Leave the installation of solar panels in Zama City, Kanagawa Prefecture to Kakeru Koumuten Co., Ltd.!
For
Solar Panel and Storage Battery Installation in Zama City, Kanagawa Prefecture,
trust Kakeru Koumuten Co., Ltd.!
Kakeru Koumuten Co., Ltd. is a specialized exterior renovation company headquartered in Aoba Ward, Yokohama City.
As a company strong in roofing work, we are entrusted withsolar panel and storage battery installation considering roofs and waterproofing!
“How to Choose a Solar Panel Contractor in Zama City”
“Costs for Solar Panel and Storage Battery Installation”
“Subsidies Available for Solar System Installation in Zama City”
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 or so estimates!
Table of Contents (Tap to Expand)
- Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Zama City, Kanagawa Prefecture
- Roof Inspection Before Installing Solar Panels
- Subsidies and Grants That May Apply in Zama City
- 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 Installer in Zama City, Kanagawa Prefecture
- 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 Zama City
- If You Are Looking for a Solar Panel Installer in Zama City, Contact Kakeru Koumuten
- Characteristics of Zama City, Kanagawa Prefecture and Points for Solar Construction
- Service Area in Zama City, Kanagawa Prefecture
Reasons Why Kakeru Koumuten is Chosen for Solar Panel Installation in Zama City, Kanagawa Prefecture
The reasons why our company is entrusted with solar panel installation by customers in Zama City, Kanagawa Prefecture include
one reason being that Kakeru Koumuten has a base in Kanagawa Prefecture,
and our 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 multiple estimates!
1. We Can Also Handle Exterior Renovations Other Than Solar Panel Installation!
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 you are knowledgeable about solar panels, there are cases where the roof and waterproofing at the installation site are outside of your expertise, so caution is necessary.
It is reassuring to be knowledgeable about roofs 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
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 Zama City, where residential areas of hilly land, plateaus, and lowlands are mixed, our own scaffolding team will plan the scaffolding according to the site.
Storage of materials in our large warehouse
We store roofing materials and paints, and we can also store removed solar panels.
By ordering a large quantity of materials at once, we canpurchase materials at a lower cost!
Additionally, we always have a stock of roofing materials, so we can provideswift responses in emergencies!
Sorting and transporting waste materials in-house
The installation of solar panels often involves roofing work, generating various waste materials such as paint, wood, and metal.
By sorting and recycling waste materials, we can significantly cut waste disposal costs.
Exterior renovation dedicated showroom
In the showroom, not only can you have meetings, but you can also
check the actual foundation brackets for solar panels and see how they are installed on the roofing materials!
It is also possible to simulate the revenue and installation costs when introducing solar panels!
Since roofing and exterior wall work often accompany each other, we also provide samples of roofing materials and models that illustrate the structure, allowing for detailed explanations!
3.All Work Performed by Our Own Team
One of Kakeru Koumuten’s major strengths is all work performed by our own team.
By having a consistent system from inquiry to project completion, Kakeru Koumuten can provide high-quality roof renovations at reduced costs.
Additionally, one representative will handle everything from the estimate to the completion of the work.
Since the same person will manage sales and construction, smooth communication is possible.
We can perform consistent in-house work from temporary scaffolding installation to exterior wall painting and roof renovations!
4. Various Permits and Skilled Workers
We have obtained construction industry permits 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, our solar panel installation work comes with our own workmanship warranty (leakage warranty)!
(The workmanship warranty for solar panel installation is 10 years. Depending on the condition of the roof before installation, we may not be able to provide a warranty unless roof renovation is performed. The workmanship warranty is separate from the manufacturer’s product warranty, and the scope and conditions vary depending on the warranty content.)
Aftercare maintenance is available annually, and we send out notification DM each year.
If you have any questions about the warranty, please click on the image above!
6. Flexible and Prompt Response
We are equipped to handle various roof troubles and situations.
Even if we cannot access the roof at high places, we can respond using a drone!
During leakage investigations, we can also conduct inspections using a thermal imaging camera.
If the power generation of the solar panels decreases due to dirt, we can also perform cleaning with a specialized brush.
We will respond according to the customer’s wishes.
7. Human Resource Development
To improve skills, we create various roof models and conduct practical training.
Since the construction methods vary depending on the shape and slope of the roof, we regularly provide technical training so that each staff member can handle various cases.
