Leave the installation of solar panels in Ome City, Tokyo to Kakeru Koumuten Co., Ltd.!
For solar panel and battery installation in
Ome City, Tokyo,
trust Kakeru Koumuten!
Kakeru Koumuten is a company specializing in exterior renovations.
As a company strong in roofing work, we are entrusted with solar panel and battery installation considering roofing and waterproofing!
“How to Choose a Solar Panel Contractor in Ome City, Tokyo”
“Costs for Solar Panel and Battery Installation”
“Subsidies Available for Solar System Installation in Ome City, Tokyo”
We will also explain the above three points!
Installing solar panels carries risks, such as “the occurrence of leaks” and other troubles.
To ensure a satisfactory solar panel installation, we recommend obtaining estimates from about three companies!
Table of Contents (tap to open/close)
- Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Ome City, Tokyo
- Roof Inspection Before Installing Solar Panels
- Possible Subsidies and Grants Available in Ome 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 Ome 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 Ome City, Tokyo
- If You Are Looking for a Solar Panel Installation Contractor in Ome City, Tokyo, Contact Kakeru Koumuten
- Characteristics of Ome City, Tokyo and Points for Solar Installation
- Service Area in Ome City, Tokyo
Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Ome City, Tokyo
Regarding why our company is entrusted with solar panel installation by customers in Ome City, Tokyo,
we have unique strengths in solar panel installation that cannot be imitated by other companies,
which have received high praise from many customers.
so 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!
Problems such as leaks caused by the installation of solar panels may arise due to insufficient checks on the roof and waterproofing at the installation site.
Even if one is knowledgeable about solar panels, there are cases where the roof and waterproofing at the installation site are outside their expertise, so caution is necessary.
It is reassuring to have expertise in roofing to avoid maintenance issues 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.Facilities Specialized in Exterior Renovation
Kakeru Koumuten Co., Ltd. has organized the following warehouses and material storage areas to provide solar work and exterior renovations at low cost and high quality.
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 scaffolding materials necessary for temporary scaffolding based on construction conditions, allowing us to set up scaffolding in-house.
By performing scaffolding work with our own scaffolding team instead of outsourcing, we can also cut costs related to scaffolding work.
We own scaffolding materials for approximately 50 single-family homes!
Even in cases where there are height differences on the site, our in-house 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, you canpurchase materials at a lower cost!
Additionally, we always have roofing materials in stock, allowing 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 paints, 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 hold meetings, but you can also
check the actual foundation brackets for solar panels and see how they are attached to the roofing materials!
We can also provide simulations of the revenue and installation costs if you decide to implement solar panels!
Since roofing and exterior wall work often accompany renovations, we also have samples of roofing materials and models that explain the structure, allowing us to provide detailed explanations!
3.All Work Performed by Our Own Team
One of Kakeru Koumuten’s major strengths is its complete in-house construction.
By having a consistent system from inquiry to project completion, Kakeru Koumuten can keep costs down while providing high-quality roof renovations.
Additionally, one representative will handle everything from the estimate to project completion.
Since the same person will manage the sales and construction aspects, smooth communication is possible.
We can provide consistent in-house construction from temporary scaffolding installation, exterior wall painting, to roof renovations!
4. Various Permits and Skilled Workers
We have obtained construction industry licenses and permits for industrial waste collection and transportation!
We also have nationally certified sheet metal and painting technicians on staff, giving us confidence in our construction techniques.
We are capable of handling large-scale roofing projects such as factories!
5. Warranty and Aftercare
In addition to the manufacturer’s warranty for solar panel installation, we also provide our own construction warranty (leak warranty)!
(The construction warranty for solar panel installation is 10 years. Depending on the condition of the roof before installation, a roof renovation may be required to provide the warranty. The construction warranty is separate from the manufacturer’s product warranty, and the coverage and conditions vary based on the warranty details.)
Aftercare is available annually, and we send out notification DM each year.
If you have questions about the warranty, please click on the image above!
6. Flexible and Prompt Response
Our company is equipped to handle various roofing troubles and situations.
If you cannot access the roof at high altitudes, we can utilize drones to assist!
During leak 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 services with specialized brushes.
