Roof | Fixed with brackets and methods suitable for the type of tile (even methods that do not drill holes in the tiles will fix to the substrate) | Type and condition of tiles, substrate, load-bearing capacity. Depending on the investigation results, there may be methods to replace with lighter roofing materials before installation. |
| Metal Roof (Horizontal and Vertical) | Fixed with catch-type brackets that grip the roofing material (depends on the combination of roofing material and brackets) | Whether the roofing material and brackets are compatible, installation conditions from the roofing material manufacturer. If compatible, methods that do not drill holes may be available. |
| Flat Roof / Rooftop | Fixed by installing a framework | Type and deterioration status of the waterproof layer, waterproofing around the framework. Consider in conjunction with the timing of waterproofing work. |
If you perform roof renovations 10 to 20 years after installation, there will be additional costs for removing and reinstalling solar panels. If the roof is deteriorating, renovating to high-durability roofing materials before installation may help reduce costs in the long run.
Kakeru Koumuten Co., Ltd. specializes in roofing work and can also handle the removal and reinstallation of solar panels in-house, so please consult us according to the condition of your roof!
▶ Click here for roof renovations in Akishima City, Tokyo
PossibleSubsidies and Grants in Akishima City, Tokyo
If you are introducing solar panels or storage batteries in Akishima City, Tokyo, there is a possibility that the systems from the “National Government,” “Tokyo Metropolitan Government,” and your residence “Akishima City” may apply.
The following information is based on the official pages of each system as of October 7, 2026. The application status may change depending on the budget, so please check the latest information before contracting or starting work.
Eligibility Conditions and Application Timing for Subsidy Programs
| Program | Main Eligibility Conditions | Subsidy Amount | Application Period & Status |
|---|---|---|---|
| Tokyo “Household Solar Power Generation Promotion Project” | Individuals, corporations, or management associations installing a new unused solar power system (output under 50kW, JET certification, etc.) in residential properties within Tokyo. The generated power must be used in the residential part. Pre-application is required. | Existing homes: 150,000 JPY per kW for 3.75 kW or less (maximum 450,000 JPY), 120,000 JPY per kW for over 3.75 kW up to under 50 kW. New homes: 120,000 JPY per kW for 3.6 kW or less (maximum 360,000 JPY), 100,000 JPY per kW for over 3.6 kW. |
For fiscal year Reiwa 8, pre-applications are being accepted from May 29 (will end once the budget is reached). From the pre-application for fiscal year Reiwa 8, submission of certificates issued by financial institutions during performance reporting is mandatory. |
| Tokyo “Household Storage Battery Promotion Project” | Owners of eligible devices (storage batteries registered with SII, excluding national and local governments). Installation must occur between April 1, Reiwa 8 and March 30, Reiwa 11. If pre-applying after October 1, Reiwa 8, only products registered with the national SII for fiscal year Reiwa 8 are eligible. | Storage battery package: 100,000 JPY per kWh (maximum 1,200,000 JPY per household). Additional incentive for participating in DR demonstration (100,000 JPY per unit; 150,000 JPY per unit if energy management equipment is installed). Expansion of storage battery unit: 60,000 JPY per kWh (maximum 720,000 JPY per household). |
For fiscal year Reiwa 8, pre-applications are being accepted from May 29. Grant applications and performance reports will be accepted from June 30. |
| Akishima City “Subsidy for the Promotion of New Energy Equipment for Residential Use” | Residents of individual homes within the city. Devices installed between January 1, Reiwa 8 and December 31 are eligible, and applications must be made after the installation (post-application). Multiple device applications are not allowed; only one device can be selected. | Solar power generation: 15,000 JPY per kW (maximum 60,000 JPY). Storage battery: 50,000 JPY. |
Applications will be accepted from December 1, Reiwa 8 to January 29, Reiwa 9 (postmarked by January 29). In the past three years, the total application amount exceeded the budget, and the grant amount was determined by allocation. |
| National “DR Household Storage Battery Project” (Reiwa 7 Fiscal Year Supplement) | Newly introducing household storage systems that can be utilized for DR (demand response) with registered products. | Calculated based on an initial effective capacity of 34,500 JPY per kWh (subsidy rate within 3/10, maximum 600,000 JPY per application). | The budget was reached on May 29, 2026, and the public recruitment has ended (the official site states there are no plans to reopen public recruitment, and applications cannot be made at this time). |
| National “Mirai Eco Housing 2026 Project” (Renovation) | Storage batteries are one of the eligible facilities, but they must be combined with essential works such as insulation renovations of windows (openings) and structures; applications cannot be made for just the installation of storage batteries. Solar panels are not included as eligible facilities. | Storage battery: 96,000 JPY per household. | As soon as the budget limit is reached, the program will end. As of October 5, 2026, the application amount for renovations is displayed as 8% of the budget on the official website. Please check the reception status on the official site. |
The Tokyo solar power and storage battery subsidy program requires prior application. For storage batteries applied for after October 1, 2026, only products registered with the national SII will be eligible, and the equipment requirements will change. The subsidy in Akishima City is a post-application system where applications are made after installation, with the application period from December 1, 2026, to January 29, 2027. Each program has different eligibility conditions, application procedures, and whether they can be combined, and applying does not guarantee that subsidies will be granted, so please confirm before contracting and starting work.
