Leave Your Solar Panel Installation Work in Izumi, Yokohama City to Kakeru Koumuten Co., Ltd.!
For solar panel and battery installation in
Izumi Ward, Yokohama,
trust Kakeru Koumuten!
Kakeru Koumuten is a specialized exterior renovation company headquartered in Aoba Ward, Yokohama.
As a company strong in roofing work, we are entrusted withsolar panel and battery installation considering roofing and waterproofing!
“How to choose a solar panel contractor in Izumi Ward”
“Costs for solar panel and battery installation”
“Subsidies available for solar system installation in Izumi Ward”
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!
Table of contents (tap to open/close)
- Reasons Why Kakeru Koumuten Is Chosen for Solar Panel Installation in Izumi Ward, Yokohama
- Roof Inspection Before Installing Solar Panels
- Possible Subsidies and Grants Available in Izumi Ward
- Price List for Solar Panel and Storage Battery Installation
- Breakdown of Installation Capacity, Equipment, and Construction Costs
- Self-Estimate and Profit Simulation for Solar Power Generation
- Customer Testimonials
- Case Studies of Solar Panel Installations
- How to Choose a Solar Panel Installation Company in Izumi Ward, Yokohama
- 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 Izumi Ward
- If You’re Looking for a Solar Panel Installation Company in Izumi Ward, Contact Kakeru Koumuten
- Characteristics of Izumi Ward, Yokohama, and Key Points for Solar Work
- Service Area in Izumi Ward, Yokohama
Reasons Why Kakeru Koumuten Is Chosen for Solar Panel Installation in Izumi Ward, Yokohama
Regarding why we are entrusted with solar panel installation by customers in Izumi Ward, Yokohama,
one reason is that Kakeru Koumuten has a base in the same city of Yokohama,
but we also have strengths in solar panel installation that cannot be imitated by other companies, which has received high praise from many customers.
so we would be grateful 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 your expertise, so caution is necessary.
It’s 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
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 areas of Izumi Ward, where gentle hills and terraces spread out, our own scaffolding team will plan the scaffolding according to the site conditions.
Storage of materials in our large warehouse
We store roofing materials and paints, and we can also store removed solar panels.
By ordering a large quantity of materials at once, we canpurchase materials at a lower cost!
Additionally, we always have a stock of roofing materials, so we can providerapid response 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!
Simulations for potential earnings and installation costs when introducing solar panels are also available!
Since roofing and exterior wall work often accompany each other, we also provide samples of roofing materials and models that explain 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 roofing renovations at reduced costs.
Additionally, one representative will handle everything from the estimate to project completion.
Since the same person will be in charge, whether it’s sales or construction management, smooth communication is ensured.
We can perform consistent in-house work from temporary scaffolding installation to exterior wall painting and roofing renovations!
4. Various Permits and Skilled Workers
We have obtained construction industry permits as well as permits for industrial waste collection and transportation!
We also have nationally certified sheet metal and painting technicians on staff, giving us confidence in our construction techniques.
We are capable of handling large-scale roofing projects such as those for 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 remodeling is performed. The workmanship warranty is separate from the manufacturer’s product warranty, and the scope and conditions vary depending on the warranty details.)
Aftercare maintenance is available annually, and we send out notification DM each year.
If you have any questions about the warranty, please click on the image above!
6. Flexible and Prompt Response
We are equipped to handle various roof troubles and situations.
If you cannot access the roof at high altitudes, we can utilize a drone for inspections!
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
We create various roof models for skill enhancement and conduct practical training.
Since the installation methods change 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., we provide not only “estimates,” “layout diagrams,” and “power generation simulations” but also a “solar installation guidebook” and a “profit and loss simulation” that takes into account loan interest rates and electricity costs.
The profit and loss simulation can be created for projected cumulative profits and losses over 20 to 30 years.
Even customers who are not familiar with solar installations will find our materials easy to understand, including important points and potential drawbacks!
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 safe to install them directly on the current roof 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 substrate and waterproof sheet | If the sheathing or roofing (waterproof sheet) beneath the roofing material is damaged, it will 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, will 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 the size of the panels, 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 or securing it with brackets. 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 added 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 locations for the power conditioner and storage battery, as well as the wiring route to the distribution board. The length of the wiring will also affect costs. |
Securing Methods and Checkpoints by Roofing Material
| Roof Material | Main Fixing Method | Pre-Installation Check Points |
|---|---|---|
| Slate Roof | Varies by method (methods such as fixing brackets to the roof material and substrate with screws, etc.) | Waterproofing treatment 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 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, it may be more cost-effective in the long run to renovate to a highly durable roofing material before installation.