8. Creation of Clear Materials and Simulations
At Kakeru Koumuten Co., Ltd., in addition to “estimates”, “layout diagrams”, and “power generation simulations”, we also provide a “solar installation guidebook” and a “profit and loss simulation” that takes into account loan interest rates and electricity costs.
The profit and loss simulation can be created for projected cumulative profits and losses over 20 to 30 years.
Even customers who are not familiar with solar installations will find 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.
Confirming “whether it is okay to install them directly on the current roof” before installation 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 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 shading of the roof | The orientation and slope of the roof surface, as well as shading from neighboring houses, trees, and utility poles, can affect power generation. We will create a layout diagram from the drawings and on-site, and you can check it with the power generation simulation. |
| 4. Shape of the roof and installable area | The number of panels (installation capacity) that can be placed depends on the shape and size of the roof. The number of panels that can be installed varies by panel 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 method involves drilling holes in the roofing material for fastening or using brackets to secure the roofing material. The fastening method varies by technique, so please check the waterproofing treatment method for 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, replacing with 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 also affects 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 treatment of fixing parts, cracks and deterioration of slate, condition of the substrate. If deterioration is advanced, consider roof overlay 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 secure to the substrate) | Type and condition of tiles, substrate, load-bearing capacity. Depending on the investigation results, there may be methods to replace with lightweight 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, construction 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 plan to renovate the roof 10 to 20 years after installation, there will be additional costs for removing and reinstalling solar panels. If the roof is deteriorating, it may be more cost-effective in the long run to renovate to a highly durable roofing material before installation.
Kakeru Koumuten is strong 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 Zama City, Kanagawa Prefecture
PotentialSubsidies and Grants in Zama City, Kanagawa Prefecture
If you introduce solar panels or storage batteries in Zama City, you may be eligible for programs from “the national government,” “Kanagawa Prefecture,” and “Zama City.”
The following information is based on the official pages of each program as of October 6, 2026. The application status may change depending on the budget and application period, 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 |
|---|---|---|---|
| Zama City “Smart House Related Equipment Installation Subsidy” (Solar Power Generation & Lithium-ion Storage Battery) | Residents within the city (must not have any tax arrears. Please check the city’s official page for detailed eligibility). Must be unused and not leased. Solar power must be equipment based on a supply contract with the power company with a maximum output of less than 10kW, and storage batteries must be products eligible under the Ministry of the Environment’s ZEH support project. Application must be submitted at least 14 days before the start date of installation work. | Solar Power: 10,000 JPY/kW (up to 40,000 JPY) Storage Battery: Flat rate of 40,000 JPY |
Applications are being accepted from April 1, 2026 (first-come, first-served; will end once the budget is reached) Against a budget of 4,000,000 JPY, the remaining budget as of September 30, 2026, is 903,000 JPY |
| Kanagawa Prefecture “Fiscal Year 2026 Kanagawa Prefecture Residential Solar Power Generation & Storage Battery Installation Subsidy” | For single-family homes or multi-family residences in the prefecture, it is required to install both solar power generation and storage batteries in a house that ensures seismic performance. The application must be made by the individual, and construction must begin after the grant decision. | Solar Power: 70,000 JPY/kW Storage Battery: 150,000 JPY/unit |
Phase 1: May 11, 2026 – June 30, 2026 Phase 2: September 7, 2026 – September 30, 2026 (first-come, first-served) Phase 2 has reached its application deadline. Please check the prefecture’s official page for future recruitment. |
| National “DR Home Storage Battery Project” (Fiscal Year 2025 Supplement) | Newly introduce a home storage system that can be utilized for DR (demand response) with registered products. | Calculated based on an initial effective capacity of 1 kWh at 34,500 JPY (subsidy rate within 30% & maximum of 600,000 JPY per application). | As of May 29, 2026, the budget has been reached, 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 just the installation of storage batteries. Solar panels are not included as eligible facilities. | Storage Battery: 96,000 JPY/unit | Ends once the budget cap is reached. Please check the official site for application status. |
| Kanagawa Prefecture “Fiscal Year 2026 Kanagawa Prefecture Self-Consumption Type Renewable Energy Installation Subsidy” | Corporations and individual business owners filing blue returns (individual residences are not eligible). Solar power must have a generation output of 10 kW or more, for business facilities, and equipment not certified under FIT/FIP. | Solar Power: 80,000 JPY/kW, etc. Storage System: 50,000 JPY/kWh (up to 5,000,000 JPY) |
Recruitment ended on September 3, 2026 (application amount reached the budget amount). |
In Zama City, applications for subsidies must be submitted at least 14 days before the start date of the installation work, and will end once the budget is reached on a first-come, first-served basis. As of September 30, 2026, the remaining budget is reported to be 903,000 yen, so please check the application status early. The subsidy for housing in Kanagawa Prefecture requires the start of construction after receiving the “grant decision”, and the application deadline for the second phase of the Reiwa 8 fiscal year has passed. According to the city’s official page, it is possible to combine the city’s subsidy with national and prefectural subsidies, but it is important to confirm the individual conditions at the city’s office. It is not guaranteed that a grant will be awarded upon application, so please confirm before contracting and starting work.
