Tama-ku, Kawasaki City | We performed a roof overlay (cover method) from Zalfugrassa to Hiranbee 220!

BEFORE

AFTER

Hello!
We are Kakeru Koumuten Co., Ltd., specialists in roofing, exterior wall painting, and exterior renovations located in Aoba-ku, Yokohama, Kanagawa Prefecture!
This is a case study of an exterior renovation project in Tama-ku, Kawasaki City.
The work this time involves the roof overlay (cover method) using Hiranbi 220!

On this page, we will explain the actual results of the work carried out by Kakeru Koumuten!

The existing roofing material was Zarufugurassa, which cannot be painted, so we proposed a roof overlay project!

Thank you very much for choosing Kakeru Koumuten Co., Ltd. from among many contractors.

Construction Data for Tama-ku, Kawasaki City

Roof Replacement Construction Photos

1. Removal of Ridge and Snow Stops

We will only dismantle and remove the existing ridge and snow stops!

2. Installing Roofing (Waterproof Sheet)

We will lay the roofing sheet (waterproof sheet) over the underlayment! The roofing used is Jouyu Pulp Industry/Sunlight G!
It is made of modified asphalt roofing material, which is said to have double the durability of regular asphalt roofing.
With the role of primary waterproofing, if the roofing is solid, there will be no leaks!
We will ensure it is securely attached to prevent it from blowing away.

3. Fabrication of Accessories (Curlicue and Eaves)

Before the main roofing work, we will process and install components such as eaves and decorative metalwork! If there are skylights, we will also process the metalwork around the skylights!
The materials used for the components are made of galvalume steel.

4. Main Construction (Inagaki Shouji / Hiranbee)

After processing the components, we will install the Hiranbee main roofing material up to the ridge! Snow guards will also be installed while laying the roofing material!
Once we reach the ridge, we will install the necessary materials for securing the ridge board, known as the “kanban.” There are types of kanban made from cedar and resin, and this time we used the resin type!
The resin type is expected to have twice the durability compared to the cedar type!

5. Ridge Cap Processing & Sealing

Next, we will process and install the ridge cap. We will apply sealing thoroughly on the inside of the joints. At the wall edges, we will process and install components called rain guard metalwork.
The nails and screws used for securing are made of stainless steel, which is resistant to rust!

6. Cleaning

We will clean up the debris that has fallen on the balcony and rain gutters. We will thoroughly remove items like nails and metal scraps that could cause injuries. We will also wipe away any footprints left on the roof to ensure it looks clean!

About Roofing Materials

The roofing material used is Hiranbi 220 from Inagaki Shouji.
Hiranbi 220 comes with a manufacturer warranty of 15 years for the coating and 25 years for perforation.
For re-roofing and roof overlay, we also provide a 10-year construction warranty!
If there are any leaks within 10 years, we will make repairs free of charge.
Made of Galvalume steel, it is resistant to rust.
The shaped panels are treated with iris folding and wave processing to prevent distortion and enhance strength, as well as improve rainwater drainage and aesthetic effects.

Additionally, it excels in finish, durability, sound insulation, and wind resistance, and is lighter compared to other roofing materials, which reduces the sway during earthquakes, making it a good earthquake countermeasure.
In this overlay (cover) construction, the roof becomes double-layered, which increases the weight; however, Hiranbi is a lightweight roofing material, making it suitable for overlay (cover) construction.

Color

Extreme – MAX Type
■ Gray Silver

■ Silver Black

■ Sepia

■ Moss Green

■ Bamboo Green

■ Midnight Blue

■ Jet Black

■ Dark Brown

■ Bright Red

General Type
■ Steel Black

■Marron Brown

■J Silver

You can choose from these options!

This time, the cover work with Silver Black turned out exceptionally well!
Thank you for your request!!

Please check out other roofing work examples from here!

What is the Roof Overlay (Cover Method)?

The roof overlay method involves leaving the current roof almost intact and placing a new roof on top of it, effectively covering it.
Literally, it is a method of covering a roof with another roof. Therefore, the roof becomes double-layered. Since the roof is layered, it is also referred to as “overlapping roofing.”

Advantages of the Overlay Method

Since a “new roof” is placed over the “current roof,” demolition work is almost unnecessary, meaning that very little waste is generated.
This is the biggest feature and leads to various advantages.

The only part that requires demolition and waste disposal is the ridge cap, making it more cost-effective compared to complete roof replacement.
In 2004, regulations regarding the concentration of asbestos in raw materials were changed (for details, please refer to the Ministry of Health, Labour and Welfare website).
Building materials used in structures constructed before 2004 may contain asbestos. Asbestos-containing materials are difficult to demolish due to their high environmental impact, and the costs for demolition and waste disposal are also high. The overlay method, which generates almost no waste, is ideal for such roofs.

Some may wonder, “Is it safe to live in a building that uses asbestos-containing materials?” Rest assured. As long as there is no destruction or crushing, it will not disperse into the air.
If you are unsure about the type of roof on your home, please feel free to consult us.