Kakeru Koumuten will guide you on the eligibility conditions and application periods for each program after confirming them.
National Subsidy “DR Household Storage Battery Project (Support Project for Introducing Household Storage Battery Systems for DR Resource Implementation)”
The national government has been implementing the “DR Household Storage Battery Project” to support the installation of household storage batteries.
This program targets those who are newly introducing registered storage systems that can be used for demand response (DR), and in the fiscal year 2025 supplementary project, the subsidy amount was determined based on a standard amount of 34,500 JPY per 1 kWh of initial effective capacity, with a subsidy rate of up to 30% and a maximum of 600,000 JPY per application. There are conditions such as that contracts or orders made before the grant decision are not eligible.
However, the fiscal year 2025 supplementary application amount reached the budget on May 29, 2026, and the public recruitment has ended. The official website also states that there are no plans to reopen the public recruitment, and applications cannot be made at this time. Please check the official website for future public recruitment.
Currently, there are no subsidies confirmed for the installation of solar panels on existing homes.
👉 Here is the official website for the DR Household Storage Battery Project
Tokyo “Promotion Project for Introducing Solar Power Generation in Households”
This subsidy is for those who are newly installing unused solar power generation systems in residential homes in Tokyo. The simultaneous installation of storage batteries is not a condition.
● Existing homes: For systems below 3.75 kW, 150,000 JPY per kW (maximum 450,000 JPY), for systems above 3.75 kW and below 50 kW, 120,000 JPY per kW
● New homes: For systems below 3.6 kW, 120,000 JPY per kW (maximum 360,000 JPY), for systems above 3.6 kW and below 50 kW, 100,000 JPY per kW
● There are also additions for the installation of rooftop frames and waterproofing work.
The target is for unused panels that have obtained JET certification and are installed in residential homes in Tokyo with an output of less than 50 kW, used in the living area. The process involves making a prior application and then applying for the grant after installation. From the prior application for the fiscal year 2026, it has become mandatory to submit a certificate issued by a financial institution at the time of performance reporting.
The official page of Tokyo states that pre-registration is being accepted from May 29, Reiwa 8. It will end once the budget is reached, so please check the official page for the status of applications.
👉 Here is the official page of Tokyo (Cool Net Tokyo)
Tokyo’s “Household Battery Installation Promotion Project”
This is a subsidy for the installation costs of battery systems aimed at increasing self-consumption of electricity generated by solar power and improving energy independence during emergencies.
●Battery package: 100,000 JPY per kWh (up to 1,200,000 JPY per household)
●Additional for participating in DR demonstration: 100,000 JPY per unit (150,000 JPY per unit if energy management equipment is installed)
●Expansion of battery units: 60,000 JPY per kWh (up to 720,000 JPY per household)
Eligible applicants are owners of the subsidized equipment (excluding national and local governments), and the installation must be completed between April 1, Reiwa 8 and March 30, Reiwa 11. If pre-registration is done after October 1, Reiwa 8, only products registered in the SII for Reiwa 8 will be eligible.
The official page of Tokyo states that pre-registration is being accepted from May 29, Reiwa 8. For detailed conditions such as combinations with solar power generation, please check the official page.
👉 Here is the official page of Tokyo (Cool Net Tokyo)
Akishima City “Subsidy for the Promotion of New Energy Equipment for Residential Use” (Reiwa 8)
This subsidy is for residents of individual houses in the city who install new energy equipment. The equipment installed between January 1, Reiwa 8 and December 31, Reiwa 8 is eligible, and it is a post-application system where applications are made after the equipment is installed.
●Solar power generation: 15,000 JPY per kW (up to 60,000 JPY)
●Battery: 50,000 JPY
●Only one device can be selected, and multiple applications for different devices are not allowed
The application period is from December 1, Reiwa 8 to January 29, Reiwa 9 (must arrive by January 29 if mailed), as stated on Akishima City’s official page. As of October 7, 2026, applications have not yet started. The official page also mentions that in the past three years, the total amount of applications exceeded the budget, leading to proportional measures.