At Kakeru Koumuten Co., Ltd., we will guide you on the eligibility conditions for each system after confirming them.
Zama City “Smart House Related Equipment Installation Subsidy” (Solar Power Generation and Lithium-ion Storage Batteries)
Zama City provides a subsidy for the installation of solar power generation systems and lithium-ion storage batteries for residential properties. Conditions include being a resident of the city and having no delinquency in city taxes.
The subsidy amount is 10,000 yen per kW for solar power generation (up to 40,000 yen) and a fixed amount of 40,000 yen for lithium-ion storage batteries. Solar power must have a maximum output of less than 10 kW, and the storage battery must be a product eligible for the Ministry of the Environment’s ZEH support project, and applications for storage batteries only are also accepted.
Applications are being accepted from April 1, 2026, and against a budget of 4 million yen, the remaining budget as of September 30, 2026, is 903,000 yen. The program will end once the budget is reached, and applications must be submitted at least 14 days before the start date of the installation work. It is important to confirm the timing of the work and the order of applications before contracting.
👉 Click here for Zama City’s official page
National Subsidy “DR Home Storage Battery Project (Support Project for Home Storage Systems for DR Resource Introduction)”
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 introducing new storage systems of registered products that can be utilized for demand response (DR), and in the fiscal year 2025 supplementary budget, 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 contracts or orders made before the grant decision are not eligible.
However, the fiscal year 2025 supplementary budget reached its application amount on May 29, 2026, and the public offering has ended (the previous fiscal year’s supplementary budget also ended on July 2, 2025). Applications are currently not possible, so 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 official site of the DR Home Storage Battery Project
Kanagawa Prefecture “Reiwa 8 Year Subsidy for Residential Solar Power Generation and Storage Battery Installation Costs”
In Kanagawa Prefecture, subsidies are provided for those who install both “solar panels” and “storage batteries” in their homes.
The subsidy amounts are 70,000 yen per kW of solar power generation output and 150,000 yen per storage system.
For example, if you install a 4kW solar panel and one storage battery, the calculation for the subsidy amount would be 4kW × 70,000 yen + 150,000 yen = 430,000 yen.
Conditions include that the storage system must be a registered product, if construction begins before the grant decision, it will be ineligible, and the application must be made by the individual (applications by contractors on behalf of the individual are not allowed). The eligible homes must also ensure seismic performance. Please check each subsidy program for compatibility with other subsidy systems, as this may vary.
For Reiwa 8 Year, the first application period (May 11 – June 30) and the second application period (September 7 – September 30, first-come-first-served) have been conducted, and the second period has reached its deadline. For future recruitment, please check the official page of Kanagawa Prefecture.
👉 Click here for the official page of Kanagawa Prefecture
Kanagawa Prefecture “Reiwa 8 Year Subsidy for Self-Consumption Type Renewable Energy Installation Costs” (for businesses)
Kanagawa Prefecture also offers subsidies for businesses that install “self-consumption type” facilities that use electricity generated by solar panels.
Eligible applicants are corporations or individual business owners filing blue returns, and installations in individual residences are not eligible.
Conditions include that solar power generation must have an output of 10kW or more, supply power to business facilities within the prefecture, and not be equipment certified under FIT/FIP.
The subsidy amount is 80,000 yen per kW of solar power generation and 50,000 yen per kWh for the accompanying storage system (with a maximum of 5 million yen).
As the application amount reached the budget amount for Reiwa 8 Year, the recruitment was closed on September 3, 2026.