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 Izumi Ward, Yokohama City
Potential Subsidies and Grants in Izumi Ward, Yokohama City, Kanagawa Prefecture
When introducing solar panels and storage batteries in Izumi Ward, there is a possibility of being eligible for programs from the “National Government,” “Kanagawa Prefecture,” and “Yokohama 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, so please check the latest information before contracting or starting work.
Eligibility Conditions and Application Period for Subsidy Programs
| Program | Main Eligibility Conditions | Subsidy Amount | Application Period & Status |
|---|---|---|---|
| Yokohama City “Yokohama Green Energy Partnership Project (YGrEP)” Reiwa 8 Fiscal Year | Yokohama residents installing eligible equipment at their homes. Solar power must be newly installed, and either a storage battery, eco-cute, electric vehicle, etc. must be installed simultaneously or already installed. | Solar power: 15,000 JPY/kW (up to 4 kW) Storage battery: 120,000 JPY per case (Refund via cashless points, etc.) |
Participation & Installation Support Application: June 15, 2026 – December 25, 2026 (Application before installation) Installation Completion Application: By January 22, 2027 Ends when the budget limit is reached. |
| Kanagawa Prefecture “Reiwa 8 Fiscal Year Kanagawa Prefecture Residential Solar Power Generation & Storage Battery Installation Subsidy” | Installation of both solar power generation and storage battery in residential properties within the prefecture. Applications must be made by the individual, and construction can begin after the grant decision. | Solar power: 70,000 JPY/kW Storage battery: 150,000 JPY per unit |
Phase 1: May 11, 2026 – June 30, 2026 Phase 2: September 7, 2026 – September 30, 2026 (first-come, first-served) Phase 2 is nearing its application deadline. Please check the prefecture’s official page for further recruitment. |
| National “DR Household Storage Battery Project” (Reiwa 7 Fiscal 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 1 kWh at 34,500 JPY (subsidy rate within 3/10; maximum 600,000 JPY per application). | As of May 29, 2026, the budget has been reached, and applications are no longer accepted (currently not available for application). |
| National “Mirai Eco Housing 2026 Project” (Renovation) | Storage batteries are one of the eligible facilities, but they must be combined with essential works such as insulation renovations of windows (openings) and structures; applications cannot be made for just the installation of storage batteries. Solar panels are not included as eligible facilities. | Storage battery: 96,000 JPY per household | Ends when the budget limit is reached. Please check the official site for application status. |
| Yokohama City “Solar Power Generation Installation Support Subsidy” | Small and medium-sized enterprises and individual business owners within Yokohama City (residential use is not eligible). There are conditions for the target audience and equipment, such as being self-consumption type equipment. | Solar power + storage system: 100,000 JPY/kW (up to 5,000,000 JPY) Solar power only: 80,000 JPY/kW (up to 4,000,000 JPY) |
May 1, 2026 – October 30, 2026, 5 PM (first-come, first-served until budget limit is reached). |
| Kanagawa Prefecture “Reiwa 8 Fiscal Year 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 10kW or more, facilities for business use, equipment not certified under FIT/FIP, etc. | Solar power: 80,000 JPY/kW, etc. Storage system: 50,000 JPY/kWh (maximum 5,000,000 JPY) |
Application period ends on September 3, 2026 (when the application amount reaches the budget amount) |
YGrEP requires a “Participation and Introduction Support Application” before installation, while Kanagawa Prefecture’s residential subsidies require not only application acceptance but also “construction to begin after receiving the grant decision”. If you start installation or construction beforehand, you will be ineligible. The prefectural residential subsidy is granted after completion of construction and submission of a performance report and review. The order of procedures varies by program, and applying does not guarantee a grant, so please confirm before contracting or starting construction.
At Kakeru Koumuten Co., Ltd., we will guide you on eligibility conditions and business requirements for each program after confirming them.
