For
Solar Panel and Storage Battery Installation in Meguro, Tokyo
Kakeru Koumuten is at your service!

Kakeru Koumuten is a specialized exterior renovation company based in Aoba Ward, Yokohama City.
As a company strong in roofing work, we are entrusted withsolar panel installation and storage battery installation considering roofing and waterproofing!

“How to Choose a Solar Panel Contractor in Meguro”
“Costs for Solar Panel and Storage Battery Installation”
“Subsidies Available for Solar System Installation in Meguro”
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 obtainingthree estimates!

Solar Panel and Storage Battery Installation in Meguro, Tokyo by Kakeru Koumuten
Table of Contents (Tap to Expand)
  1. Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Meguro, Tokyo
  2. Roof Inspection Before Installing Solar Panels
  3. Subsidies and Grants Available in Meguro
  4. Price List for Solar Panel and Storage Battery Installation
  5. Breakdown of Installation Capacity, Equipment, and Construction Costs
  6. Self-Estimate and Profit Simulation for Solar Power Generation
  7. Customer Testimonials
  8. Case Studies of Solar Panel Installations
  9. How to Choose a Solar Panel Installation Company in Meguro, Tokyo
  10. Benefits of Introducing Solar Equipment
  11. Points to Consider When Introducing Solar Power Generation
  12. How to Choose Solar Panels
  13. Frequently Asked Questions About Solar and Storage Battery Installation in Meguro
  14. If You Are Looking for a Solar Panel Installation Company in Meguro, Contact Kakeru Koumuten
  15. Characteristics of Meguro, Tokyo and Points for Solar Work
  16. Service Area in Meguro, Tokyo

Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Meguro, Tokyo

Link Banner to Kakeru Koumuten's Strengths Page

The reasons why our company is entrusted with solar panel installation by customers in Meguro, Tokyo include
one reason being that “Kakeru Koumuten covers Kanagawa and Tokyo as its service areas”,
and we have “strengths in solar panel installation that cannot be imitated by other companies”, which has received high praise from many customers.

In solar panel installation work in Meguro, we have absolute confidence in “cost,” “quality,” and “plans”,
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!

Installation work of solar panels on the roofSolar panels installed on the roof
Troubles such as leaks that occur during solar panel installation may be caused by 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 knowledge 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 work and exterior renovations.
We have established five bases centered around Yokohama City, Kanagawa Prefecture for material storage and showrooms.

In-house Ownership of Scaffolding Materials

Entrance to the material storage areaCompany-owned 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 in the residential area of Meguro Ward, our own scaffolding team will plan the scaffolding according to the site conditions.

Storage of materials in our large warehouse

Exterior of the material warehouse Interior of the warehouse storing materials
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 cost!
Additionally, we always have stock of roofing materials, so we canrespond quickly in emergencies!

Sorting and transporting waste materials in-house

Sorting space for waste materialsThe 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.

Showroom dedicated to exterior renovations

Exterior renovation dedicated showroom appearanceShowroom interior
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 explain the structure, allowing for detailed explanations!

3.All Work Performed by Our Own Team

Diagram of our system for scaffolding, painting, and roof renovation 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 person in charge does not change, whether it is the sales representative or the construction management representative, smooth communication is possible.

We can perform everything from temporary scaffolding installation, exterior wall painting, to roof renovation with our own team!

4. Various Permits and Skilled Workers

Construction business licenseDisplay of permits and qualifications obtained by Kakeru Koumuten
We have obtained construction business licenses and industrial waste collection and transportation permits!
We also have nationally certified sheet metal and painting technicians, and we are confident in our construction skills.
We can also handle large-scale roofing projects such as factories!

5. Warranty and Aftercare

Link banner to Kakeru Koumuten's warranty information page

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 remodeling is performed. The workmanship warranty is separate from the manufacturer’s product warranty, and the coverage 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!

Maintenance of Solar Power Generation|Thorough Explanation of Importance, Frequency, and Cost Estimates!When introducing solar power generation, it is essential to consider...

6. Flexible and Prompt Response

Inspection response for roofs and solar panels

Our company is equipped to handle various roof troubles and situations.

If it is not possible to access the roof at high altitudes, we can utilize a drone for inspection!
During leakage investigations, we can also conduct surveys using a thermal imaging camera.