Conditions for eligible equipment and application methods may change, so those considering applying should check the official page.
👉 Here is the official page of Akishima City
Solar Panel Installation & Battery Installation Price List
⇧Service Menu | For Costs Related to Solar Panel Installation and Battery Installation, Click Here
⇧Service Menu | For Costs Related to Solar Panel Removal and Water Heater Removal, Click Here
Breakdown of Installation Capacity, Equipment, and Construction Costs
The costs for solar panels and batteries should be confirmed by separating them into “Equipment Costs (Device Costs)” and “Construction Costs”.
Even for the same “Complete Solar Panel Installation,” the amount can vary significantly depending on the installation capacity, equipment grade, and roof condition.
Understanding Installation Capacity (kW) and Battery Capacity (kWh)
The installation capacity of solar panels is determined by “Output of One Panel (W) × Number of Panels”, with the unit being kW (kilowatt). Batteries are compared based on the amount of electricity they can store, represented in kWh (kilowatt-hour).
The amount of kW that can be placed on the roof varies for each house based on the roof’s shape, orientation, and size. At Kakeru Koumuten, we create layout diagrams from blueprints and on-site surveys to present the installation capacity.
On our pricing page, we list solar panels as approximately 800,000 JPY to 1,200,000 JPY for 3 to 5 kW, and 1,200,000 JPY to 1,900,000 JPY for 6 to 10 kW. (These are just estimated amounts and may vary based on factors such as wiring length, scaffold range, existing roofing materials, and panel layout.)
▶ Installation Menu | Costs for Solar Panel Installation and Battery Installation
Items to Check in the Quotation (Cost Verification)
When comparing quotes, it’s common to compare different capacities and equipment. Please check if the following items are clearly stated in each company’s quotation!
| 1. Solar Panels | Manufacturer, model number, output per panel (W), number of panels, and total installation capacity (kW) are listed. |
| 2. Power Conditioner | Manufacturer, model number, capacity, number of units, installation location (indoor/outdoor). Also check if it is a type that controls the battery together. |
| 3. Battery | Manufacturer, model number, capacity (kWh), range available during power outages (whole house or specific circuits), installation location. |
| 4. Mounting Frame and Hardware | Name of the hardware suitable for the roofing material and the fixing method (whether it is a method that drills holes or a method that clamps and fixes). |
| 5. Wiring and Electrical Work | Wiring route and length, work around the distribution board, and whether there is a monitor to check the power generation amount. |
| 6. Roof Reinforcement and Waterproofing | Details of waterproofing treatment at the fixing points, whether necessary roof repairs and substrate reinforcements are included. |
| 7. Applications | How much support is included for applications to the power company, certification applications for selling electricity (FIT), and subsidy applications. |
| 8. Scaffolding | Range and quantity of scaffolding. If it is simultaneous with roof work or exterior painting, check that the same range and quantity are not double counted. |
| 9. Removal and Disposal | Whether the removal of existing solar thermal water heaters or old panels and disposal costs for waste materials are included. |
| 10. Tax Classification and Warranty | Whether it is tax-inclusive or tax-exclusive, conditions under which additional costs may arise, and details and duration of manufacturer and workmanship warranties. |
If the capacities differ, the amounts and power generation will also change. Kakeru Koumuten Co., Ltd. welcome comparisons, so if you bring in quotes from other companies, we can explain the differences item by item!
Self-Quotation and Profit and Loss Simulator for Solar Power Generation
With the simulator above,
you can get an estimated quote and a financial simulation for up to 30 years!
If you know the total installation capacity of solar panels on the roof and the capacity of the storage battery, you can obtain an estimated quote and financial simulation!
*The simulation results are estimates. Actual financial results may vary based on assumptions such as electricity rates, self-consumption ratios, selling prices, and costs for equipment inspection or replacement.
Customer Feedback
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customer reviews
Asao-ku, Kawasaki City | We received reviews about the ridge cap and rain gutter replacement work!
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customer reviews
Kohoku-ku, Yokohama | We received reviews about the roof overlay (cover method)!
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customer reviews
Kohoku-ku, Yokohama | We Received Reviews About Exterior Painting!
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customer reviews
Hodogaya-ku, Yokohama | We received reviews about our exterior fence construction!
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customer reviews
Tsurumi-ku, Yokohama | We received reviews about roof and exterior wall painting, as well as metalwork and rain gutter replacement work!
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customer reviews
Higashiyamato City, Tokyo | We received reviews about exterior painting and roof overlay (cover method)!