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 provide technical training to ensure that all staff can handle various cases.
8. Creation of Easy-to-Understand Materials and Simulations
Kakeru Koumuten provides not only “estimates,” “layout diagrams,” and “power generation simulations” but also a “solar construction guidebook” and “profit and loss simulations” that take 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 construction will receive materials that clearly summarize important points and drawbacks!
We encourage you to obtain comparative estimates and compare them with other companies’ plans!
Roof Inspection Before Installing Solar Panels
Once solar panels are installed, they will remain on the roof for 20 or 30 years.
Confirming “Is it okay to install them directly on the current roof?” before installation is the key point to prevent leaks and unnecessary expenses!
Kakeru Koumuten, which specializes in roofing work, has summarized the items to check before installation.
| 1. Types of Roofing Materials and Age | The fixing method varies depending on the roofing material, such as slate, tiles, metal roofs, and 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) under the roofing material is damaged, it can affect the fastening strength and waterproofing. We will also check for any signs of leaks. |
| 3. Orientation, Slope, and Shadows of the Roof | The orientation and slope of the roof surface, as well as shadows from neighboring houses, trees, and utility poles, can affect the power generation. We will create a layout diagram from the drawings and the site, and you can confirm it with a power generation simulation. |
| 4. Shape of the Roof and Usable Area | The number of panels that can be installed (installation capacity) is determined by the shape and size of the roof. The number of panels that can be installed varies depending on the panel size, so we will compare based on the overall output of the roof. |
| 5. Fixing Method and Waterproofing Details | We will check whether the method involves drilling holes in the roofing material for fastening or using brackets to secure the roofing material. The fixing method varies depending on the technique, so please confirm the waterproofing treatment method for the fixed parts during the estimate. |
| 6. Weight of the Roof | The roof will become heavier due to the panels being installed. After investigating the existing roof, substrate, and load-bearing capacity, switching to lighter roofing materials may also be an option if necessary. |
| 7. Installation Location of Equipment and Wiring | We will confirm 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 the cost. |
| 8. Ease of Scaffolding Setup and Delivery Routes | If there are elevation differences on the site, planning for scaffolding and the delivery routes for equipment and materials may require some ingenuity. The width of the front road and any steps on the site will also be checked during the site survey. |
Fixing Methods and Checkpoints by Roofing Material
| Roof Material | Main Fixing Method | Pre-Installation Check Points |
|---|---|---|
| Slate Roof | Varies by method (e.g., fixing brackets to the roof material and substrate with screws) | 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 suited to 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 roof material (depends on the combination of roof material and brackets) | Whether the roof material and brackets are compatible, installation conditions from the roof 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, additional costs for removing and reinstalling solar panels will apply. If the roof is deteriorating, renovating to a highly durable roofing material 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, so please consult us according to the condition of your roof!
▶ Click here for roof renovations in Ome City, Tokyo
Possible Subsidies and Grants in Ome City, Tokyo
If you are introducing solar panels or storage batteries in Ome City, Tokyo, there is a possibility that the systems from the “National Government,” “Tokyo Metropolitan Government,” and your local “Ome 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 “Home 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 for residential purposes. Pre-application is required | Existing homes: 15,000 JPY per kW for up to 3.75 kW (maximum 450,000 JPY), 12,000 JPY per kW for over 3.75 kW to under 50 kW New homes: 12,000 JPY per kW for up to 3.6 kW (maximum 360,000 JPY), 10,000 JPY per kW for over 3.6 kW |
For the fiscal year 2026, pre-applications are being accepted from May 29 (will end once the budget is reached). From the pre-application for fiscal year 2026, submission of proof issued by financial institutions will be mandatory at the time of performance reporting |
| Tokyo “Home Battery Installation Promotion Project” | Owners of eligible devices (batteries registered with SII, excluding national and local governments). Must be installed between April 1, 2026, and March 30, 2027. If applying after October 1, 2026, only products registered with the national SII for fiscal year 2026 are eligible | Battery package: 100,000 JPY per kWh (maximum 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 devices are installed) Expansion of battery units: 60,000 JPY per kWh (maximum 720,000 JPY per household) |
For the fiscal year 2026, pre-applications are being accepted from May 29. Grant applications and performance reports will be accepted from June 30 |