If the power generation of the solar panels decreases due to dirt, we can also provide cleaning with a specialized brush.
We will respond according to the customer’s wishes.

7. Human Resource Development

Training session using models

To improve skills, we create various roof models and conduct practical training.
Since the construction method changes depending on the shape and slope of the roof, we regularly provide technical training so that each staff member can respond to various cases.

Company Overview神奈川で家の外装・屋根の工事、修理なら一番若くて親切な株式会社翔工務店にお任せください。 株式会社翔工務店はリフォームを通して美しく理想の生活空間を創るお手伝いをしています。外装改修、外壁塗装、雨樋修理清掃、屋根の塗装や重ね葺き葺き変えなどの部分的な修理まで、お客様のどのようなご要望にも全力でお応えします。...

8. Creation of Easy-to-Understand Materials and Simulations

Materials and simulation examples provided for solar panel installation

At Kakeru Koumuten Co., Ltd., in addition to “estimates”, “layout diagrams”, and “power generation simulations”, we also provide a “solar installation guidebook” and a “financial simulation” that takes into account loan interest rates and electricity costs.
The financial simulation can be created for projected cumulative income and expenses over 20 to 30 years.
Even customers who are not familiar with solar installations will find the 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 safe to place them directly on the current roof, as this is the key point to prevent leaks and unnecessary expenses!
Kakeru Koumuten Co., Ltd., which specializes in roofing work, has summarized the items to check before installation.

1. Type of roofing material and age The method of securing the panels 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 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 power generation. We will create a layout diagram from 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 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 their size, so we will compare based on the total output of the roof.
5. Method of securing and waterproofing details We will confirm whether the panels will be secured by drilling holes in the roofing material or by using brackets to hold the roofing material. The method of securing varies by technique, so please check the waterproofing treatment of the fastening 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 also be an option if necessary.
7. Location of equipment installation and wiring We will check the installation location of 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.

Securing 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) Waterproofing of fixed 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 frame Type and deterioration status of the waterproof layer, waterproofing around the frame. Consider in conjunction with the timing of waterproofing work.
If you carry out roof renovations at the same time, you may be able to reduce future costs for removing and reinstalling solar panels!
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 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 in-house, so please consult us according to the condition of your roof!

▶ Click here for roof renovations in Meguro, Tokyo

Subsidies and Grants That May Be Applicable inMeguro, Tokyo

When introducing solar panels or storage batteries in Meguro, Tokyo, there may be applicable systems from “the national government,” “Tokyo,” and “Meguro City.”
The following information is based on the official pages of each system as of October 7, 2026. The application status may change due to budget and recruitment periods, 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 “Reiwa 8 Year Household Solar Power Introduction Promotion Project” (Cool Net Tokyo) New installation of certified solar modules in residential properties or their premises within Tokyo, with a system capacity of less than 50kW. Pre-application before installation is required. Existing homes: 150,000 JPY/kW for systems up to 3.75kW (maximum 450,000 JPY), 120,000 JPY/kW for systems over 3.75kW
New homes: 120,000 JPY/kW for systems up to 3.6kW (maximum 360,000 JPY), 100,000 JPY/kW for systems over 3.6kW
(Additional costs for mounting frames, waterproofing work, and renovation defect insurance may apply)
Pre-application: From May 29, 2026
Grant application and performance report: From June 30, 2026 to March 30, 2029
Tokyo “Reiwa 8 Year Household Storage Battery Introduction Promotion Project” (Cool Net Tokyo) New installation of storage batteries in residential properties, with the requirement that they are SII registered devices. This project is intended for simultaneous installation with solar power, but applications can be made for storage batteries alone. Pre-applications after October 1, 2026 will only be eligible for SII registered products for Reiwa 8. Storage battery package: 100,000 JPY/kWh (maximum 1,200,000 JPY per household)
Expansion of storage battery units: 60,000 JPY/kWh (maximum 720,000 JPY per household)
(Additional incentives for participation in DR demonstrations may apply)
Pre-application: From May 29, 2026
Grant application and performance report: From June 30, 2026
Meguro Ward “Subsidy for Installation Costs of Residential Renewable Energy and Energy-Saving Equipment” Reiwa 8 Year Individuals or managers defined by the Building Unit Ownership Act are eligible. The installation must be completed between January 1 and December 31, 2026, and pre-application is not required (contracts can be made before application). All necessary documents must be submitted at the time of application. Solar power generation system: 30,000 JPY per kW (maximum 150,000 JPY)
Home storage system: Within one-third of the equipment’s main price (maximum 70,000 JPY)
Application period: From June 1, 2026 to January 29, 2027 (first-come, first-served)
As of September 29, 2026, the application amount against the budget is reported to be 82.2% on the ward’s official page. The program may end once the budget is reached.
National “DR Household Storage Battery Project” (Reiwa 7 Year Supplement) New installation of 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 (applications are currently not accepted).
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 renovation of windows (openings) and the building structure; applications cannot be made for the installation of storage batteries alone. Solar panels are not included as eligible facilities. Storage Battery: 96,000 JPY/unit Ends as soon as the budget limit is reached. Please check the official website for the current status.
Please pay attention to the “order of procedures” for subsidies!
In Tokyo, a pre-application before installation is required for subsidies, and starting construction beforehand may exclude you from eligibility. In Meguro City, pre-application is not necessary, and contracts can be made before application, but you must meet requirements such as the timing of installation handover and necessary documents, and it is not guaranteed that you will receive the subsidy upon application. The Meguro City subsidy is on a first-come, first-served basis, and applications will close once the budget is reached. For combined use with national and Tokyo subsidies, please check the official pages of each system. Procedures differ by system, so please confirm before contracting or starting construction.
At Kakeru Koumuten, we will guide you on the eligibility conditions for each system after confirming them.

