What is an Asphalt Shingle? We will introduce useful information such as features, lifespan, advantages, and disadvantages!

Hello everyone! This is Kakeru Koumuten Co., Ltd.!

Here we will introduce ‘Asphalt Shingle’!

We will provide a detailed introduction to asphalt shingles, which many people surprisingly don’t know much about!

About Asphalt Shingles

There are various types of roofing materials, such as tiles and metal roofs. One of those types is asphalt shingles, commonly referred to as “shingles.”

Asphalt shingles originated in the United States and have an impressive 100-year history as a roofing material!

Features of Asphalt Shingles

Both glass fiber and asphalt, the raw materials of asphalt shingles, are excellent in waterproofing, making them the ideal roofing material for those seeking a roof resistant to leaks!

With various colors depending on the stone granules, it is a roofing material that suits both Western-style homes and calm Japanese-style homes.

The biggest feature of asphalt shingles is

・high design quality

・Lightweight and highly earthquake-resistant

・Easy to process

For example, we can accommodate homes that want a stylish appearance or those with complex roof shapes that are different from others!

Service Life and Types of Asphalt Shingles

Although there are various types of asphalt shingles depending on the manufacturer, it is said that the service life is 20 to 30 years.

We have compiled a list of asphalt shingle manufacturers that we have experience working with!

Asahi Fiberglass【Ridgeway】

The most frequently installed brand by our company is Asahi Fiberglass/Ridgeway, with a service life of 25 to 30 years.

Ridgeway comes with a 10-year manufacturer warranty.

It has also proven its durability by not experiencing peeling during strong wind tests (46m/s), which is one of the disadvantages of asphalt shingles that will be introduced later. It can be used in areas that frequently experience strong winds and typhoons.

Nichiha Corporation【Alma】

The biggest feature of Alma is that it uses natural stone with a ceramic coating, which allows for high durability.

Another feature is its affordability. Due to its low price, the manufacturer recommends replacement or roof overlay every 10 to 20 years.

This Alma also comes with a 10-year manufacturer warranty.

What are the Advantages and Disadvantages of Asphalt Shingles?

If you’re considering switching to asphalt shingles but are unsure, or if you’ve tried them but found they weren’t what you expected, Kakeru Koumuten will thoroughly introduce the advantages and disadvantages to help you make an informed decision!

Advantages of Asphalt Shingles

Excellent waterproofing

Asphalt shingles are highly water-resistant roofing materials. Therefore, there is no need to worry about leaks. The raw materials used, glass fiber and asphalt, provide high waterproofing, and since the roofing materials are fixed with adhesive, there are no holes made by nails in the roof, making them excellent in waterproofing!

Lightweight and Easy to Work With

The roofing material itself is lightweight, so there is no concern about being crushed by disasters such as earthquakes.

Ease of processing is also one of the advantages! While other roofing materials generally only accommodate straight or sloped roofs, asphalt shingles can be used on curved roofs as well.

No Chipping, Cracking, or Rust

Asphalt shingles are more flexible than other roofing materials, so they do not experience cracks typical of tile roofs, nor do they rust like metal materials!

Cost-Effective

Asphalt shingles are cheaper compared to other roofing materials. Since they are imported, prices have drastically increased recently, leading to a decrease in usage compared to before. (As of October 2022) Nevertheless, they still offer high cost performance as roofing materials.

In that regard, they are a reliable roofing material.

Disadvantages of Asphalt Shingles

Impact of Strong Winds

Asphalt shingles are thin sheets of about 6mm, which means they are more prone to being lifted or peeled off by the wind compared to other roofing materials. Additionally, the surface has stone granules that may fall off due to strong winds, and if left unattended for a long time, this can lead to visual deterioration and accelerated aging. They can only withstand wind speeds of 42 to 46 m, so installation in windy areas is not recommended.

Regular Maintenance

This is not limited to asphalt shingles, but all roofing materials require regular maintenance. Since asphalt shingles are vulnerable to strong winds, we recommend regular maintenance to check for any peeling!

Surface Granules May Fall Off After Installation

After installation, granules will inevitably fall off for about a week. After a certain amount has fallen, they will stop coming off, but it can be concerning.
Rest assured, as it is stated in the manufacturer’s catalog that this is not a quality issue.

Fewer Contractors Available

While the number of contractors has been increasing recently, previously, the usage rate of asphalt shingles in Japan was around 5%. There are fewer contractors compared to tile or metal roofs.