| Oume City “Residential Energy-Saving Equipment Promotion Subsidy Program” | Homeowners who are registered residents in the city and reside in their own homes (must not have any tax arrears). Solar power generation equipment (1 kW or more) and batteries (connected to solar power) installed after April 1, 2025, are eligible, and applications must be made after installation | Solar power generation: 15,000 JPY per kW (maximum 60,000 JPY) Batteries: 5,000 JPY per kWh (maximum 30,000 JPY) High-insulation windows: 50,000 JPY or half of the personal burden amount, whichever is lower |
For the fiscal year 2026, applications have closed as the budget limit has been reached (applications started on May 7, 2026). Future plans are not posted on the city’s official page |
| National “DR Home Battery Project” (Fiscal Year 2025 Supplement) | Newly installed home battery 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 30% and maximum 600,000 JPY per application) | As of May 29, 2026, the budget has been reached, and the public recruitment has ended (the official site states there are no plans to reopen public recruitment, and applications are currently not possible) |
| National “Mirai Eco Housing 2026 Project” (Renovation) | Batteries are one of the eligible devices, but they must be combined with essential works such as insulation renovations of windows (openings) and structures; applications cannot be made for battery installation alone. Solar panels are not included as eligible devices | Batteries: 96,000 JPY per household | Budget will end once the limit is reached. 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 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 Ome City is a post-application system where applications are made after the installation of equipment, and the budget limit for fiscal year 2026 has been reached, ending reception. Eligibility conditions, application procedures, and the possibility of combining different systems vary by program, and applying does not guarantee funding, so please confirm before contracting or starting work.
Kakeru Koumuten will guide you on the eligibility conditions and application periods for each program after confirming them.
National Subsidy “DR Home Storage Battery Project (Support Project for the Introduction of Home Storage Systems for DR Resource Implementation)”
The national government has been implementing the “DR Home Storage Battery Project” to support the installation of home storage batteries.
This program targets those who are newly introducing registered storage systems that can be utilized 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 yen per initial effective capacity of 1 kWh, with a subsidy rate of up to 30% and a maximum of 600,000 yen per application. There are conditions such as that items contracted or ordered 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 offering has ended. The official site also states that there are no plans to resume the public offering, and applications cannot be made at this time. Please check the official site for future public offerings.
Additionally, there are currently no subsidies confirmed for the installation of solar panels on existing homes.
👉 Click here for the DR Home Storage Battery Project official site
Tokyo “Promotion Project for the Introduction of Solar Power Generation in Homes”
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 requirement.
● Existing homes: For systems under 3.75 kW, 150,000 yen per kW (maximum 450,000 yen); for systems over 3.75 kW and under 50 kW, 120,000 yen per kW.
● New homes: For systems under 3.6 kW, 120,000 yen per kW (maximum 360,000 yen); for systems over 3.6 kW and under 50 kW, 100,000 yen per kW.
● Additional amounts for the installation of rooftop frames and waterproofing work are also available.
The target is for unused panels with an output of under 50 kW that have obtained JET certification, installed in residential homes in Tokyo, and used in living areas. The process involves making a prior application and then applying for the grant after installation. From the prior application for fiscal year 2026, it has become mandatory to submit a certificate issued by a financial institution at the time of performance reporting.
According to the official page of Tokyo, prior applications have been accepted since May 29, 2026. It will end once the budget is reached, so please check the official page for the reception status.
👉 Click here for the official page of Tokyo (Cool Network Tokyo)
Tokyo “Home 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)
●Battery unit expansion: 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 installation must be completed between April 1, 2026, and March 30, 2027. If applying in advance after October 1, 2026, only products registered in the national SII for the fiscal year 2026 will be eligible.
The official Tokyo page states that pre-applications have been accepted since May 29, 2026. For detailed information, including conditions for combining with solar power generation, please check the official page.
👉 Click here for the official Tokyo (Cool Net Tokyo) page
Ome City “Residential Energy-Saving Equipment Promotion Subsidy System” (Fiscal Year 2026)
This subsidy is for homeowners who are registered residents in the city and install high-insulation windows, solar power generation equipment, batteries, etc. It applies to installations made after April 1, 2025, and is a post-application system after installation.