Tokyo “Reiwa 8 Year Household Solar Power Introduction Promotion Project”

In Tokyo, subsidies are provided for those installing solar power systems in residential homes through Cool Net Tokyo. The target is systems using certified solar cell modules installed newly in residential homes or on their premises, with a capacity of less than 50kW. A pre-application before installation is required.

For existing homes, the subsidy amount is 150,000 JPY/kW for 3.75kW or less (maximum 450,000 JPY), and 120,000 JPY/kW for over 3.75kW. Additionally, there are extra items such as installation of mounting frames, waterproofing work, and renovation defect insurance. The pre-application period is from May 29, 2026, and the application for grants and performance reports is from June 30, 2026, to March 30, 2029. For details on eligible equipment and conditions, as well as budget status, please check the official page.
👉 Cool Net Tokyo | Official page for solar power is here

Tokyo “Reiwa 8 Year Household Storage Battery Introduction Promotion Project”

Tokyo is also providing subsidies for newly installed storage batteries in residential homes. The subsidy amount is 100,000 JPY per kWh for storage battery packages (maximum 1,200,000 JPY/unit), and 60,000 JPY per kWh for additional storage battery units (maximum 720,000 JPY/unit), with additional amounts for participation in DR demonstrations.

The target is equipment registered with SII (Environmental Collaboration Initiative). If you apply for pre-application after October 1, 2026, only equipment listed in the Reiwa 8 year SII registered product list will be eligible. This project is intended for simultaneous installation with solar power, but applications can be made for storage batteries alone. The application for grants and performance reports has been open since June 30, 2026.
👉 Cool Net Tokyo | Official page for storage batteries is here

Meguro City “Subsidy for Installation Costs of Renewable Energy and Energy-Saving Equipment for Residential Use”

Meguro City provides subsidies for those installing renewable energy and energy-saving equipment in residential homes. The subsidy amount for Reiwa 8 year is 30,000 JPY per kW for solar power systems (maximum 150,000 JPY), and up to 70,000 JPY for home storage systems, which is within one-third of the equipment’s main price. The targets are individuals or managers of buildings as defined by the Building Unit Ownership Act.

No prior application required, and contracts can be made before application, but installation delivery must be between January 1, 2026, and December 31, 2026. Applications can be submitted online or by mail from June 1, 2026, to January 29, 2027, on a first-come, first-served basis. All necessary documents must be submitted at the time of application. According to the district’s official page, as of September 29, 2026, the percentage of application amounts against the budget is 82.2%.
👉 Here is the official page of Meguro City (Subsidy for installation costs of renewable energy and energy-saving equipment for residential use)

National Subsidy “DR Home Storage Battery Project (Support Project for Home Storage Systems for DR Resource Introduction)”

The 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). In the fiscal year 2025 supplementary budget, the subsidy amount is 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 items contracted or ordered before the grant decision are not eligible.

