Roof Overlay (Cover Method) for Lower Roofs | Yamato City | Slate to Alma Roof Overlay Completed!

BEFORE

AFTER

Hello!
We are Kakeru Koumuten Co., Ltd., a specialist 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 Yamato City, Kanagawa Prefecture.
The work this time involves the roof overlay (cover method) by Aruma!

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

Roof Overlay Construction Procedure

1. Dismantling Existing Ridge and Snow Stops

We will dismantle unnecessary parts (ridge flashing) for the overlay method! The lifespan of wooden purlins is about 10 to 15 years. Exceeding the lifespan can lead to corrosion and discoloration, resulting in the ridge flashing coming loose or being blown away.

2. Installing Roofing (Waterproof Sheet)

The roofing used is Jouyu Pulp Industry/Sunlight G!
It is made of modified asphalt roofing, which is said to have double the lifespan of regular asphalt roofing.
As a primary waterproofing measure, if the roofing is properly installed, there will be no leaks! We will ensure it is securely attached to prevent it from blowing away.

4. Fabrication of Accessories (Curly Patterns and Eaves)

Before the main roofing work, we will process and install components such as eaves and decorative elements!
The materials used are made of galvalume steel.

4. Main Construction (Nichiwa/Alma)

After processing the components, we will install the Alma main body up to the ridge! We will also securely apply single cement during the installation.
Once we have installed up to the ridge, we will set up a material called a “nuki” which is necessary for fixing the ridge flashing. There are types of nuki made from cedar and resin, and this time we used a resin type!
The resin type is expected to have twice the durability compared to the cedar type!

5. Ridge Flashing Processing & Sealing at Various Locations

Next, we will process and install the ridge flashing. We will securely apply sealing on the inside of the joints. At the wall edge, we will process and install a component called a rain guard flashing.
The nails and screws used for fixing are made of stainless steel, which is resistant to rust!

6. Cleaning

We will clean up the debris that has fallen onto the balcony and rain gutters. We will thoroughly remove items like nails and metal scraps that could lead to injuries.

About Roofing Materials

The roofing material used is Nichiha’s Aruma.
Aruma comes with a 10-year manufacturer warranty.
Since it uses natural stone that is baked onto the surface, it is a roofing material that does not require painting, which helps to reduce maintenance costs!
The use of fine natural stones on the surface means you won’t be troubled by the sound of rain.

It excels in finish, durability, sound insulation, and wind resistance, and is lightweight compared to other roofing materials, which reduces the sway during earthquakes, making it effective for earthquake resistance.
In the recent overlay (cover) work done, the roof becomes double-layered, which increases the weight, but Aruma is a lightweight roofing material, making it suitable for overlay (cover) work.

Colors

■ Black AR

■ Gray AR

■ Green AR

■ Brown AR

■ Camel AR

This time, the roof work with Green AR turned out exceptionally well!
The customer was very satisfied, and I was also very happy!
Thank you very much!

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 as it is 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 “layered roofing.”

Advantages of the Overlay Method

Since a “new roof” is placed over the “current roof,” almost no demolition work is required, meaning very little waste is generated.
This is the main feature, leading to various advantages.

The only parts that require demolition and waste disposal are 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 more details, please refer to the Ministry of Health, Labour and Welfare website).
Some building materials used in structures built before 2004 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 with asbestos-containing materials?” but 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 with us.

Additionally, the construction can be completed in a shorter period compared to painting or complete roof 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 set up, there may be inconveniences such as difficulty entering and exiting or not being able to open windows. Being able to return to 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 do. We are very grateful that we are continuously able to carry out roof overlay method projects without interruption.

Summary

Roof Material	Nichiha/Alma
Manufacturer Warranty	10 years
Expected Durability	About 20 years
Color Used This Time	Green AR

Leave Your Roof Renovation in Yamato City to Kakeru Koumuten!

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

As an exterior renovation company based in Aoba-ku, Yokohama, we have handled many roof renovations throughout Kanagawa Prefecture and have a deep understanding of the needs of local customers.

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

“I want to keep costs as low as possible.”

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

We provide optimal solutions for specific requests like these.

Conclusion

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

Kakeru Koumuten Co., Ltd. is a remodeling company strong in exterior renovations, and we carry out everything from temporary scaffolding work to roof work and exterior painting completely in-house.
When it comes to exterior renovation work, we are confident that we do not fall short compared to other companies in terms of “cost, quality, and efficiency”!

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

We want you to think, “I’m glad I asked them!” Therefore, we take every request we receive seriously.

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

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

Helpful information about exterior renovations can be found here!

We welcome inquiries via LINE as well◎

LINE

We are also updating our Instagram regularly◎ Please follow us◎

Instagram