●Solar power generation: 15,000 JPY per kW (up to 60,000 JPY for 1 kW or more)
●Batteries: 5,000 JPY per kWh (up to 30,000 JPY for those connected to solar power generation)
●High-insulation windows: 50,000 JPY or half of the personal burden amount, whichever is lower
As the budget limit for fiscal year 2026 has been reached, applications are now closed, as stated on the official page of Ome City (confirmed as of October 7, 2026). There are no plans for the next fiscal year listed on the official page, so those considering applying should check the latest information on the city’s Environmental Policy Division or the official page.
Conditions for eligible equipment and application methods may change.
👉 Click here for the official Ome City page
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 installed on a 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 approximate amounts and may vary based on wiring length, scaffolding area, existing roofing materials, panel layout, etc.)
▶ Installation Menu | Costs for Solar Panel Installation and Battery Installation
Items to Confirm in the Estimate (Cost Check)
When comparing estimates, it is common to compare different capacities and equipment. Please check if the following items are clearly stated in each company’s estimate!
| 1. Solar Panels | Manufacturer, model number, output per panel (W), number of panels, total installation capacity (kW) should be 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 (entire 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, presence of a monitor to check power generation. |
| 6. Roof Reinforcement and Waterproofing | Details of waterproofing treatment at 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 | Scope and quantity of scaffolding. If it is simultaneous with roof work or exterior painting, check that the same scope and quantity are not counted twice. |
| 9. Removal and Disposal | Whether the removal of existing solar 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, both the amount and power generation will change. Kakeru Koumuten Co., Ltd. welcome comparisons, so if you bring estimates from other companies, we will explain the differences for each item!
Self-Estimate and Profit Simulation 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 and 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 Installations
| 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 Manufacturing/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 subsidy being granted, the actual burden amount is approximately 1,000,000 JPY Estimated recovery period for construction costs: about 8-9 years (self-consumption) *The subsidy 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 installation of solar panels and storage batteries. I heard that subsidies are available, and I would like to know how much will be granted. |
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 subsidy, so we explained it to the customer along with the estimate!
How to Choose a Solar Panel Installation Contractor in Ome City, Tokyo
There are many solar panel installation contractors available in Ome City, Tokyo, and you may be unsure which contractor to choose.
Therefore, when requesting solar panel installation and battery storage installation work, let’s confirm the following four points.
● 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 (three companies is a guideline)
● Check if they provide support for subsidy applications
By confirming the above four points, you will be able to choose a reliable contractor.
Have knowledge not only about solar panels but also about roofs
Defective installation of solar panels can sometimes be caused by a lack of knowledge and confirmation 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
・Installing solar panels on a deteriorated roof, leading to leaks
・Installing solar panels on a roof with a short lifespan, necessitating removal and remodeling within a few years
・Misjudging the type of waterproofing and performing incorrect treatment, 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, confirm the presence of warranties. It is important to check not only the duration of the warranty but also the coverage, exclusions, and cost conditions.
Solar panels and battery storage units come with manufacturer warranties, but 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 cover the repairs under the warranty, provided it is within the warranty period and conditions.
Additionally, some contractors offer aftercare services separate from warranties, so be sure to check if the contractor you are considering has aftercare services.
Since abnormalities or damage on the roof may not be visible, you may not notice them yourself.
By conducting inspections of hidden areas during aftercare maintenance, you can more easily detect abnormalities early and prevent major repairs or failures!
Kakeru Koumuten Co., Ltd. offers a leak warranty as part of the workmanship warranty for solar panel installations. (The warranty for solar panel installations is 10 years, and depending on the condition of the roof before installation, a roof renovation may be required to provide the warranty.)
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 a solar panel installation, let’s obtain estimates from multiple contractors.
Even for the same manufacturer and the same construction details, costs may vary, and warranties and after-sales services may differ.
Additionally, obtaining multiple estimates makes it easier to negotiate prices.
To request your desired contractor at a lower price, we recommend obtaining estimates from multiple contractors.
When comparing estimates,
“Check the items in the estimate”
“Type of solar panel”
“Warranties and after-sales services”
let’s carefully compare and make a judgment! If the rank of auxiliary materials is low or if processes are skipped, costs can be reduced, so avoid judging solely based on price!