However, the supplementary budget for fiscal year 2025 reached the application amount on May 29, 2026, and the public recruitment has ended (the previous fiscal year’s supplementary budget also ended public recruitment on July 2, 2025). Applications are currently not possible, so please check the official site for future public recruitment.

Additionally, there are currently no subsidies confirmed for the installation of solar panels for existing homes.
👉 Here is the official site for the DR Home Storage Battery Project

Solar Panel Installation & Storage Battery Installation Price List

Construction menu for solar panel installation and storage battery installation
⇧ Construction Menu | For costs regarding solar panel installation and storage battery installation, click here

Solar Panel Removal and Hot Water Heater Dismantling Service Menu
⇧Service Menu | Click here for costs related to Solar Panel Removal and Hot Water Heater Dismantling

Estimate Guidance

Breakdown of Installation Capacity, Equipment, and Construction Costs

The costs for solar panels and storage batteries should be confirmed by separating them into “Equipment Costs (Device Costs)” and “Construction Costs”.
Even for the same “Solar Panel Installation Set,” the amount can vary significantly depending on the installation capacity, equipment grade, and roof condition.

Considerations for Installation Capacity (kW) and Storage 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 (kilowatts). Storage batteries are compared based on the amount of electricity they can store, expressed in kWh (kilowatt-hours).
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 panel costs as approximately 800,000 JPY to 1,200,000 JPY for 3-5 kW, and 1,200,000 JPY to 1,900,000 JPY for 6-10 kW. (These are just rough estimates and may vary based on wiring length, scaffolding range, existing roofing materials, panel layout, etc.)
▶ Service Menu | Click here for costs related to Solar Panel Installation and Storage Battery Installation

Items to Confirm in the Estimate (Cost Verification)

When comparing estimates, it’s common to compare different capacities and equipment by only looking at the amounts. Please check whether 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) are specified.
2. Power Conditioner Manufacturer, model number, capacity, number of units, installation location (indoor/outdoor). Check if it is a type that controls the battery together.
3. Storage Battery Manufacturer, model number, capacity (kWh), range usable during a power outage (entire house or specific circuits), installation location.
4. Mounting Frame and Fittings Name of fittings suitable for roofing materials and method of fixation (whether it is a method that drills holes or a method that clamps and secures).
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 fixation points, whether necessary roof repairs and substrate reinforcements are included.
7. Application Extent of support for applications to the power company, certification application for selling electricity (FIT), and subsidy applications.
8. Scaffolding Scope and quantity of scaffolding. If roof work and exterior painting are done simultaneously, confirm that the same scope and quantity are not counted twice.
9. Removal and Disposal Whether the removal of existing solar thermal water heaters and old panels, as well as disposal costs for waste materials, are included.
10. Tax Classification and Warranty Whether prices are tax-inclusive or tax-exclusive, conditions under which additional costs may arise, details and duration of manufacturer warranty and workmanship warranty.
Tips for Comparison: “Installation Capacity (kW)” and “Equipment Model Number” should be aligned for comparison!
If the capacities differ, the price and power generation will also change. Kakeru Koumuten Co., Ltd. warmly welcomes competitive estimates, 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

Self-Estimate and Profit Simulation for Solar Power Generation

With the simulator above,
you can obtain an approximate estimate and a profit 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 get an approximate estimate and profit simulation!
*The simulation results are approximate. Actual profits may vary based on assumptions such as electricity rates, self-consumption ratios, selling prices, and costs for equipment inspection and replacement.

Customer Feedback

Examples of Solar Panel Installation

BEFORE

Metal roof before solar panel installation

AFTER

Roof after solar panel installation

Work 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 Details
 Fixed by gripping the horizontal metal roof with catch type hardware (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
 Approximately 3 days
Completion Month
 April 2025
Inquiry Details
I am considering the installation 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 Meguro, Tokyo

There are many solar panel installation contractors that serve Meguro Ward, 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 4 points.

