Construction example

Yamato City, Kanagawa Prefecture | We performed a roof overlay (cover method) on the lower roof using Ridgeway!

BEFORE

AFTER

Hello!
I am Yamanaka from Kakeru Koumuten Co., Ltd., a specialist in roofing, exterior painting, and exterior renovations located in Aoba-ku, Yokohama, Kanagawa Prefecture!
This is a case study of exterior renovations in Yamato City, Kanagawa Prefecture.

On this page, I will explain the actual achievements we have accomplished at Kakeru Koumuten!

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

 

 

Roof Overlay (Cover Method) Construction Steps

1. Dismantling Existing Ridge Flashing


We will dismantle the unnecessary existing ridge flashing for the cover method!

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 durability 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.

3.Accessory Processing (Karukusa & Keraba)

Before the main roof construction, we will process accessories such as keraba and karukusa sheet metal!
The materials used for the accessories will be galvalume steel.

4.Main Construction (Asahi Fiberglass/Ridgeway)

After processing the accessories, we will install the Ridgeway main roofing up to the wall edge! We will apply single cement at the overlapping areas during the installation.
Once the roofing is completed, we will install the necessary materials for fixing the ridge board, known as the “kanban.” There are two types of ridge boards: cedar and resin, and this time we used the resin type!
The resin type is expected to have three times the durability compared to the cedar type!

5.Ridge Board & Sealing at Various Locations

We will process and install the ridge board. We will firmly apply sealing on the inside of the joints. At the wall edge, we will process and install a component called rain stop sheet metal.
The nails and screws used for fixing will be 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. The balcony will be restored to its original condition upon completion of the work!

About the Roofing Material (Ridgeway)

The roofing material used is Ridgeway from Asahi Fiberglass.
Ridgeway 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 reduce maintenance costs!
The use of fine natural stones on the surface means you won’t be troubled by rain noise.
Additionally, it is a lightweight roofing material, making it strong against earthquakes and providing seismic resistance.

* After installation, the surface decorative stones may fall off for about a week, but there is no issue with quality.

Colors

■ Dual Black
Ridgeway Black

■ Harvard Slate
Ridgeway Harvard Slate

■ Vintage Green
Ridgeway Green

■ Dual Brown
Ridgeway

■ Earthtone Cedar

Ridgeway Earthtone Cedar

This time, we completed a roofing project with a vintage green finish, and it turned out exceptionally well!
The customer was very satisfied, and I was also very happy!
Thank you very much!

Please check out our other roofing project achievements 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 laid over, 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 material is generated.
This is the biggest feature and leads to various advantages.

The only parts that require demolition and waste disposal are the ridge cap, so compared to complete roof replacement, the cost is lower.
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).
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?” 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 us.

Additionally, it can be completed in a shorter time frame compared to painting or full roof replacement. A shorter construction period means lower labor costs, which in turn makes the overall cost lower.
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 in entering and exiting or opening 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 undertake. We are very grateful that we consistently have ongoing projects for roof overlay work.

Roof Material

Asahi Fiberglass/Ridgeway

Fiberglass Ridgeway
Manufacturer Warranty 10 years
Expected Durability 25 to 30 years
Color Used This Time

Vintage Green

Ridgeway Green

Leave Your Roof Renovation in Yamato City, Kanagawa to Kakeru Koumuten Co., Ltd.!

Our company has extensive experience in roof renovations in Yamato City.
We are happy to assist with partial roof repairs such as roof overlay work, roof replacement, and leak repairs.
If you have any questions or concerns like “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 long 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 issues with 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 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 offer comprehensive construction guarantees and aftercare maintenance, and we have received positive feedback for our cost performance and appropriate proposals that align with our customers’ future life plans!

We want you to think, “I’m glad I asked!” Therefore, we take every request we receive seriously and work diligently on it.

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!

 

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For roofing, guttering, and exterior work and repairs in Kanagawa, contact Kakerukoumuten Co., Ltd..

AAA is a young company with an average age in the early 20s, but our technology is second to none.

One of our greatest strengths is that we can do all of our own scaffolding, roofing, and painting work. In this industry, where work is generally divided, we are able to provide a complete set of services, which saves time and effort in management and reduces costs. Above all, if there is any trouble, we will come to you right away!

We can confidently declare this. We are the youngest and most friendly renovator in Kanagawa!