Case Studies of Solar Panel Installation
| Construction Details |
| Solar Panel Installation Battery Installation |
| Existing Roofing Material |
| Horizontal Metal Roof (Super Galtect) |
| Installation Capacity |
| Solar Panel: 4.3kW Battery: 5kWh |
| Base Mounting Hardware Used |
| Niigata Manufactured / Aluminum Catch Type Hardware |
| Fixing Method & Waterproofing Arrangement |
| Fixed using catch type hardware gripping the horizontal metal roof (Catch Method) |
| Price Range |
| 2,200,000 JPY～2,300,000 JPY *Due to the grant being provided, the actual burden amount is approximately 1,000,000 JPY Estimated recovery period for construction costs: about 8 to 9 years (self-consumption) *The grant amount and recovery estimate are based on the system and calculations at the time of construction and may differ under the current system. |
| Construction Period |
| About 3 days |
| Completion Month |
| April 2025 |
| Inquiry Details |
| I am considering the introduction of solar panels and storage batteries. I heard that grants are available, and I would like to know how much will be provided. |
Our Proposal
We visited to provide an estimate and created a layout diagram for the solar panels from the drawings!
The layout diagram shows the arrangement of solar panels when placed on the roof.
Since we can also determine the installation capacity, it allows for power generation simulations and financial simulations.
We have also understood the expected amount of the grant, so we explained it to the customer along with the estimate!
How to Choose a Solar Panel Installation Contractor in Akishima City, Tokyo
There are many solar panel installation contractors available in Akishima City, Tokyo, and you may be unsure which contractor to choose.
Therefore, when requesting solar panel installation and battery storage installation work, make sure to check the following 4 points:
● Ensure they have extensive knowledge not only about solar panels but also about roofs
● Confirm the presence of warranties and aftercare services
● Obtain estimates from multiple contractors (3 companies is a guideline)
● Check if they provide support for subsidy applications
By confirming the above 4 points, you will be able to choose a reliable contractor.
Knowledge about roofs as well as solar panels
Defective installation of solar panels can sometimes be caused by a lack of knowledge and verification regarding roofs and waterproofing.
While knowledge about solar panels is certainly important, understanding the roof and waterproofing at the installation site of the solar panels is also crucial.
⚠︎Examples of troubles caused by insufficient checks on roofs and waterproofing
・Solar panels were installed on a severely deteriorated roof, leading to leaks
・Solar panels were installed on a roof with a short lifespan, necessitating a renovation for removal and reinstallation within a few years
・Incorrect processing due to misjudgment of the type of waterproofing, resulting in leaks
and more
When installing solar panels, understanding the condition and type of the existing roof allows you to avoid unnecessary expenses and unforeseen troubles.
▶ Go to “Roof Check Before Installing Solar Panels” in this article
Confirm the presence of warranties and aftercare services
When choosing a solar installation contractor, make sure to check for warranties. It is important to verify not only the duration of the warranty but also the coverage, exclusions, and cost conditions.
While the solar panels and battery storage units come with manufacturer warranties, also check for the presence of installation warranties in case leaks occur after installation!
For contractors that offer installation warranties, if leaks occur after installation, they may be covered under the warranty as long as it falls within the warranty period and conditions.
Additionally, some contractors provide aftercare services separate from warranties, so make sure to check if the contractor you are considering has aftercare services.
Since abnormalities or damage on the roof can be in hidden areas, you may not notice them yourself.
By conducting inspections of hidden areas through aftercare maintenance, you can more easily detect abnormalities early and prevent major repairs or failures!
At Kakeru Koumuten Co., Ltd., the installation of solar panels comes with a leak warranty as part of the workmanship warranty. (The warranty for solar panel installation is 10 years, and depending on the condition of the roof before installation, we may not be able to provide a warranty unless roof renovations are performed.)
We also provide aftercare maintenance and send out annual DM!
After checking the DM, if you wish, we will visit for aftercare maintenance!
Obtain estimates from multiple contractors (3 companies as a guideline)
When requesting the installation of solar panels, let’s obtain estimates from multiple contractors.
Even for the same manufacturer and the same construction content, costs may vary, and warranties and after-sales services may differ.
Additionally, obtaining multiple estimates makes it easier to negotiate prices.
To request your preferred contractor at a lower price, we recommend obtaining estimates from multiple contractors.
When comparing estimates, please check:
“Check the estimate items”
“Type of solar panels”
“Warranties and after-sales services”
and make a detailed comparison! If the rank of auxiliary materials is low or if processes are skipped, costs can be reduced, so avoid judging solely based on price!
▶ To “Breakdown of installation capacity, equipment, and construction costs” in this article
Check if they provide support for subsidy applications
There may be subsidies available for the installation of solar panels and storage batteries, but if the order of procedures is incorrect or if there are deficiencies in the documents, the grant may not be awarded.