Businesses considering the installation of solar panels on commercial buildings in Zama City should check the official page of Kanagawa Prefecture for the next recruitment.
👉 Click here for details
Solar Panel Installation and Storage 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.
Considerations for Installation Capacity (kW) and Battery Capacity (kWh)
The installation capacity of solar panels is determined by “Output of One Panel (W) × Number of Panels”, with the unit being kW (kilowatt). Batteries are compared based on the amount of electricity they can store, represented in kWh (kilowatt-hour).
The amount of kW that can be placed on the roof varies for each house based on the roof’s shape, orientation, and size. At Kakeru Koumuten, we create layout diagrams from blueprints and on-site surveys to present the installation capacity.
On our pricing page, we list solar panel installation costs as approximately 800,000 JPY to 1,200,000 JPY for 3 to 5 kW, and 1,200,000 JPY to 1,900,000 JPY for 6 to 10 kW. (These are just estimated amounts and may vary based on wiring length, scaffolding area, existing roofing materials, panel layout, etc.)
▶ Installation Menu | Costs for Solar Panel and Storage Battery Installation
Items to Confirm in the Estimate (Cost Check)
When comparing estimates, it is common to compare different capacities and equipment based solely on price. 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 storage battery together. |
| 3. Storage Battery | Manufacturer, model number, capacity (kWh), range usable during power outages (entire house or specific circuits), installation location. |
| 4. Mounting Frame and Hardware | Name of hardware suitable for roofing materials and method of fixing (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, and whether there is a monitor to check power generation. |
| 6. Roof Reinforcement and Waterproofing | Details of waterproofing treatment at fixing points, and whether necessary roof repairs and substrate reinforcements are included. |
| 7. Applications | How much support is included for applications to the power company, feed-in tariff (FIT) certification applications, 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 double-counted. |
| 9. Removal and Disposal | Whether the removal of existing solar thermal water heaters or old panels, and disposal costs for waste materials are included. |
| 10. Tax Classification and Warranty | Whether prices are tax-inclusive or exclusive, conditions under which additional costs may arise, and details and duration of manufacturer and workmanship warranties. |
If the capacities differ, both the price and power generation will change. Kakeru Koumuten Co., Ltd. welcome comparisons, so if you bring estimates from other companies, we will explain the differences item by item!
Self-Estimate and Profit Simulation for Solar Power Generation
With the simulator above,
you can get an estimated quote and income 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 estimated quote and income simulation!
*The simulation results are estimates. Actual income 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)!
Examples of Solar Panel Installations
| 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 catching 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 |
| About 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 can 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 Company in Zama City, Kanagawa Prefecture
There are many solar panel installation companies that serve Zama City, Kanagawa Prefecture, and you may be unsure which company to choose.
Therefore, when requesting solar panel installation or battery storage installation work, let’s check the following 4 points.
● Have extensive knowledge not only about solar panels but also about roofs
● Confirm the presence of warranties and aftercare maintenance
● Obtain estimates from multiple companies (3 companies as a guideline)
● Check if they provide support for subsidy applications
By confirming the above 4 points, you will be able to choose a reliable company.
Knowledge about roofs as well as solar panels
Defective installation of solar panels can sometimes be caused by a lack of knowledge and verification regarding roofs and waterproofing.
While knowledge about solar panels is certainly important, understanding the roof and waterproofing at the installation site of the solar panels is also crucial.
⚠︎Examples of troubles caused by insufficient verification of roofs and waterproofing
・Solar panels were installed on a severely deteriorated roof, resulting in leaks
・Solar panels were installed on a roof with a short lifespan, requiring remodeling for removal and reinstallation within a few years
・Misjudgment of the type of waterproofing led 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 company, 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.
While the solar panels and battery storage units come with a manufacturer’s warranty, also check for the presence of a workmanship warranty in case leaks occur after installation!
For companies that offer a workmanship warranty, if leaks occur after installation, they may be able to respond under the warranty if 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 damages on the roof may occur in areas that are not visible, so there is a possibility that customers may not notice them.
By conducting inspections during after-sales maintenance, we can easily prevent significant repairs or failures by detecting abnormalities early!
Kakeru Koumuten Co., Ltd. provides 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, we may not be able to provide a warranty without performing roof renovations.)
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!
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 construction content, costs may vary, and warranties and after-sales services may differ.