National Subsidy “DR Home Storage Battery Project (Support Project for Home Storage System Installation 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 newly introducing registered storage systems that can be utilized for demand response (DR). In the fiscal year 2025 supplementary budget, the subsidy amount was determined based on a standard amount of 34,500 JPY per initial effective capacity of 1kWh, with a subsidy rate of up to 30% and a maximum of 600,000 JPY per application. There are conditions such as being ineligible for items contracted or ordered before the grant decision.
However, the fiscal year 2025 supplementary budget reached its application amount on May 29, 2026, and the public recruitment has ended (the previous fiscal year 2024 supplementary budget also ended on July 2, 2025). Applications are currently not possible, so please check the official website for future public recruitment.
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 “Fiscal Year 2026 Kanagawa Prefecture Residential Solar Power Generation and Storage Battery Installation Subsidy”
Kanagawa Prefecture provides subsidies for those who install both “solar panels” and “storage batteries” in residential properties.
The subsidy details are 70,000 JPY per 1kW of solar power generation and 150,000 JPY per storage system.
For example, if you install a 4kW solar panel and one storage battery, the subsidy amount would be calculated as 4kW × 70,000 JPY + 150,000 JPY = 430,000 JPY.
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 (substitute applications by contractors are not allowed). It is also possible to combine this with YGrEP in Yokohama City.
In the Reiwa 8 fiscal year, the first phase (from May 11 to June 30) and the second phase (from September 7 to September 30, first-come-first-served) are being accepted, and the second phase has reached its application deadline. For future recruitment, please check the official Kanagawa Prefecture page.
👉 Click here for the official Kanagawa Prefecture page
Kanagawa Prefecture “Reiwa 8 Fiscal Year Kanagawa Prefecture Subsidy for Self-Consumption Type Renewable Energy Introduction” (for businesses)
Kanagawa Prefecture is also implementing a subsidy for businesses that introduce “self-consumption type” facilities that use electricity generated by solar panels.
Eligible applicants are corporations or individual business owners who file blue returns, and individual residential installations are not eligible.
Conditions include that the solar power generation must have an output of 10 kW or more, supply electricity to business facilities within the prefecture, and not be equipment certified under FIT or FIP.
The subsidy amount is 80,000 yen per kW for 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 the Reiwa 8 fiscal year, applications were closed on September 3, 2026.
Businesses considering the installation of solar panels on commercial buildings in Izumi Ward should check the official Kanagawa Prefecture page for the next recruitment.
👉 Click here for details
Yokohama City “Subsidy for Solar Power Generation Introduction” (for businesses)
Yokohama City is implementing a system to subsidize part of the introduction costs for small and medium-sized enterprises and individual business owners within the city for solar power generation equipment and other installations.
Residential solar power generation is not eligible, and for households, the YGrEP mentioned below serves as the contact point. Businesses that install solar panels on stores, offices, factories, etc., in Izumi Ward may have the possibility to utilize this, but simply running a business from home does not guarantee eligibility. It is necessary to confirm the requirements for small and medium-sized enterprises and individual business owners, as well as that the equipment is of the self-consumption type (equipment aimed at selling electricity is not eligible).
The subsidy amount is 100,000 yen per kW when introducing both solar power generation and storage systems simultaneously (maximum of 5 million yen), and 80,000 yen per kW for solar power generation only (maximum of 4 million yen).
The application period for the Reiwa 8 fiscal year is from May 1, 2026, to October 30, 2026, at 5 PM, on a first-come-first-served basis until the budget limit is reached. Installation of equipment and commencement of construction must occur after the grant decision date.
For detailed conditions and application methods, please check the official website of Yokohama City.
👉 Click here for the official Yokohama City page
Yokohama City “Reiwa 8 Year Yokohama Green Energy Partnership Project (YGrEP)”
Yokohama Green Energy Partnership (YGrEP) is a project aimed at achieving a decarbonized society.
In Yokohama City, households that participate in YGrEP and install eligible equipment (refer to the eligible equipment below) will receive cashless points and other rewards. Residents of Izumi Ward are also eligible.
◎Eligible Equipment and Reward Amounts◎
● Solar Power Generation Equipment (New Installation): 15,000 yen/kW (up to 4kW)
* It is a condition that either a storage battery, eco-cute, or electric vehicle is installed simultaneously or already installed.
● Storage Battery: 120,000 yen per unit
● Eco-Cute: 20,000 yen per unit
● Electric Vehicle/Plug-in Hybrid Vehicle (set with solar power generation equipment): 100,000 yen per unit
* It is a condition that the storage battery, eco-cute, or electric vehicle (set) is installed simultaneously with the solar power generation equipment or already installed.