● Have extensive knowledge not only about solar power but also about roofs

● Confirm the presence of warranties and aftercare maintenance

● 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.

Which Solar Power Installation Company is Best? Introducing How to Choose Without Regret!When considering the introduction of solar power generation, the mos...

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 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 verification of roofs and waterproofing

・Installed solar panels on a severely deteriorated roof, resulting in leaks
・Installed solar panels on a roof with a short lifespan, necessitating a renovation to detach and reattach the solar panels within a few years
・Misjudged the type of waterproofing, leading to incorrect treatment and subsequent leaks
and more

When installing solar panels, understanding the condition and type of the existing roof allows you to avoid unnecessary expenses and unexpected troubles.

▶ Go to “Roof Verification Before Installing Solar Panels” in this article

Confirm the presence of warranties and aftercare maintenance

When choosing a solar installation contractor, let’s 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 a workmanship warranty in case leaks occur after installation!

For contractors that offer a workmanship warranty, if leaks occur after installation, they may be able to address the issue under the warranty, provided it falls within the warranty period and conditions.

Additionally, some contractors offer after-sales service separate from warranties, so be sure to check if the contractor you are considering has after-sales service.
Changes or damage on the roof can occur in areas that are not visible, so you may not notice them yourself.
By conducting inspections during after-sales maintenance, you can easily detect abnormalities early and prevent major repairs or breakdowns!

Kakeru Koumuten Co., Ltd. provides a leak warranty as part of the workmanship warranty for solar panel installations. (The warranty for solar panel installation 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 conduct after-sales maintenance and send out annual DM!
Please check the DM, and if you wish, we will visit for after-sales maintenance!

About Kakeru Koumuten Co., Ltd. WarrantyKakeru Koumuten Co., Ltd. provides a simple explanation of our roof construction, exterior wall painting, and sealing work guarantees!! We do not require any advance or interim payments!!...

Obtain estimates from multiple contractors (3 companies as a guideline)

When requesting solar panel installation, be sure to obtain estimates from multiple contractors.

Even for the same manufacturer and the same work content, costs may vary, and warranties and after-sales services may differ.

Additionally, obtaining multiple estimates makes price negotiations easier.

To request from your preferred contractor at a lower price, we recommend obtaining estimates from multiple contractors.

When comparing estimates, please check the following:

“Check the items in the estimate”
“Type of solar panel”
“Warranties and after-sales services”

Make detailed comparisons to make your decision! If the rank of auxiliary materials is low or if processes are skipped, costs can be reduced, so avoid making decisions based solely on cost!

▶ Go to “Breakdown of Installation Capacity, Equipment, and Construction Costs” in this article

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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 subsidy may not be granted.
There are systems that require personal applications and cannot be handled by the contractor, as well as systems that require prior application before installation, so 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 before installation) before proceeding with the construction! In Meguro Ward, prior application is not required, and contracts can be made even before application!

In the case of subsidies in Tokyo, the process involves submitting a grant application and performance report after the completion of the work, which will then be reviewed before the grant is awarded! For the subsidy in Meguro Ward, you will need to gather the necessary documents and apply after the installation handover, which will also be reviewed before the grant is awarded! (The procedure may vary depending on the system.)

▶ Go to “Subsidies and Grants that May Be Applicable in Meguro Ward” within this article

Benefits of Introducing Solar Power Equipment

The benefits of introducing solar panels are summarized in the following five points!

Benefit 1: Economic Advantage

Illustration of household budget

The biggest advantage of introducing solar panels is the economic benefit!
While the selling price of electricity has decreased compared to ten years ago, you can gain benefits by reducing the amount of electricity purchased from the utility company by consuming the electricity generated!
As electricity prices rise, the ability to cover your consumption with solar power becomes increasingly 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 generally more advantageous to use the electricity at home (self-consumption), making the combination with a storage battery a viable option.
👉 For purchase prices and periods, visit the Agency for Natural Resources and Energy

Benefit 2: You Can Utilize Subsidies!