Additionally, it can be completed in a shorter time frame compared to painting or complete replacement. A shorter construction period means lower labor costs, which in turn makes the overall cost cheaper.
The psychological anxiety of having to live in an unusual environment is also reduced.
When scaffolding is erected, you may experience inconveniences such as difficulty entering and exiting or being unable to open windows. Being able to return to your normal life in a short period is a significant advantage.

Our company specializes in roofing work, and the roof overlay method is the most frequently performed type of work we undertake. We are very grateful that we have been continuously engaged in roof overlay projects without interruption.

The Necessity of Roof Construction (Roof Repair) and Maintenance Schedule

◇ Necessity and Purpose of Roof Construction and Repair

・Necessity and Purpose of Roof Construction

The roof is directly exposed to damage from rain, wind, and ultraviolet rays, and problems such as cracks and leaks become apparent over time. By carrying out roof construction, we can enhance the durability of the building and maintain a comfortable living space. Additionally, improvements in energy efficiency can be expected. For example, using highly insulating roofing materials can lead to reductions in heating and cooling costs.

In terms of long-term cost performance, roof construction can be considered an important investment.

・Schedule for Roof Construction (Roof Repair)

Depending on the type of roofing material and the local climate, it is generally recommended that roof construction (roof repair) be carried out every 10 to 15 years. After that, inspections should be conducted approximately every 5 years, and repairs or painting should be performed as necessary. Regular maintenance can help detect small deterioration or damage early, reducing the risk of large-scale construction or repairs.

However, this is merely a guideline, and it can vary based on the material of the roof and environmental conditions such as high humidity, strong winds, and snowfall. In harsh weather conditions, more frequent checks may be necessary. Additionally, since roof construction (roof repair) involves working at heights, it is advisable to hire a professional contractor.

Post-Construction Maintenance

◇ Importance of Post-Construction Maintenance

Maintenance after exterior painting and roof repair is a crucial factor in extending the lifespan of the home. Neglecting maintenance can lead to rapid deterioration of newly painted exteriors and repaired roofs, resulting in the risk of incurring high costs. The exterior walls and roof of a building are constantly exposed to harsh natural environments such as rain, wind, ultraviolet rays, and temperature changes. Regular maintenance can minimize damage and help maintain the home’s aesthetics and comfort. Furthermore, it can help avoid large-scale repair work and the associated significant expenses.

◇ Maintenance Methods and Frequency

One effective method for post-construction maintenance is inspections by professional contractors. This allows for early detection and repair of even minor damage. The recommended frequency for maintenance is generally exterior painting every 5 years and roof repair every 3 years. This is just a guideline and may vary based on local climate conditions and the structure of the home.

Leave Your Roof Renovation in Tama-ku, Kawasaki to Kakeru Koumuten!

Our company has extensive experience in roof renovations in Tama-ku, Kawasaki.
We are happy to assist with partial roofing work such as roof overlay, roof replacement, and leak repairs.
If you have any questions or concerns, such as “I just want to know the estimate for the roof work” or “I want to know about roofing materials,” please feel free to contact us!

Community-Focused Service

As an exterior renovation company based in Aoba-ku, Yokohama, we have handled many roof renovations in nearby Tama-ku, Kawasaki, and we deeply understand the needs of our local customers.

“I want it to last a long time with just one renovation”

“I want to keep costs down as much as possible”

“I want to improve insulation performance because the indoors are hot”

We provide optimal solutions for specific requests like these.

Long-Term Reliability

All the roofing materials we use are reliable products that come with long-term warranties. For example, the Hiranbi 220 from Inagaki Shouji, which we used this time, has a manufacturer warranty of 15 years for the coating and 25 years for perforation, allowing you to use it with peace of mind for a long time after just one renovation.
Hiranbi is a lightweight roofing material that excels in durability and cost performance, but we also offer roofing materials with even higher durability and better insulation properties.

Summary

Estimates and inspections are, of course, free! If you have any concerns regarding roofs, rain gutters, exterior walls, or exterior structures, please consult Kakeru Koumuten Co., Ltd. in Aoba-ku, Yokohama!

Kakeru Koumuten is a remodeling company strong in exterior renovations, and we carry out all work from temporary scaffolding to roofing and exterior wall painting completely in-house.
Regarding exterior renovation work, we are confident that we will not be outdone by other companies in terms of “cost, quality, and efficiency”!

We are confident in our exterior renovations, so we welcome competitive estimates!
We also provide comprehensive construction guarantees and aftercare maintenance, and we have received positive feedback for our appropriate proposals that match cost performance and our customers’ future life plans!

“I’m glad I asked them!” We take every request seriously to ensure you feel this way.

We also have information on roofing costs and pricing plans for roof overlay (cover method), so please take a look if you are interested!

We look forward to your inquiries. Thank you very much.

Useful information about exterior renovations can be found here!

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