● Electric Vehicle alone (without solar power generation equipment): 50,000 yen per unit
● Fuel Cell (EneFarm): 30,000 yen per unit
● Solar Heat Utilization System: 50,000 yen per unit
● V2H Charging and Discharging Equipment: 100,000 yen per unit
For example, if you install a 4kW solar panel and a storage battery simultaneously, the calculation for the reward amount will be 60,000 yen for solar power + 120,000 yen for storage battery = a total of 180,000 yen.
The application process is “Participation and Installation Support Application (before installation) → Equipment Installation → Completion Application”, and equipment installed before the installation support application is not eligible. The participation and installation support application for Reiwa 8 Year is from June 15, 2026, to December 25, 2026, and the completion application is until January 22, 2027, and will end as soon as the budget limit is reached.
If selling electricity, only the surplus that cannot be used at home is eligible, and submission of monitoring data such as annual power generation is also a condition. Additionally, only V2H charging and discharging equipment is eligible for points and other rewards for businesses.
For application methods, information on combining with national and Kanagawa Prefecture subsidy projects, point rewards, and more, please check the special site here for details and inquiries.
Solar Panel Installation & Battery Installation Price List
⇧Service Menu | For Costs Related to Solar Panel Installation & Battery Installation, Click Here
⇧Service Menu | For Costs Related to Solar Panel Removal & Water Heater Removal, Click Here
Breakdown of Installation Capacity, Equipment, and Construction Costs
The costs for solar panels and batteries should be checked separately for “Equipment Costs (Equipment Price)” 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 “the output of one panel (W) × number of panels”, with the unit being kW (kilowatts). The amount of electricity that can be stored in batteries is compared using kWh (kilowatt-hours).
The amount of kW that can be placed on the roof varies for each house depending on the shape, orientation, and size of the roof. At Kakeru Koumuten Co., Ltd., we create a layout diagram based on blueprints and on-site surveys to present the installation capacity.
On our pricing page, we list solar panels as approximately 800,000 yen to 1,200,000 yen for 3 to 5 kW, and 1,200,000 yen to 1,900,000 yen for 6 to 10 kW. (These are just approximate amounts and may vary based on wiring length, scaffolding range, existing roofing materials, and panel layout.)
▶ Installation Menu | Costs for Solar Panel Installation and Battery Installation
Items to Confirm in the Estimate (Cost Confirmation)
When comparing estimates, it is common to compare different capacities and equipment just by looking at the amounts. Please check if the following items are clearly stated in each company’s estimate!
| 1. Solar Panels | Manufacturer, model number, output of one panel (W), number of panels, total installation capacity (kW) are listed. |
| 2. Power Conditioner | Manufacturer, model number, capacity, number of units, installation location (indoor/outdoor). Also check if it is a type that controls together with the battery. |
| 3. Battery | Manufacturer, model number, capacity (kWh), range usable during a power outage (entire house or specific circuits), installation location. |
| 4. Mounting Frame and Hardware | Name of the hardware suitable for the roofing material and the method of securing it (whether it is a method that drills holes or a method that clamps to secure). |
| 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 for fixed parts, whether necessary roof repairs and substrate reinforcements are included. |
| 7. Applications | How much support is included for applications to the power company, certification applications for selling electricity (FIT), and subsidy applications. |
| 8. Scaffolding | Scope and quantity of scaffolding. If it is simultaneous with roof work or exterior painting, check that the same scope and quantity are not counted twice. |
| 9. Removal and Disposal | Whether the removal of existing solar water heaters or old panels and disposal costs for waste materials are included. |
| 10. Tax Classification and Warranty | Whether prices are inclusive or exclusive of tax, conditions under which additional costs may arise, and details and duration of manufacturer and workmanship warranties. |
If the capacities are different, the amounts and power generation will also change. Kakeru Koumuten Co., Ltd. welcome price comparisons, so if you bring estimates from other companies, we will explain the differences for each item!
Self-Estimate and Profit Simulation for Solar Power Generation
With the simulator above,
you can obtain a rough estimate and a financial simulation 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 a rough estimate and financial simulation!
*The simulation results are approximate. Actual financial results may vary based on assumptions such as electricity rates, self-consumption ratios, selling prices, and costs for equipment inspection or replacement.