▶ Go 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 solar panel installations and battery installations, 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 that require prior application, such as the Tokyo Metropolitan Government’s subsidies, it is reassuring to have a contractor that supports the preparation of necessary documents and the flow of procedures.
Complete the procedures specified for each system (for Tokyo’s subsidies, prior application is required) before proceeding with the construction!
For Tokyo’s subsidies, after installation, a grant application and performance report will be submitted, and after review, the grant will be awarded! (The flow of procedures varies by system)
▶ Go to “Subsidies and grants that may be applicable in Ome 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 electricity generated, you can reduce the amount of electricity purchased from the utility company and gain benefits!
As electricity costs rise, the ability to cover your power 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 (less than 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 at home (self-consume) rather than sell it, making the combination with a storage battery a viable option.
👉 Ministry of Economy, 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!
Reducing the actual burden amount through subsidies is a significant advantage!
In the case of Ome City, there is a possibility of being eligible for the national, Tokyo, and Ome City programs. The subsidy application in Ome City is a post-application after installation, but it has been reported that the budget limit for the 2026 fiscal year has been reached and applications are closed (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, equipment such as power conditioners may have operational noise.)
Advantage 4 Heat insulation effects are expected!!
By installing them on the roof or rooftop, the panels block direct sunlight from hitting the roof.
Especially in summer, it can help reduce the temperature of the roof, providing expected heat insulation effects!
（This does not improve the insulation performance of the building 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 daytime generation.
（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 remodeling 10 to 20 years later, there will be costs for removing and reinstalling the solar panels.
If the existing roof is deteriorated, it is reassuring to remodel 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 ask for a simulation considering 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 differ by construction method, but in methods that fix brackets to the roofing material or substrate with screws, waterproofing of the fixed parts becomes crucial.
In methods that involve making holes in the roof, the risk of leaks inevitably arises.
Of course, we will perform thorough waterproofing, but if you are concerned about making holes, one option is to replace the roofing material with a metal roof and fix the solar panels using the catch method.（The catch method has compatibility conditions between the roofing material and brackets, and it cannot be used with all metal roofs）
Foundation Bracket for Horizontal Metal Roofs
Note 3: The Roof Becomes Heavier
As solar panels are installed, the roof will become heavier. After investigating the existing roof, substrate, and load-bearing capacity, switching to a lighter roof may be one 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!
Choosing Point 1: Compare Based on Total Output of the Roof
When installing solar panels on the roof, it is important to consider how much electricity can be generated in the limited area, and generating more electricity is always better!
Solar panels come in various sizes and outputs depending on the manufacturer.
A panel with an output of 350W and a panel with an output of 400W may seem that the higher output panel is better at first glance.
However, if the size of the panel does not fit well on the roof, “20 panels of 350W can be installed, while only 15 panels of 400W can be installed,” meaning the number of panels that can be installed may differ even on the same roof due to size differences.
400W×15 panels = 6kW (Total output of the roof)
350W×20 panels = 7kW (Total output of the roof)
As shown above, even if the output of one 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 is a calculation of total output (kW). The actual electricity generation (kWh) will vary depending on conditions such as roof orientation, slope, and shading.
Choosing Point 2: Compare Based on Degradation Rate of Solar Panels
Solar panels have a degradation rate, and their output gradually decreases over 10 or 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.
Choosing solar panels while considering the degradation rate, rather than just the initial output, will lead to a regret-free decision!
Choosing Point 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.
Regarding the output warranty, some manufacturers offer a 30-year warranty while others provide a 10-year warranty, so it varies widely!
It’s always better to have a longer warranty, so let’s check the warranty periods and conditions of the manufacturers you are considering!
Frequently Asked Questions about Solar Power and Storage Battery Installation in Ome City, Tokyo
We have compiled frequently asked questions from customers considering the installation of solar panels and storage batteries in Ome City, Tokyo. (Tap to open the answers)
How much does it cost to install solar panels and storage batteries in Ome 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.
For cost estimates by capacity, please refer to the solar panel installation and storage battery installation pricing page. We will create a layout diagram from the drawings and on-site survey and provide a free estimate!