Since there are systems like the Tokyo subsidy that require prior application, it is reassuring to have a contractor who supports the preparation of necessary documents and the flow of procedures.
Complete the procedures specified for each system (for the Tokyo subsidy, prior application is required) before proceeding with the construction!
In the case of the Tokyo subsidy, after installation, you will need to submit a grant application and performance report, which will be reviewed before the grant is awarded! (The flow of procedures varies by system)
▶ To “Subsidies and grants that may be applicable in Akishima City, Tokyo” in this article
Benefits of Introducing Solar Equipment
The benefits of introducing solar panels are as follows!
Benefit 1: Economic Benefits
The biggest advantage of introducing solar panels is the economic benefit!
The selling price of electricity has decreased compared to ten years ago, but by consuming the generated electricity, you can reduce the amount of electricity purchased from the utility company and gain benefits!
As electricity prices rise, the ability to cover your consumption with solar power becomes attractive!
If you plan to use the generated electricity at night, installing a storage battery is essential!
Furthermore, the selling price (FIT) for residential use (under 10kW) will be set at “24 yen/kWh for the first four years, and 8.3 yen/kWh from the fifth to the tenth year” for certifications after October 2025, and the same price will apply for the 2026 fiscal year. After the fifth year, it is often more advantageous to use it in your home (self-consumption) rather than selling it, making the combination with a storage battery a viable option.
👉 Ministry of the Environment, Trade and Industry | For purchase prices and periods, click here
Advantage 2 Subsidies can be utilized!
The conditions and amounts of subsidies vary by prefecture and municipality, but if you meet the conditions, you may be able to utilize subsidies!
The reduction of the actual burden due to subsidies is a significant advantage!
In the case of Akishima City, there is a possibility of being eligible for the programs of the national government, Tokyo, and Akishima City. The subsidy application for Akishima City is a post-application after installation, and the application period is from December 1, Reiwa 8 (2026) to January 29, Reiwa 9 (2027) (please check the application status for each program).
Advantage 3 Environmentally friendly!
Solar power generation has low carbon dioxide emissions and can reduce dependence on fossil fuels, contributing to the mitigation of global warming.
Solar panels themselves do not produce noise or exhaust gases during the generation process, making them an environmentally friendly method of power generation. (However, devices such as power conditioners may have operational noise.)
Advantage 4 Heat insulation effects are expected!!
By installing the panels on the roof or rooftop, they block direct sunlight from hitting the roof.
Especially in summer, this can help reduce the roof temperature, providing expected heat insulation effects!
(Note that this does not improve the building’s insulation performance itself.)
Benefit 5: Electricity can be used even during power outages!!
If a storage battery is installed, it becomes possible to use electricity even during emergencies such as power outages!
Even without a storage battery, if you have a power conditioner with autonomous operation capability, you may be able to use electricity from a dedicated outlet during the daytime when generating power.
(Note that the devices, output, and duration that can be used during a power outage vary depending on the model and wiring method.)
What points should be noted when introducing solar power generation?
Next, we will explain the “three points to note” when installing solar panels!
Point 1: Maintenance costs can be incurred
A particularly overlooked maintenance cost is for the roof where the solar panels are installed.
If you perform roof renovations 10 to 20 years later, there will be costs for removing and reattaching the solar panels.
If the existing roof is deteriorating, it is reassuring to renovate it with durable roofing materials before installing the solar panels!
Additionally, there will be costs for regular inspections of the equipment, repairs or replacements of the power conditioner, and updates due to the deterioration of the storage battery.
It would be reassuring to request a simulation that considers maintenance costs before introducing solar panels!
Point 2: The risk of leaks increases depending on the roofing material
The fixing methods for slate roofs and tile roofs vary by construction method, but when using screws or other fasteners to secure the roofing material and substrate, waterproofing of the fixed areas becomes crucial.
If the method involves making holes in the roof, the risk of leaks inevitably arises.
Of course, we will ensure proper waterproofing, but if you are concerned about making holes, one option is to replace the roofing material with a metal roof and secure the solar panels using the catch method. (The catch method has compatibility conditions between the roofing material and the fasteners, and it cannot be used with all metal roofs.)
Foundation Brackets for Horizontal Metal Roofs
Note 3: The Roof Becomes Heavier
Since solar panels will be installed, the roof will become heavier. After investigating the existing roof, substrate, and load capacity, replacing it with a lighter roof may also be an option if necessary.
How to Choose Solar Panels?
There are many manufacturers of solar panels, and their output and costs vary.
It is not simply a matter of “This manufacturer has the best solar panels”; it is important to choose solar panels that are suitable for your life plan and building!