Additionally, obtaining multiple estimates makes it easier to negotiate prices.
To request services from your preferred contractor at a lower price, we recommend obtaining estimates from multiple contractors.
When comparing estimates, please check carefully for:
“Verification of estimate items”
“Types of solar panels”
“Warranties and after-sales services”
Make sure to compare these details closely! If the quality of auxiliary materials is low or if steps are skipped, costs can be reduced, so avoid making decisions based solely on price!
▶ Go to “Breakdown of Installation Capacity and Equipment/Construction Costs” in this article
Check if they provide support for subsidy applications
Subsidies may be 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.
For systems like the Kanagawa Prefecture housing subsidy, where contractors cannot apply on behalf of the client, it is reassuring to have a contractor who can support the preparation of necessary documents and the flow of procedures.
Complete the procedures specified for each system (for the prefectural housing subsidy, this means obtaining a grant decision) before proceeding with the construction!
In the case of the prefectural housing subsidy, after the construction is completed, a performance report must be submitted, and the subsidy will be granted after a review! (The flow of procedures varies by system.)
▶ To “Subsidies and Grants That May Be Applicable in Zama City” within this Article
Benefits of Introducing Solar Power Systems
The benefits of introducing solar panels are summarized in the following 5 points!
Benefit 1: Economic Advantages
The biggest advantage of introducing solar panels is the economic benefit!
Although the selling price of electricity has decreased compared to 10 years ago, by consuming the electricity generated, you can reduce the amount of electricity purchased from the power company and gain benefits!
As electricity prices rise, the ability to cover consumption with solar power becomes attractive!
If you plan to use the generated electricity at night, the installation of a storage battery is essential!
For residential use (under 10kW), the selling price (FIT) for electricity generated from October 2025 onwards is set at “24 yen/kWh for the first 4 years, and 8.3 yen/kWh from the 5th to the 10th year.” The same price will apply in the 2026 fiscal year. After the 5th year, it tends to be more advantageous to use it at home (self-consumption), so combining it with a storage battery is also an option.
👉 Ministry of Economy, Trade and Industry | For purchase prices, periods, etc., click here
Benefit 2: You Can Utilize Subsidies!
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 Zama City, there may be subsidies available from the city or Kanagawa Prefecture, so please check the latest application status.
Benefit 3: Environmentally Friendly!
Solar power generation has low carbon dioxide emissions and reduces 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.)
Benefit 4: Heat Insulation Effects Can Be Expected!!
By installing the panels on the roof or rooftop, they block direct sunlight from hitting the roof.
Especially in summer, this can help reduce the temperature of the roof, providing a heat shielding effect!
(Note that 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 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.
(Note that the devices, output, and duration that can be used during a power outage vary depending on the model and wiring method.)
What points should be noted when introducing solar power generation?
Next, we will explain the “three points to note” when installing solar panels!
Point 1 Maintenance costs can be incurred
A maintenance cost that is often overlooked 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 reattaching 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 is reassuring to ask for a simulation that considers maintenance costs before introducing solar panels!
Point 2 The risk of leaks increases depending on the roofing material
The fixing methods for slate roofs and tile roofs vary by construction method, but in methods that fix the hardware to the roofing material or substrate with screws, waterproofing of the fixed parts is crucial.
In methods that involve making holes in the roof, the risk of leaks inevitably arises.
Of course, we will ensure proper waterproofing, but if you are concerned about making holes, replacing the roofing material with a metal roof and fixing the solar panels using the catch method is also an option. (The catch method has compatibility conditions between the roofing material and hardware, and it cannot be used with all metal roofs.)
Catch-type base metal fittings for horizontal metal roofs
Note 3: The roof will become heavier
Since solar panels will be installed, the roof will become heavier. After investigating the existing roof, substrate, and load-bearing capacity, one option may be to replace it with a lighter roof 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 Method 1: Compare based on total roof output
When installing solar panels on the roof, it is important to consider how much power can be generated in a limited area, and generating more power is always better!
Solar panels come in various sizes depending on the manufacturer, and their outputs differ.
For example, a 350W output panel and a 400W output panel may seem that the higher output panel 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 numbers of panels that can be installed 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 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 power generation (kWh) will vary depending on conditions such as roof orientation, slope, and shading.
Choosing Method 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 benchmark figure for the warranty and does not indicate the actual degradation rate or power generation itself.