Are there any subsidies available for solar power and storage battery installation in Ome City, Tokyo?
As of October 7, 2026, Tokyo’s “Solar Power Generation Promotion Project for Households” (for existing homes, 15,000 yen per kW for up to 450,000 yen) and “Storage Battery Promotion Project for Households” (100,000 yen per kWh for up to 1.2 million yen per household) are accepting pre-applications starting May 29, 2026, as posted on the official Tokyo (Cool Net Tokyo) page. Ome City has a residential energy-saving equipment promotion subsidy system (for solar power generation, 15,000 yen per kW with a maximum of 60,000 yen, and for storage batteries, 5,000 yen per kWh with a maximum of 30,000 yen), but it has been reported on the official page of Ome City that the application has ended for the fiscal year 2026 due to reaching the budget limit. The national DR home storage battery project has also closed its public recruitment.
Since the application status may change, please check the subsidy and grant section and consult with us before signing a contract.
Can I apply for subsidies after the construction is completed?
It depends on the system. Tokyo’s subsidies require pre-application, while Ome City’s grants allow for post-application after installation. Conditions such as whether you can contract and start construction before applying differ 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 a slate roof? I’m worried about leaks.
It is possible to install on a slate roof, but it is necessary to check the condition of the roofing material and substrate. The fixing method varies by construction method, and when fixing brackets 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 and suggest methods such as roof overlay (cover method) or complete replacement if deterioration is progressing.
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 after 10 to 20 years of installation, there will be additional costs for removing and reinstalling solar panels. If the remaining lifespan of the roof is short, it may be more cost-effective to renovate with durable roofing materials before installation.
Please consult us on how to proceed with the installation after confirming the condition of the roof through a 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 advantageous 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) is aimed at increasing the self-consumption of electricity generated by solar power. The subsidy program in Ome City also includes storage batteries that are linked with solar power generation (applications for Reiwa 8 have ended). You can compare “solar power only” and “solar power + storage battery” through a financial simulation.
How many kW can I install on my roof? Is it okay for north-facing roofs or roofs with shadows?
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 site survey, and provide you with the installation capacity and power generation simulation.
Ome City consists of mountainous and hilly areas, as well as a fan-shaped plateau in between, with river terraces along the Tama River. The shape and orientation of the roof, as well as the shading from surrounding buildings, will differ 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?
In the above construction case (solar panel 4.3 kW + 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.
Please note that there will be an additional period for applying for subsidies and to the power company, so please consult us early.
What is the current selling price (FIT) for electricity?
For residential use (under 10 kW), the selling price from 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 the 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 handle maintenance and inspections after installation?
Yes, we can. Kakeru Koumuten sends out annual after-maintenance notices via DM and visits customers who wish to have inspections. We can also clean 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, we can. 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 detachment and water heater removal pricing page.
If you are looking for a solar panel installation company in Ome City, Tokyo, please consult Kakeru Koumuten
Our company handles many exterior renovations, including solar panels, roof work, and exterior wall work in Ome City, Tokyo.
We have received requests from many customers, including renovation companies and real estate companies, who have contacted us!
Kakeru Koumuten Co., Ltd. promises “high-quality renovations at low cost”, and we have received great feedback from numerous 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 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 recommended solar panels”, “I want to keep costs down as much as possible”, “I just want an estimate for now”, we will provide optimal 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 lose in terms of cost, quality, and organization compared to other companies in exterior construction!
We welcome competitive estimates because we are confident!
Estimates are completely free, and if you find our company to be inferior to others, feel free to decline!
Characteristics of Ome City, Tokyo and Points of Solar Work
Ome City is located approximately 50 kilometers northwest of the city center, covering an area of 103.31 square kilometers. The central and western parts are mountainous, while the northeastern and southeastern parts are hilly, with a fan-shaped plateau in between, and there are river terraces along the Tama River. We have summarized the characteristics of the terrain in Ome City, Tokyo, and points to consider when installing solar panels and storage batteries below. (Tap to open)
View the characteristics of Ome City, Tokyo, and points for solar installation
■ Mountains, hills, plateaus, and river terraces. Check elevation differences and delivery routes for each area
Ome City has the Tama River flowing from west to east, continuing from the flatlands in the east to the hills and mountains, with the highest point in the city being Nabewari Mountain at 1,084 meters. Even within the same city, the width of the roads and the elevation differences of the properties vary between flat residential areas and those with many hills and slopes. 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 site surveys, and you can check the power generation simulation.