Here are some points to consider when comparing solar panels!
How to Choose 1: Compare Based on Total Roof Output
When installing solar panels on the roof, it is important to know how much electricity can be generated in a limited area, and generating more electricity is always better!
Solar panels come in various sizes and outputs depending on the manufacturer.
If you have a 350W output panel and a 400W output panel, at first glance, the panel with the higher output may seem better.
However, if the size of the panel does not fit well on the roof, there may be cases where “20 panels of 350W can be installed” and “15 panels of 400W can be installed,” leading to different numbers of panels that can be installed on the same roof due to size differences.
400W×15 panels = 6kW (Total roof output)
350W×20 panels = 7kW (Total roof output)
As shown above, even if the output of a single panel is lower, the total output of the roof may be higher!
It is important to consider the total output of the roof rather than the output of a single panel!
*The above calculations are for total output (kW). The actual electricity generation (kWh) will vary depending on conditions such as roof orientation, slope, and shading.
How to Choose 2: Compare Based on Degradation Rate of Solar Panels
Solar panels have a degradation rate, and their output gradually decreases after 10 years and 20 years.
The degree of output reduction after long-term use varies by product. The manufacturer’s output guarantee value is a standard figure for warranty purposes and does not indicate the actual degradation rate or electricity generation itself.
By considering the degradation rate along with the initial output, you can choose solar panels without regrets!
How to Choose 3: Compare Based on Warranty Period
There are several types of warranties for solar panels, including “output warranty,” “natural disaster warranty,” and “system warranty,” and the warranty periods vary by manufacturer.
For output warranties, some manufacturers offer a 30-year warranty, while others provide a 10-year warranty, so it varies widely!
A longer warranty is always better, so let’s check the warranty periods and conditions of the manufacturers you are considering!
Frequently Asked Questions about Solar Panel and Storage Battery Installation in Akishima City, Tokyo
We have compiled frequently asked questions from customers considering the installation of solar panels and storage batteries in Akishima City, Tokyo. (Tap to open the answers)
How much does it cost to install solar panels and storage batteries in Akishima City, Tokyo?
The cost varies depending on the installation capacity, equipment, and roof condition. In the above construction example (solar panel 4.3kW + storage battery, completed in April 2025), it was 2.2 million yen to 2.3 million yen.
Guidelines for different capacities are available on the solar panel installation and storage battery installation pricing page. We will create a layout diagram based on the drawings and site survey and provide a free estimate!
Are there any subsidies available for solar panel and storage battery installation in Akishima City, Tokyo?
As of October 7, 2026, Tokyo’s “Promotion Project for Solar Power Generation in Households” (for existing homes, 15,000 yen per kW for up to 45,000 yen for 3.75kW or less) and “Promotion Project for Storage Battery Installation in Households” (100,000 yen per kWh for up to 1.2 million yen per household) are accepting pre-applications starting May 29, 2026, as listed on the official Tokyo (Cool Net Tokyo) page. Akishima City offers a subsidy for the promotion of new energy equipment for residential use (15,000 yen per kW for solar power up to 60,000 yen, and 50,000 yen for storage batteries), which can be applied for after installation from December 1, 2026, to January 29, 2027, as stated on Akishima City’s official page. The national DR household storage battery project has ended its public recruitment.
Since the application status may change, please refer to the subsidy and grant section and consult us before signing a contract.
Can I apply for subsidies after the construction is completed?
This depends on the system. Tokyo’s subsidies require pre-application, while Akishima City’s grants are a post-application system after installation. Conditions such as whether you can contract and start construction before applying vary by system, so please confirm before signing a contract.
The order of procedures varies by system, so please check before signing a contract and starting construction.
Can solar panels be installed on slate roofs? I’m worried about leaks.
It is possible to install on slate roofs, but it is necessary to check the condition of the roofing material and substrate. The fixing method varies by construction method, and for methods that fix hardware to the roofing material or substrate, waterproofing treatment of the fixed parts is essential.
Kakeru Koumuten Co., Ltd. is a specialized exterior renovation company strong in roofing work, so we will check the condition of the roof before installation. If deterioration is progressing, we can also propose methods such as roof overlay (cover method) or complete replacement before installation.
My roof is old. Should I do a roof renovation first?
It depends on the condition of the roof. If a roof renovation is needed within 10 to 20 years after installation, there will be additional costs for removing and reinstalling solar panels. If the remaining lifespan of the roof is short, renovating to a highly durable roofing material before installation may help reduce the total costs.
Please consult us about the installation process after checking the condition of the roof during the on-site survey!
Should I install a storage battery together with the solar panels?