Customer Feedback
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customer reviews
Asao-ku, Kawasaki City | We received reviews about the ridge cap and rain gutter replacement work!
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customer reviews
Kohoku-ku, Yokohama | We received reviews about the roof overlay (cover method)!
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customer reviews
Kohoku-ku, Yokohama | We Received Reviews About Exterior Painting!
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customer reviews
Hodogaya-ku, Yokohama | We received reviews about our exterior fence construction!
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customer reviews
Tsurumi-ku, Yokohama | We received reviews about roof and exterior wall painting, as well as metalwork and rain gutter replacement work!
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customer reviews
Higashiyamato City, Tokyo | We received reviews about exterior painting and roof overlay (cover method)!
Case Studies of Solar Panel 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 Arrangement |
| Fixed using catch type hardware gripping the horizontal metal roof (Catch Method) |
| Price Range |
| 2,200,000 JPY～2,300,000 JPY *Due to the subsidy being granted, the actual burden amount is approximately 1,000,000 JPY Estimated recovery period for construction costs: about 8 to 9 years (self-consumption) *The subsidy amount and recovery estimate are based on the system and calculations at the time of construction, and may differ under the current system. |
| Construction Period |
| Approximately 3 days |
| Completion Month |
| April 2025 |
| Inquiry Details |
| I am considering the installation of solar panels and storage batteries. I heard that subsidies are available, and I would like to know how much will be granted. |
Our Proposal
We visited to provide a quote and created a layout diagram for the solar panels from the drawings!
The layout diagram shows the arrangement of the 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 subsidies, so we explained this to the customer along with the quote!
How to Choose a Solar Panel Installation Contractor in Izumi Ward, Yokohama
There are many solar panel installation contractors available in Izumi Ward, Yokohama, 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 panels but also about roofs
● Confirm the presence of warranties and aftercare maintenance
● Obtain estimates from multiple contractors (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 contractor.
Knowledge about roofs as well as solar panels
Defective installation of solar panels can sometimes be caused by a lack of knowledge and verification regarding roofs and waterproofing.
While knowledge about solar panels is certainly important, understanding the roof and waterproofing at the installation site of the solar panels is also crucial.
⚠︎Examples of troubles caused by insufficient verification of roofs and waterproofing
・Installing solar panels on a severely deteriorated roof, leading to leaks
・Installing solar panels on a roof with a short lifespan, requiring renovations to detach and reattach the solar panels within a few years
・Misjudging the type of waterproofing and applying incorrect treatment, resulting in leaks
and more
When installing solar panels, understanding the condition and type of the existing roof allows you to avoid unnecessary expenses and 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 scope of coverage, exclusions, and cost conditions.
While the solar panels and battery storage units come with manufacturer warranties, it is also important to check for the presence of a workmanship warranty in case leaks occur after installation!
For contractors that offer workmanship warranties, if leaks occur after installation, they may be able to respond under the warranty, provided it is 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 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 detect issues early, making it easier to prevent significant repairs or failures!
Kakeru Koumuten Co., Ltd. provides a rain 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 unless a roof renovation is performed.)
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 work content, costs may vary, and warranties and after-sales services may differ.
Additionally, obtaining multiple estimates makes it easier to negotiate prices.
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 panels”
“Warranties and after-sales services”
Make detailed comparisons to make your judgment! If the rank 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, Equipment, and 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 Kanagawa Prefecture’s housing subsidies, where applications cannot be submitted by the contractor and must be done by the individual, 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 the prefectural housing subsidy, this means obtaining a grant decision) before proceeding with the construction!
For the prefectural housing subsidy, after the construction is completed, a performance report must be submitted, and the flow will go through a review before the grant is provided! (The flow of procedures varies by system)
▶ To “Subsidies and Grants That May Be Applicable in Izumi Ward” 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 Advantage
The biggest advantage of introducing solar panels is the economic benefit!
While the selling price of electricity has decreased compared to 10 years ago, you can gain benefits by reducing the electricity you buy from power companies through self-consumption of generated electricity!
As electricity prices rise, the ability to cover your consumption with solar power becomes attractive!
If you plan to use the generated electricity at night, installing a storage battery is essential!
For residential (under 10kW) selling prices (FIT), the price setting 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.” The same price will apply for the 2026 fiscal year. After the 5th year, it is often more advantageous to use it at home (self-consumption) rather than selling it, making the combination with a storage battery a viable 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 through subsidies is a significant advantage!