By not deciding solely based on initial output and considering the degradation rate, you can choose solar panels without regrets!
Choosing Method 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!
A longer warranty is always better, so let’s check the warranty periods and conditions of the manufacturers you are considering!
Frequently Asked Questions about Solar Power and Storage Battery Installation in Zama City
We have compiled frequently asked questions from customers considering the installation of solar panels and storage batteries in Zama City. (Tap to open the answers)
How much does it cost to install solar panels and storage batteries in Zama City, Kanagawa Prefecture?
The cost varies depending on the installation capacity, equipment, and condition of the roof. 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 costs by capacity are published on 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 Zama City?
As of October 6, 2026, Zama City’s “Smart House Related Equipment Installation Subsidy” (10,000 yen/kW for solar power, up to 40,000 yen; 40,000 yen for lithium-ion storage batteries) is currently accepting applications on a first-come, first-served basis (the remaining budget as of September 30, 2026, is 903,000 yen). The Kanagawa Prefecture subsidy (70,000 yen/kW for solar power, 150,000 yen per unit for storage batteries) is approaching the application deadline for the second term of fiscal year 2026, and the national DR household storage battery project has ended its public recruitment.
Since the application status may change, please refer to the subsidy and grant section and consult with us before signing a contract.
Can I apply for subsidies even after the construction is completed?
For many programs, procedures are required before construction. The Zama City subsidy requires applications to be submitted “14 days before the construction start date,” and the Kanagawa Prefecture subsidy requires “construction to start after the grant decision,” so if you install it first, you may be excluded from eligibility.
The order of procedures varies by program, so please confirm before signing a contract or 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 first. 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 is a specialized exterior renovation company strong in roofing work, so we will check the condition of the roof before installation and propose methods such as roof overlay (cover method) or replacement if deterioration is advanced.
The 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, the cost for 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 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 in Kanagawa Prefecture requires the simultaneous introduction of solar panels and storage batteries, while the subsidy in Zama City can be applied for with just the storage battery (the storage battery must be a product eligible for the Ministry of the Environment’s ZEH support project). You can compare “solar panels only” and “solar panels + storage battery” through a financial simulation.
How many kW can be installed on my roof? Is it okay for north-facing roofs or those 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 generation simulation.
Zama City has varied topography, including hilly areas, plateaus, and lowlands, and the shading from neighboring houses, trees, and elevation differences varies from house to house. You can check the expected generation amount through the generation simulation.
How long will the construction take?
In the above construction example (solar panels 4.3 kW + storage battery), it took about 3 days. The duration may vary depending on whether roof work is done simultaneously and the shape and installation capacity of the roof.
Additionally, please note that there will be a separate period for applying for subsidies and to the power company, so please consult us as soon as possible.
What is the current selling price (FIT)?
For residential use (under 10 kW), the selling price 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, with the same price applied for the 2026 fiscal year.
The idea is to recover initial costs more quickly in the first 4 years and then focus on self-consumption. Kakeru Koumuten provides a financial simulation that considers loan interest rates and electricity costs.
Can you handle maintenance and inspections after installation?
Yes, we can. Kakeru Koumuten sends out annual after-service maintenance DM notices and visits customers who wish to have inspections. We can also clean solar panels with a special brush if the generation amount decreases due to dirt.
It can be difficult to check areas on the roof by yourself, so please feel free to consult us if you have any concerns.
Can you renovate a roof that already has solar panels installed?
Yes, we can. Since Kakeru Koumuten can remove and reinstall solar panels in-house, we will handle the process of removing the panels, performing roof overlay (cover method) or re-roofing, and reinstalling them consistently. The removed panels can be stored in our warehouse.
For costs, please refer to the solar panel removal and water heater removal pricing page.
If you are looking for a solar panel installation contractor in Zama City, please consult Kakeru Koumuten
Our company handles a wide range of exterior renovations, including solar panel installations, roofing work, and exterior wall work in Zama City, Kanagawa Prefecture.
We receive requests from many customers, including renovation companies and real estate agencies, who have contacted us!
Kakeru Koumuten promises “high-quality renovations at low costs”, 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 and replacement work but also partial roof repairs, exterior painting, and exterior cover methods.
We are also happy to handle small jobs such as partial repairs and rain gutter cleaning!
In urgent cases such as leak repairs, we may be able to provide temporary measures without setting up scaffolding, as long as safety can be ensured, so please consult us!