Our company handles asphalt shingles!

We will introduce some case studies below!

Roof Overlay Construction Procedure

This construction is a case study from the home of Mr. S located in Yokohama City, Kanagawa Prefecture.

The roofing material used is Ridgeway! We performed a roof overlay construction using Ridgeway!

BEFORE

AFTER

1. Dismantling of Existing Roof Ridge Flashing

We will dismantle the unnecessary existing roofing materials (ridge flashing, snow guards) for the cover method! The existing purlins in the photo are made of wood. 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 Nisshin Kogyo/Kappa 23!
It is made of modified asphalt roofing, which is said to have double the lifespan of regular asphalt roofing.
With the roofing serving as the first line of waterproofing, if it is installed properly, there will be no leaks!
We will ensure it is firmly attached to prevent it from blowing away.

3. Fabricating Accessories (Karakusa, Keraba, Valley)

Before the main roof work, we will fabricate and install accessories such as keraba and karakusa flashing!
The materials used for the accessories are galvalume steel.

4. Main Construction (Asahi Fiberglass/Ridgeway)

After processing the accessories, we will install the Ridgeway main body up to the ridge! We will apply single cement at the overlapping areas during the construction.
Once we have installed it up to the ridge, we will set up a material called a “kanban” which is necessary to secure the ridge flashing. 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 three times the durability compared to the cedar type!

5. Processing of ridge flashing and sealing at various locations

We will process and install the ridge flashing. We will firmly 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 securing 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 clean up nails and metal scraps to prevent injuries.

Roof replacement construction procedure

This construction is a case study at the residence of Mr. Y located in Miyamae-ku, Kawasaki City, Kanagawa Prefecture! The asphalt shingle roofing material used is Nichiha Corporation’s Alma!

This is a roof replacement from tile roofing to Alma!

BEFORE

AFTER

1. Dismantling Existing Roofing Materials

We will dismantle the existing roofing materials (tiles)! The dismantled roofing materials are waste products from Sekisui/Tiles U! Some may contain asbestos, but the materials we are dismantling this time do not contain asbestos! We will introduce how to distinguish them in the future! Tiles U without asbestos are fragile and prone to leaks.

2. Installing New Sheathing

After dismantling the existing roofing materials, we will process and install new field boards to fit the dimensions!

3. Roofing Installation (Waterproof Sheet)

The roofing used is Tajima Roofing / Tadi Self!
It is made of a delayed adhesive modified asphalt roofing material, which is said to havetwice the durability of regular asphalt roofing.
With the roofing serving as the primary waterproofing, if it is installed properly, there will be no leaks!
We will secure it firmly to prevent it from blowing away.

4. Custom Fabrication (Kera, Karakusa, Valley)

Before the main roofing work, we will fabricate and install custom pieces such as kera, karakusa, and valley metal!
The materials used for these custom pieces are Galvalume Steel.

5. Main Construction (Nichihwa / Alma)

After processing the components, we will install the Alma main body up to the ridge! We will also firmly apply single cement during the construction.
Once we have installed it up to the ridge, we will set up the necessary materials to fix the ridge board, known as the kanban. There are types of kanban made from cedar and resin, and this time we used cedar due to budget considerations!

6. Processing of Ridge Metal and Sealing at Various Locations

We will process and install the ridge metal and ventilation ridge. We will firmly apply sealing on the inside of the joints.
At the wall edge, we will process and install a component called the rain guard metal.
We will use stainless steel nails and screws that are resistant to rust for fixing!

7. Cleaning

We will clean up the debris that has fallen onto the balcony and rain gutters. We will thoroughly carry this out as nails and metal fragments can lead to injuries.

Q&A about Asphalt Shingles

Leave your roofing work to Kakeru Koumuten Co., Ltd.!

Asphalt shingles are gaining popularity as a roofing material due to their rich color variations and stylish appearance!

While they are relatively inexpensive and highly waterproof, there is a risk of leaks if the shingles come off due to strong winds. Therefore, regular maintenance is necessary.

Let’s choose the best roofing material after comparing the various advantages and disadvantages!

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.!

We carry out everything from temporary scaffolding work to roofing and exterior painting completely in-house. We are confident that our costs, quality, and organization for exterior work are unmatched compared to other companies!
We welcome competitive estimates with confidence!
You’ll be glad you chose us! We take every request seriously to ensure you feel that way.

Helpful information about exterior renovations can be found here!

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