In the case of Izumi Ward, there may be eligibility for subsidies from Yokohama City’s YGrEP or Kanagawa Prefecture.
Benefit 3: Environmentally Friendly!
Solar power generation has low carbon dioxide emissions and can reduce dependence on fossil fuels, contributing to the mitigation of global warming.
Solar panels themselves do not produce noise or exhaust gases during the generation process, making them an environmentally friendly method of power generation. (However, devices such as power conditioners do have operational noise.)
Benefit 4: Expected Heat Insulation Effect!!
By installing the panels on the roof or rooftop, they block direct sunlight from hitting the roof.
Especially in summer, it 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: Power usage is possible 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 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 deteriorating, it is reassuring to remodel 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 request a simulation that considers maintenance costs before introducing solar panels!
Point 2: The risk of leaks increases depending on the roofing material
The fixing methods for slate roofs and tile roofs vary by construction method, but when using screws or other fasteners to secure the roofing material and substrate, waterproofing of the fixed parts becomes crucial.
If the method involves making holes in the roof, the risk of leaks inevitably arises.
Of course, we will ensure proper waterproofing, but if you are concerned about making holes, replacing the roofing material with a metal roof and securing the 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 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 capacity, replacing it with a lighter roof may also be an option if necessary.
How to Choose Solar Panels?
There are many manufacturers of solar panels, and their output and costs vary.
It is not simply a matter of “this manufacturer has the best solar panels”; it is important to choose solar panels that are suitable for your life plan and building!
Here are some points to consider when comparing solar panels!
How to Choose 1: Compare by Total Roof Output
When installing solar panels on the roof, it is important to know how much power can be generated in a limited area, and the more power generated, the better!
The size and output of solar panels vary by manufacturer.
If you have a 350W output panel and a 400W output panel, at first glance, the panel with the higher output may seem better.
However, if the size of the panels does not fit well on the roof, there may be cases where “20 panels of 350W can be installed” and “15 panels of 400W can be installed,” resulting in 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 one panel is lower, the total output of the roof may be higher!
It is important to consider the total output of the roof rather than the output of a single panel!
*The above is a calculation of total output (kW). The actual power generation (kWh) will vary depending on conditions such as roof orientation, slope, and shading.
How to Choose 2: Compare by Degradation Rate of Solar Panels
Solar panels have a degradation rate, and their output gradually decreases after 10 years and 20 years.
The degree of output reduction after long-term use varies by product. The manufacturer’s output guarantee value is a standard figure for warranty purposes and does not indicate the actual degradation rate or power generation itself.
Choosing solar panels by considering the degradation rate as well as the initial output will help you avoid regrets!
How to Choose 3: Compare by 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!
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 Izumi Ward
We have compiled frequently asked questions from customers considering the installation of solar panels and storage batteries in Izumi Ward. (Tap to open the answers)
How much does it cost to install solar panels and storage batteries in Izumi Ward, Yokohama City?
The cost varies depending on the installation capacity, equipment, and roof condition. In the above construction example (solar panel 4.3kW + storage battery, completed in April 2025), it was 2.2 million yen to 2.3 million yen.
For cost estimates by capacity, please refer to the solar panel installation and storage battery installation pricing page. We will create a layout diagram from the drawings and on-site survey and provide a free estimate!
Are there any subsidies available for solar power and storage battery installation in Izumi Ward?
As of October 6, 2026, the application period for Yokohama City’s YGrEP (15,000 yen/kW for solar power, up to 4kW; 120,000 yen per storage battery) is ongoing (it will end once the budget limit is reached). The Kanagawa Prefecture subsidy (70,000 yen/kW for solar power; 150,000 yen per storage battery) is approaching the application deadline for the second phase of Reiwa 8, and the national DR household storage battery program has ended its public recruitment.
Since the application status may change, please check the subsidy and grant section and consult with us before signing a contract.
Can I apply for subsidies after the construction is completed?
For many programs, procedures are required before construction. Yokohama City’s YGrEP requires a “participation and introduction support application” before installation, and Kanagawa Prefecture’s subsidy requires “construction to start after the grant decision,” so if you install first, you will be ineligible.
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. The fixing method varies by construction method, and in methods that fix hardware to the roofing material or substrate, waterproofing treatment of the fixed parts is essential.