Illustration of a person happy about reduced costs

The conditions and amounts of subsidies vary by prefecture and municipality, but if you meet the requirements, you may be able to utilize subsidies!
The reduction of the actual burden amount through subsidies is a significant advantage!
In the case of Meguro Ward, in addition to national and Tokyo metropolitan programs, there may be eligibility for the Meguro Ward Residential Renewable Energy and Energy Conservation Equipment Installation Subsidy (30,000 yen per kW for solar power generation, with a maximum of 150,000 yen; for storage systems, within one-third of the main price, with a maximum of 70,000 yen) (no prior application is required for the ward’s subsidy, and it is on a first-come, first-served basis).

Benefit 3 Environmentally Friendly!

Illustration of environmentally friendly solar power generation

Solar power generation contributes to the mitigation of global warming by reducing carbon dioxide emissions and dependence on fossil fuels.
Since solar panels do not produce noise or exhaust gases during the power generation process, they are considered an environmentally friendly method of generating electricity. (Devices like power conditioners may produce operational noise)

Benefit 4 Expect heat insulation effects!!

Illustration of heat insulation by solar panels

By installing them on the roof or rooftop, the panels block direct sunlight from hitting the roof.
Especially in summer, they can help reduce the temperature rise of the roof, 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!!

Illustration of a house that can use electricity during a power outage

If a storage battery is installed, it is possible to use electricity even during emergencies like 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)

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What points should be noted when introducing solar power generation?

Next, we will explain the “three points to note” when installing solar panels!

Illustration of a person explaining points to note

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 reinstalling the solar panels.
If the existing roof is deteriorating, it is reassuring to renovate it with durable roofing materials before installing 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 consider maintenance costs in simulations before introducing solar panels!

Point 2 The risk of leaks increases depending on the roofing material

The methods for securing slate roofs and tile roofs vary depending on the construction method, but when using screws or other fasteners to secure the roofing materials and substrate, waterproofing at the fastening points becomes crucial.
In methods that involve making holes in the roof, there is inevitably a risk of leaks.
Of course, we will ensure proper waterproofing, but if you are concerned about making holes, replacing the roofing material with a metal roof and securing solar panels using the catch method is also an option. (The catch method has compatibility conditions between the roofing material and the fasteners, and it cannot be used with all metal roofs.)

Catch-type base fasteners for horizontal metal roofsCatch-type base fasteners for horizontal metal roofs

Note 3: The roof will become heavier

As solar panels are added, the roof will become heavier. After investigating the existing roof, substrate, and load-bearing capacity, replacing it with a lighter roof may also be an option if necessary.

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How to Choose Solar Panels?

There are many manufacturers of solar panels, and their output and costs vary widely.
It is not accurate to say that “this manufacturer has the best solar panels”; instead, 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 Method 1: Compare by Total Output of the Roof

When installing solar panels on the roof, it is important to know how much electricity can be generated in a limited area, and the more electricity generated, the better!

Solar panels come in various sizes and outputs depending on the manufacturer.
A panel with 350W output and a panel with 400W output may seem that the one with higher output is better at first glance.
However, if the size of the panel does not fit well with 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 installation capacities on the same roof due to the size difference.

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 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.

Choosing Method 2: Compare by Degradation Rate of Solar Panels

Solar panels have a degradation rate, and their output gradually decreases over 10 and 20 years.
The degree of output reduction after long-term use varies by product. The manufacturer’s output guarantee values are standard figures for warranty purposes and do not indicate the actual degradation rate or power generation amount.
Choosing solar panels while considering both initial output and degradation rates will lead to a decision without regrets!

How to Choose 3: Compare by Warranty Years

There are several types of warranties for solar panels, including “output warranty,” “natural disaster warranty,” and “system warranty,” and the warranty periods differ by manufacturer.
Some manufacturers offer a 30-year output warranty, while others provide a 10-year warranty, so it varies widely!
A longer warranty is always better, so be sure to check the warranty period and conditions of the manufacturers you are considering!

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Frequently Asked Questions about Solar Power and Storage Battery Installation in Meguro Ward

We have compiled frequently asked questions from customers considering the installation of solar panels and storage batteries in Meguro Ward. (Tap to open the answers)

How much does it cost to install solar panels and storage batteries in Meguro Ward, 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 power and storage battery installation in Meguro Ward?