If you want to use the generated electricity at night or prepare for power outages, simultaneous installation is recommended. The selling price for electricity will be 8.3 yen/kWh after the fifth year, making it more beneficial to use it in your home rather than selling it.
Additionally, the subsidy for storage batteries in Tokyo (for Reiwa 8, it is 100,000 yen per kWh, with a maximum of 1,200,000 yen per household) aims to increase self-consumption of electricity generated by solar power. In Akishima City, storage batteries are also included in the subsidy (multiple device applications are not allowed, and only one device can be selected). You can compare “solar power only” and “solar power + storage battery” through a financial simulation.
How many kW can be installed on my roof? Is it okay for north-facing or shaded roofs?
The capacity that can be installed varies depending on the shape, orientation, and size of the roof. At Kakeru Koumuten, we create a layout diagram from the drawings and on-site survey, and we will provide you with the installation capacity and power generation simulation.
Akishima City gently slopes from the northwest to the southeast towards the Tama River, with the northern side being the Musashino Plateau and the area along the Tama River being alluvial plains. The shape, orientation of the roof, and the shading from surrounding buildings vary for each house, affecting the installable capacity. You can check the expected power generation through the power generation simulation.
How long will the construction period be?
For the above construction example (4.3 kW solar panels + storage battery), it took about 3 days. The duration may vary if roofing work is done simultaneously or depending on the shape of the roof and installation capacity.
Additionally, there will be a separate period for applying for subsidies and to the power company, so please consult us as soon as possible.
What is the current selling price (FIT)?
For residential use (under 10 kW), the selling price for certifications after October 2025 will be 24 yen/kWh for the first 4 years, and 8.3 yen/kWh from the 5th to the 10th year, and the same price will apply for the 2026 fiscal year.
The idea is to recover initial costs more quickly in the first 4 years and then focus on self-consumption. Kakeru Koumuten provides a financial simulation that takes into account loan interest rates and electricity costs.
Can you take care of maintenance and inspections after installation?
Yes, we can. Kakeru Koumuten sends out annual after-service maintenance notices via DM, and we visit customers who wish to have inspections. We can also provide cleaning of solar panels using a special brush if the power generation decreases due to dirt.
The roof is a place that is difficult to check by yourself, so if you have any concerns, please feel free to consult us.
Can you also handle renovations for roofs that already have solar panels installed?
Yes, it is possible. Kakeru Koumuten Co., Ltd. can detach and reattach solar panels in-house, allowing us to remove the panels, perform roof overlay (cover method) or re-roofing, and then reinstall them consistently. The removed panels can be stored in our own warehouse.
For costs, please refer to the solar panel removal and water heater removal pricing page.
If you are looking for a solar panel installation company in Akishima City, Tokyo, please consult Kakeru Koumuten
Our company handles a wide range of exterior renovations, including solar panel installations, roof work, and exterior wall work in Akishima City, Tokyo.
We have received requests from many customers, including renovation companies and real estate agencies, who have contacted us!
Kakeru Koumuten promises “high-quality renovations at low cost”, and we have received positive feedback from many customers.
We continue to update our construction performance every year, and we will strive to improve quality to satisfy even more customers in the future.
Our company can perform all exterior renovations, not only roof overlay work and re-roofing but also partial roof repairs, exterior painting, and exterior wall cover methods.
We are also happy to handle small jobs such as partial repairs and rain gutter cleaning!
In urgent cases such as leak repairs, we may be able to provide emergency measures without setting up scaffolding, as long as safety can be ensured, so please consult us!
“I want to know about recommended solar panels”, “I want to keep costs down as much as possible”, “I just want an estimate for now”, we will provide the best solutions for your specific requests.
We will never propose unnecessary work that prioritizes profit!
We always stand in the customer’s position and propose the best construction plan!
We are confident that we will not be outdone in terms of cost, quality, and organization compared to other companies in exterior work!
We welcome competitive estimates with confidence!
Estimates are completely free, and if our company is found to be inferior to others, you are free to decline!
Characteristics of Akishima City, Tokyo and Points of Solar Work
Akishima City is located approximately 35 kilometers west of the city center, almost in the center of Tokyo, with an area of 17.34 square kilometers. There is a gentle slope from the northwest to the southeast towards the Tama River, with the riverbank being an alluvial plain and the northern side being the Musashino Plateau. We have summarized the characteristics of the terrain in Akishima City, Tokyo, and points to consider when installing solar panels and storage batteries below. (Tap to open)
View the characteristics of Akishima City, Tokyo, and points for solar installation
■ Gently sloping terrain. Check the elevation differences and delivery routes for each site
The elevation in the city is reported to be approximately 170.72 meters at the highest point in Haijima Town, 6-chome, and approximately 76.68 meters at the lowest point in Goji Town, 3-chome (excluding river areas). While the city as a whole has a gentle slope, the elevation differences and the width of the front road vary by site, so the method of scaffolding and the delivery routes for panels and storage batteries will be confirmed on-site. At Kakeru Koumuten, our own scaffolding team plans the scaffolding according to the site, creates layout diagrams from the drawings and on-site surveys, and you can check the power generation simulation.