Kakeru Koumuten is a specialist 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 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 after 10 to 20 years, there will be additional costs for removing and reinstalling solar panels. If the remaining lifespan of the roof is short, it may be more cost-effective to renovate with durable roofing materials before installation.
Please consult us on how to proceed with the installation after confirming the condition of the roof through a site survey!
Should I install a storage battery together with the solar panels?
For those who want to use the generated electricity at night or prepare for power outages, simultaneous installation is recommended. Since the selling price of electricity will be 8.3 yen/kWh after the fifth year, it is generally more beneficial to use it at home rather than selling it.
Additionally, Kanagawa Prefecture’s subsidies require the simultaneous introduction of solar panels and storage batteries, and Yokohama City’s YGrEP also has conditions for combinations with storage batteries. You can compare “solar panels only” and “solar panels + storage batteries” through 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, we create a layout diagram from the drawings and site survey, and provide you with the installation capacity and power generation simulation.
Izumi Ward has gently rolling hills and plateaus, with plenty of farmland and greenery, so the shadows from neighboring houses, trees, and elevation differences vary from one house to another. 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 panels 4.3 kW + storage battery), it took about 3 days. The duration may vary if roof work is done simultaneously or depending on the shape of the roof and installation capacity.
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 (less than 10 kW), the selling price from certifications after October 2025 will be 24 yen/kWh for the first 4 years, and 8.3 yen/kWh from the 5th to the 10th year, and the same price will apply for the 2026 fiscal year.
The idea is to recover initial costs quickly in the first 4 years and then focus on self-consumption. Kakeru Koumuten provides a financial simulation that takes into account loan interest rates and electricity costs.
Can you handle maintenance and inspections after installation?
Yes, we can. Kakeru Koumuten sends out annual after-service maintenance notices via DM and visits customers who wish for inspections. We can also clean solar panels using a special brush if the power generation decreases due to dirt.
Since it is difficult to check areas on the roof by yourself, 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. Kakeru Koumuten can remove and reinstall solar panels in-house, so we will handle the process of removing the panels, performing the roof overlay (cover method) or re-roofing, and reinstalling them consistently. The removed panels can be stored in our warehouse.
For information on costs, please see the solar panel removal and water heater removal pricing page.
If you are looking for a solar panel installation company in Izumi Ward, consult Kakeru Koumuten
Our company handles a wide range of exterior renovations, from roofing work to exterior wall work, including solar panels, in Izumi Ward, Yokohama City.
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 positive feedback from numerous customers.
We continue to update our construction achievements every year and will strive to improve quality to satisfy even more customers in the future.
Our company can perform all exterior renovations, not only roof overlay work and re-roofing but also partial roof repairs, exterior painting, and exterior cover methods.
We are also happy to handle small jobs such as partial repairs and rain gutter cleaning!
In urgent cases such as leak repairs, we may be able to provide emergency measures without setting up scaffolding, as long as safety can be ensured, so please consult with 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 the best 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 plans!
We are confident that we will not be outdone by other companies in terms of cost, quality, and planning for exterior work!
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 Izumi Ward, Yokohama City, and Points for Solar Power Work
Izumi Ward, Yokohama City, is located in the southwestern part of the city, with residential areas spreading along the Sotetsu Izumino Line and the Yokohama City Subway Blue Line.
Below are summarized points regarding the terrain and housing situation in Izumi Ward, as well as important considerations when installing solar panels and storage batteries. (Tap to open)
View the characteristics of Izumi Ward, Yokohama City, and points for solar power work
■ The hilly terrain and plateaus require attention to roof shadows and scaffolding planning
The area of Izumi Ward is approximately 23.56 km2, making it the 10th largest in Yokohama City. The introduction page for Yokohama City wards describes it as “a gently rolling hilly area where rivers form terraces, creating variations.” Within the ward, the Izumi River, Akukawa River, and Udagawa River flow, while the Sakai River and Aizawa River flow along the borders.
Even within the same block, the orientation and height of roofs, as well as the shadows cast by neighboring houses, retaining walls, and trees, vary from one house to another. At Kakeru Koumuten, we create layout diagrams based on blueprints and the actual site conditions, and we confirm them through power generation simulations. In areas with elevation differences, our own scaffolding team plans the scaffolding to suit the site.