■ Check the hazard maps for floods, internal water, and landslides. Pay attention to the installation locations of equipment
Ome City’s disaster prevention map includes maps for Tama River flood hazards, internal water, landslides, Mount Fuji volcano, heavy snowfall, and more. Additionally, the landslide warning areas and special warning areas are designated by Tokyo Metropolitan Government and can be checked on the city’s Ome map information system and Tokyo’s maps. Depending on where the power conditioner and storage battery are installed, separate from the panels on the roof, the impact during disasters may vary. Please check the assumptions for your location on the city’s maps and consult about the installation location and height in accordance with the installation conditions of the manufacturer you will use.
■ 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, their ages, and the shapes of the properties 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 confirm the type and condition of the roof and the situation of the property before installation, and propose fixing methods, waterproofing details, and scaffolding plans.
■ The annual sunshine hours at the Tokyo Observatory are approximately 1,927 hours
According to the Japan Meteorological Agency’s average values (1991-2020), the annual sunshine hours at the Tokyo Observatory are approximately 1,927 hours, with January (about 193 hours) being the most and June during the rainy season (about 124 hours) being the least. (This is a reference value, not an observation value within Ome City)
The power generation amount in Ome City can also change due to surrounding buildings, trees, and mountains, so it is important to conduct an annual power generation simulation and choose the capacity of the storage battery according to the times when electricity is used the most.
Our company handles many exterior construction and solar installation projects in Ome 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 for any sudden troubles!
Service Area in Ome City, Tokyo
Kakeru Koumuten Co., Ltd. accepts requests throughout Kanagawa Prefecture and all of Tokyo.
List of Areas in Ome City, Tokyo
Ome City, Amagase Town / Ome City, Imai / Ome City, Imadera / Ome City, Urayado Town / Ome City, Oyanagi Town / Ome City, Kosogi / Ome City, Katsunuma / Ome City, Kabe Town / Ome City, Kamimachi / Ome City, Kinoshita / Ome City, Kurosawa / Ome City, Komaki Town / Ome City, Sawai / Ome City, Shiofune / Ome City, Shinmachi / Ome City, Suehiro Town / Ome City, Sume Town / Ome City, Daimon / Ome City, Takinoue Town / Ome City, Chigase Town / Ome City, Tomioka / Ome City, Tomoda Town / Ome City, Nakacho / Ome City, Nagabuchi / Ome City, Naruki / Ome City, Nishibun Town / Ome City, Negabu / Ome City, Nogami Town / Ome City, Umegou / Ome City, Hatanaka / Ome City, Higashi-Ome / Ome City, Hinatawada / Ome City, Fukiage / Ome City, Fujihashi / Ome City, Futamatao / Ome City, Honmachi / Ome City, Mitake / Ome City, Mitake Mountain / Ome City, Mitake Honmachi / Ome City, Morishita Town / Ome City, Morioka Town / Ome City, Taniyano / Ome City, Yuzuki Town / Ome City, Wada Town
・For exterior wall painting in Ome City, Tokyo, trust Kakeru Koumuten Co., Ltd.!
・For roof renovations in Ome City, Tokyo, trust Kakeru Koumuten Co., Ltd.!
・For exterior renovations in Ome City, Tokyo, trust Kakeru Koumuten Co., Ltd.!
・Kakeru Koumuten Co., Ltd. project achievements
・Kakeru Koumuten Co., Ltd. aftercare services
・Kakeru Koumuten Co., Ltd. service menu and price list
・Kakeru Koumuten Co., Ltd. staff blog and announcements
・Explaining the importance of comparative estimates and key points!
・Top 12 solar power manufacturers! Features and selection tips included!
・What are the installation costs for solar power? Comprehensive tips to reduce costs!
・What are the best locations for solar power installation? Key points for site selection included!
・Check out our solar power estimates here!
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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!