As of October 7, 2026, Tokyo’s subsidies for solar power generation and storage batteries (Cool Net Tokyo) are accepting pre-applications. For storage batteries, only SII registered devices (registered products for Reiwa 8) will be eligible from pre-applications made after October 1, 2026. The subsidy for residential renewable energy and energy-saving equipment installation in Meguro Ward (30,000 yen per kW for solar power generation, with a maximum of 150,000 yen; for storage systems, within one-third of the main price, with a maximum of 70,000 yen) is open until January 29, 2027, and the official page of the ward states that as of September 29, 2026, the application amount ratio against the budget is 82.2% (first-come, first-served basis, ending when the budget is reached). The national DR household storage battery project has already closed its public recruitment.

Since the acceptance status may change, please refer to the subsidy and grant section and consult with us before signing a contract.

Can I apply for subsidies after the construction is completed?

For many programs, procedures must be completed before construction. Tokyo’s subsidies require pre-application before installation, and if you install first, you will be ineligible. On the other hand, Meguro Ward’s grants do not require pre-application, and contracts can be made before application. Procedures differ by program.

Since the order of procedures varies by program, please confirm before signing a contract or starting construction.

Can solar panels be installed on slate roofs? 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 beforehand. The fixing method varies depending on the construction method, and when fixing brackets to the roofing material or substrate, waterproof treatment of the fixed parts is essential.

Kakeru Koumuten Co., Ltd. is a company specializing in exterior renovations with strong expertise in roofing work, so we will check the condition of the roof before installation and suggest methods such as roof overlay (cover method) or replacement if deterioration is advanced.

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 10 to 20 years after installation, the cost of removing and reinstalling solar panels will be incurred separately. If the remaining lifespan of the roof is short, it may be more cost-effective to renovate to a highly durable roofing material before installation.

Please consult us on how to proceed with the installation 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 of 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 Tokyo Metropolitan Government’s subsidy for storage batteries is designed for simultaneous installation with solar panels, but applications can also be made for storage batteries alone. You can compare “solar panels only” and “solar panels + storage battery” in a financial simulation.

How many kW can be installed 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 Co., Ltd., we create a layout diagram from the drawings and on-site survey, and provide the installation capacity and power generation simulation.

Even in residential areas of Meguro Ward, the shadow cast by surrounding buildings varies from house to house. You can check the expected power generation through the power generation simulation.

How long will the construction period be?

In the above construction example (solar panel 4.3 kW + storage battery), it took about 3 days. The duration may vary depending on whether roofing work is done simultaneously and the shape and installation capacity of the roof.

Please note that there will be an additional period for applications for subsidies and power companies, so please consult us as soon as possible.

What is the current selling price (FIT)?

For residential use (under 10 kW), from the certification after October 2025, the first 4 years will be 24 yen/kWh, and from the 5th to the 10th year it will be 8.3 yen/kWh, with the same price applied in the 2026 fiscal year.

The idea is to recover initial costs more quickly in the first four years and then focus on self-consumption. Kakeru Koumuten Co., Ltd. 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 Co., Ltd. sends out annual after-service maintenance DM notices and visits for inspections upon request from customers. We can also clean solar panels using a special brush if the power generation is reduced due to dirt.

The roof is a place that is difficult to check by yourself, so please feel free to consult us if you have any concerns.

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, all in one consistent process. 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.

Get a free estimate for solar panels and storage batteries in Meguro City here

Estimates are completely free. We welcome competitive estimates!

If you are looking for a solar panel installation contractor in Meguro City, please consult Kakeru Koumuten

Our company handles many exterior renovations, including solar panels, roof work, and exterior wall work in Meguro City, Tokyo.
We receive requests from many customers, including renovation companies and real estate agencies, who contact us!

Kakeru Koumuten promises “high-quality renovations at low cost”, and we have received great feedback from many customers.
We continue to update our annual construction achievements and will strive to improve quality to satisfy even more customers in the future.

Our company can perform not only roof overlay work and re-roofing but also partial roof repairs, exterior painting, and exterior wall cover methods, all with our own team.
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 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 are confident, so we welcome competitive estimates!
Estimates are completely free, and if our company is found to be inferior to others, you are free to decline!