■ Abundant farmland and greenery, with attention to fallen leaves and dirt
According to Yokohama City materials (as of 2014), Izumi Ward has the largest farmland area among the 18 wards and the highest proportion of urbanization control areas. While it is an area close to farmland and greenery, roofs near trees are prone to fallen leaves and dirt sticking to the panels, which can lead to a decrease in power generation. Additionally, if there are tall trees near the site, attention must also be paid to the shadows cast on the panels. Kakeru Koumuten can also handle solar panel cleaning with specialized brushes and rain gutter cleaning.
■ Check the roof condition before installation in housing complexes and residential areas from the late Showa period
Izumi Ward was established in 1986, and prior to that, large-scale public housing complexes were formed in the Kamiiida area around 1964 to 1971. In 1976, the Sotetsu Izumino Line opened between Futamatagawa Station and Izumino Station, and it was extended to Shonandai Station in 1999. Within the ward, the proportion of first-class low-rise residential areas is 36.5% (according to Yokohama City materials), creating a calm residential area centered on low-rise housing.
For houses that have aged since construction, 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.
■ Yokohama’s annual sunshine hours are approximately 2,018 hours
According to the Meteorological Agency’s average values (1991-2020), Yokohama’s annual sunshine hours are about 2,018 hours. Monthly, August has the most hours, while June during the rainy season has the least.
Power generation varies by season, so conducting annual power generation simulations and selecting battery capacities that align with peak electricity usage times are key points.
■ Consideration for residential area rules
In Izumi Ward, there are building agreements for the Nishigaoka and Okazu districts (not all areas of the ward have the same rules). In regions with stipulations regarding installations on roofs, it is necessary to confirm the details in advance.
Our company is based in Yokohama City and handles many exterior construction and solar projects in Izumi Ward, Yokohama.
We are happy to assist with partial roof repairs such as roof overlay work, roof replacements, and leak repairs, as well as other repairs! Please feel free to consult us about any sudden troubles!
Service Area in Izumi Ward, Yokohama City
Kakeru Koumuten accepts requests throughout Kanagawa Prefecture and Tokyo.
Yokohama City Izumi Ward Area List
Izumi Ward Ikenotani / Izumi Ward Izumigaoka / Izumi Ward Izumichuo North / Izumi Ward Izumichuo South / Izumi Ward Izumimachi / Izumi Ward Okazumachi / Izumi Ward Katsurazaka / Izumi Ward Kamiiida Town / Izumi Ward Shimoida Town / Izumi Ward Shimoizumi / Izumi Ward Shirayuri / Izumi Ward Shinbashicho / Izumi Ward Nakada North / Izumi Ward Nakadamachi / Izumi Ward Nakada West / Izumi Ward Nakada East / Izumi Ward Nakada South / Izumi Ward Nishigaoka / Izumi Ward Yayoidai / Izumi Ward Ryoke / Izumi Ward Ryokuen
・Trust Kakeru Koumuten for exterior wall painting in Izumi Ward, Yokohama!
・Trust Kakeru Koumuten for roof renovations in Izumi Ward, Yokohama!
・Trust Kakeru Koumuten for exterior renovations in Izumi Ward, Yokohama!
・Trust Kakeru Koumuten for leak repairs in Izumi Ward, Yokohama!
・Trust Kakeru Koumuten for waterproofing work in Izumi Ward, Yokohama!
・Kakeru Koumuten Co., Ltd. construction achievements
・Kakeru Koumuten Co., Ltd. aftercare services
・Kakeru Koumuten Co., Ltd. construction menu and price list
・Kakeru Koumuten Co., Ltd. staff blog and announcements
・Explaining the importance of comparative estimates and key points!
・12 major manufacturers of solar power generation! Also introducing features and selection points!
・What are the installation costs for solar power generation? Thoroughly explaining tips to reduce costs!
・What are the best locations for installing solar power generation? Also introducing key points for site selection!
・Here is the introduction for solar power generation estimates!
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contact Kakeru Koumuten Co., Ltd.
Kakeru Koumuten is a young company whose team is, on average, in their late twenties, but our skills are second to none.
Our greatest strength is that we handle scaffolding, roofing and painting entirely in-house. In an industry where these tasks are usually divided among contractors, our complete service simplifies project management and helps keep costs down. Above all, if a problem arises, we respond promptly.
We proudly describe ourselves as the youngest and most helpful renovation company in Kanagawa!