“I want to know about recommended solar panels”, “I want to keep costs as low 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 our customers’ shoes and will 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 construction!
We are confident, so we welcome competitive quotes!
Estimates are completely free, and if we are found to be inferior to other companies, you are free to decline!
Characteristics of Zama City, Kanagawa Prefecture, and Points for Solar Construction
Zama City is located in the central part of Kanagawa Prefecture, and according to the official city page, the area is approximately 17.57 km², with a city area of about 5.3 km east to west and 4.0 km north to south. The terrain is divided by the Zama Hills running north to south, with the Sagamino Plateau on the east side and the alluvial lowlands along the Sagami River on the west side.
We have summarized the characteristics of Zama City and points to consider when installing solar panels and storage batteries below. (Tap to open)
View the characteristics of Zama City and points for solar construction
■ A terrain mixed with hilly areas, plateaus, and lowlands. Shadow checks should be done for each individual house.
Geography and Location of Zama City (Official City Site) introduces that Zama City has the Zama Hills running north to south, with the Sagamino Plateau to the east and the alluvial lowlands along the Sagami River to the west, with an elevation ranging from approximately 24m to about 89m. The city area is compact, but the locations of residential areas vary between hilly, plateau, and lowland regions, and the appearance of surrounding buildings, trees, and shadows due to elevation differences changes from house to house. At Kakeru Koumuten, we create layout diagrams based on blueprints and the actual site conditions, allowing you to confirm through power generation simulations.
■ Confirm Installation Locations for Equipment in Lowland Residences
The western side of the city corresponds to the lowlands along the Sagami River. When deciding on the installation locations for storage batteries and power conditioners, it is reassuring to check the flood risk for your residence on the hazard map. We will propose installation locations considering wiring routes and ease of inspection.
■ Confirm Fixing Methods According to Roof Types
Not limited to Zama City, the fixing methods for solar panels vary depending on roofing materials such as slate, tiles, and metal roofs. In methods that fix brackets to the roof, waterproofing treatment for the fixed parts is crucial, so we will confirm the combination of roofing materials and methods during the estimate.
■ City Subsidies are First-Come, First-Served. Applications Must Be Made 14 Days Before Construction Starts
Zama City’s Smart House Related Equipment Installation Subsidy (Official City Site) has been accepting applications since April 1, 2026, and as of September 30, 2026, the remaining budget is reported to be 903,000 yen (total budget of 4 million yen). The program will end once the budget is reached, and applications must be made 14 days before the start date of the installation work. It is important to confirm the timing of the work and the order of applications before signing the contract.
■ Check Roof Condition According to Age of the Building
For residences that have been built for several years, it is important to check the condition of roofing materials and substrate before installing solar panels. Depending on the condition of the roof, installing them simultaneously with roof renovations can reduce future costs for removing and re-installing solar panels.
■ Be Aware of Roof Dirt Such as Fallen Leaves and Dust
If dirt such as fallen leaves and dust accumulates on the roof, it may affect power generation. Kakeru Koumuten can also handle solar panel cleaning with specialized brushes and rain gutter cleaning.
Our company is based in Kanagawa Prefecture and has undertaken many exterior construction and solar projects in Zama City.
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 urgent issues!
Service Area in Zama City, Kanagawa Prefecture
Kakeru Koumuten accepts requests throughout Kanagawa Prefecture and the entirety of Tokyo.
List of Areas in Zama City, Kanagawa Prefecture
Iridani Nishi, Zama City / Iridani Higashi, Zama City / Kurihara, Zama City / Kurihara Chuo, Zama City / Komatsubara, Zama City / Sagamigaoka, Zama City / Sagamino, Zama City / Zama, Zama City / Nitta Juku, Zama City / Sobudai, Zama City / Tachinodai, Zama City / Nishikurihara, Zama City / Higashihara, Zama City / Hibarigaoka, Zama City / Hirono Daisan, Zama City / Midorigaoka, Zama City / Minamikurihara, Zama City / Myouou, Zama City / Yotsuya, Zama City
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・Trust Kakeru Koumuten for exterior renovations in Zama City, Kanagawa!
・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! Introducing features and selection tips!
・What are the installation costs for solar power generation? Comprehensive tips to reduce costs!
・What are the best locations for solar power installation? Key points for site selection!
・Check out our solar power generation 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!