Characteristics of Meguro City, Tokyo and Points for Solar Work

Meguro Ward, located in the southwestern part of Tokyo’s 23 wards, is adjacent to Shibuya Ward, Shinagawa Ward, Setagaya Ward, and Ota Ward. The official page of Meguro Ward provides a flood hazard map (indicating flooded areas and their extent) and a landslide hazard map, with designated landslide warning areas within the ward.
We have summarized points to consider when installing solar panels and storage batteries in the residential environment of Meguro Ward below. (Tap to open)

View the characteristics of Meguro Ward, Tokyo, and points for solar construction

■ Check the installation locations for storage batteries and power conditioners against the hazard map

The flood hazard map of Meguro Ward shows the areas that could potentially be flooded and the extent of flooding for the maximum expected scale of flooding. Additionally, the landslide hazard map includes designated landslide warning areas within the ward (in April 2025, Tokyo designated new warning areas, and the map was updated in October of the same year). When deciding on the installation locations for storage batteries and power conditioners, it is advisable to check the flood assumptions and designated warning areas for your residence on the hazard map to consider the height and position of the installation for peace of mind.

■ Tokyo’s annual sunshine hours are approximately 1,927 hours

The Japan Meteorological Agency’s average values (1991-2020) indicate that Tokyo has approximately 1,927 hours of sunshine annually.
Since power generation varies by season, it is important to conduct annual power generation simulations and choose the capacity of the storage battery according to the times when electricity is used the most.

■ Check for shadows from surrounding buildings in closely built areas

In areas where houses are closely built, the shadows cast by surrounding buildings vary for each house depending on the roof’s orientation and height. Since solar panels generate less power when shaded, Kakeru Koumuten creates layout diagrams based on the drawings and the actual site conditions, allowing you to confirm through power generation simulations.

■ No prior application is required for the ward’s subsidies, but pay attention to the timing of installation handover and documents

In Meguro Ward, subsidies can be applied for before the contract is made, and prior application is not necessary; however, the installation handover must occur between January 1 and December 31, 2026. It is essential to submit all necessary documents at the time of application, so it is important to prepare the documents in conjunction with the construction schedule.

■ In places with narrow front roads, plan scaffolding and equipment delivery carefully

In areas with narrow front roads or where surrounding buildings are close together, careful planning for scaffolding and equipment delivery may be necessary. Kakeru Koumuten will respond to the site conditions with our own scaffolding team and scaffolding materials.

■ Check the roof condition according to the age of the building

For buildings that have been around for several years, it is important to check the condition of the roofing materials and substrate before installing solar panels. Depending on the condition of the roof, installing them simultaneously with roof renovations can help reduce future costs for removing and reinstalling solar panels.

■ Subsidies require prior application in Tokyo, but not in Meguro Ward

In Tokyo, prior application to Cool Net Tokyo is required before installation. In Meguro City, the Subsidy for Residential Renewable Energy and Energy-Saving Equipment Installation does not require prior application and will close once the budget is reached on a first-come, first-served basis. It is important to check the procedures and periods for each system in advance, in conjunction with the timing of the construction.

Our company serves Kanagawa Prefecture and Tokyo, and we handle many exterior and solar construction projects in Meguro 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 Meguro City, Tokyo

Kakeru Koumuten accepts requests throughout Kanagawa Prefecture and all of Tokyo.

List of Areas in Meguro City, Tokyo

Aobadai, Meguro City / Ookayama, Meguro City / Ohashi, Meguro City / Kakinokizaka, Meguro City / Kamimeguro, Meguro City / Komaba, Meguro City / Gohongi, Meguro City / Shimomeguro, Meguro City / Jiyugaoka, Meguro City / Senzoku, Meguro City / Hira-machi, Meguro City / Takaban, Meguro City / Chuo-machi, Meguro City / Nakacho, Meguro City / Nakane, Meguro City / Nakameguro, Meguro City / Haramachi, Meguro City / Higashigaoka, Meguro City / Higashiyama, Meguro City / Himonya, Meguro City / Mita, Meguro City / Midorigaoka, Meguro City / Minami, Meguro City / Meguro Honcho, Meguro City / Meguro, Meguro City / Yakumo, Meguro City / Yutenji, Meguro City

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For roof, gutter and exterior construction and repairs in Kanagawa,
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!