■ Check the flood and internal water hazard maps. Be cautious about the installation location of equipment
The flood and landslide hazard map of Akishima City shows the areas expected to be inundated in the event of flooding from rivers such as the Tama River. Additionally, the internal water hazard map assumes a maximum rainfall of 153 millimeters in one hour and a total rainfall of 690 millimeters over 24 hours, targeting flooding caused by rainfall exceeding the drainage capacity of the sewer system. The impact of flooding may vary depending on where the power conditioner and storage battery are installed, separate from the panels on the roof. Please check the assumptions for your residence using the city’s hazard map and consult with us about the installation location and height in conjunction with the installation conditions of the manufacturer you are using.
■ Roof types and ages vary from house to house. Check the roof and waterproofing before installation
Even within the same city, the types of roofs, ages, and shapes of the sites vary from house to house. The capacity that can be installed and the fixing methods also change depending on the shape and orientation of the roof and the materials used. At Kakeru Koumuten, we will check the type and condition of the roof and the situation of the site before installation, and propose fixing methods, waterproofing arrangements, and scaffolding plans.
■ The annual sunshine duration at the Tokyo Observatory is approximately 1,927 hours
According to the Japan Meteorological Agency’s average values (1991-2020), the annual sunshine duration at the Tokyo Observatory is approximately 1,927 hours, with January (approximately 193 hours) being the most and June during the rainy season (approximately 124 hours) being the least. (This is a reference value, not an observation value within Akishima City.)
The power generation amount in Akishima City can also be affected by shadows from surrounding buildings and trees, so conducting an annual power generation simulation and selecting the capacity of the storage battery to match the times of high electricity usage are key points.
Our company handles many exterior construction and solar power projects in Akishima City, Tokyo.
We are happy to assist with partial roof repairs such as roof overlay work, roof replacement, and leak repairs, as well as other repairs! Please feel free to consult us about any sudden troubles!
Service Area in Akishima City, Tokyo
Kakeru Koumuten Co., Ltd. accepts requests throughout Kanagawa Prefecture and all of Tokyo.
List of Areas in Akishima City, Tokyo
Asahicho, Akishima City / Higashimachi, Akishima City / Oogamimachi, Akishima City / Gouchimachi, Akishima City / Kamikawaharacho, Akishima City / Showamachi, Akishima City / Tanakamachi, Akishima City / Tamagawamachi, Akishima City / Tsukijimachi, Akishima City / Tsutsujigaoka, Akishima City / Nakagami, Akishima City / Haijimamachi, Akishima City / Fukushima, Akishima City / Matsubaramachi, Akishima City / Midorimachi, Akishima City / Mibori, Akishima City / Miyazawamachi, Akishima City / Musashino, Akishima City / Mokuseinomori, Akishima City
・Exterior wall painting in Akishima City, Tokyo, is entrusted to Kakeru Koumuten Co., Ltd.!
・Roof renovation in Akishima City, Tokyo, is entrusted to Kakeru Koumuten Co., Ltd.!
・Exterior renovation in Akishima City, Tokyo, is entrusted to Kakeru Koumuten Co., Ltd.!
・Kakeru Koumuten Co., Ltd. construction achievements
・Kakeru Koumuten Co., Ltd. after maintenance
・Kakeru Koumuten Co., Ltd. construction menu and price list
・Kakeru Koumuten Co., Ltd. staff blog and announcements
・Explaining the importance of comparative estimates and key points!
・12 major manufacturers of solar power generation! Introducing features and selection points!
・What are the installation costs for solar power generation? Thoroughly explaining tips to reduce costs!
・What are the suitable locations for installing solar power generation? Introducing key points for site selection!
・Here is the introduction to solar power generation estimates!
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contact Kakeru Koumuten Co., Ltd.
Kakeru Koumuten is a young company whose team is, on average, in their late twenties, but our skills are second to none.
Our greatest strength is that we handle scaffolding, roofing and painting entirely in-house. In an industry where these tasks are usually divided among contractors, our complete service simplifies project management and helps keep costs down. Above all, if a problem arises, we respond promptly.
We proudly describe ourselves as the youngest and most helpful renovation company in Kanagawa!
