For inquiries about quasi-non-combustible certification by applying it [post-installation]

There are many inquiries from the design office. The contents are as follows.

“I want to use wood in the interior of the complex, but will painting make it a non-combustible product?”

This is not a certified non-combustible product from the answer.
I want to do something in the mountains, but at this point the law is so built and there is nothing I can do about it.
In the case of construction, the Building Standards Law stipulates that construction of materials that exceed quasi-incombustibility certification is required at specified locations. For example, if you want to finish the interior of a restaurant with wood paneling, in most cases you are subject to interior restrictions under the Building Standards Law.
In such a case, the design office will contact you.

The answer is NG, but why NG in the first place? There aren’t many sites answering that, so I’d like to explain.

First of all, there is the Building Standards Law, which states that certain buildings must be built so that they do not burn.
Correspondingly, there is a rule that if you use it, you should use non-flammable materials or equivalent materials.
And non-burnable materials are already specified, such as concrete and glass.
However, there are various types of building materials, so there is a rule that other materials should be treated as non-burnable if they demonstrate certain performance. That is the flame retardant / quasi-non-combustible / non-combustible material certified by the Minister of Land, Infrastructure and Transport
Therefore, only materials that pass this certification standard can be used.

And this certification test has various standards, and it must prove that it does not burn even in a fire.
In addition, since there is a problem if there is variation depending on the product, a review will be made on the manufacturing method etc. After that, it is proved that everything is OK at the designated testing institute, and when the Minister of Land, Infrastructure, Transport and Tourism receives a notice of approval, it is a variety of certified products.

Now consider wood.
The basic idea is the same for wood. Wood is a material normally recognized as combustible. Therefore, use to the designated place is not permitted as it is.

If you want to use wood for interior decoration etc., it means that only non-combustible wood manufactured by the company that obtained the certification number by the certified method is allowed.
This has already passed the test and the manufacturing process has been certified, so a certification number has been assigned to wood that is manufactured at the factory that meets the conditions.

However, what many design firms want is to paint on the siding slabs constructed at the site later and give the material a certified number as a quasi-noncombustible product. However, certification cannot be obtained unless the above procedures are followed, and materials constructed on site have not been tested in the first place, so they will not be recognized as certified products.
According to our Ministry of Land, Infrastructure, Transport and Tourism, we have received a response saying, “It is unlikely that there is a product that can be certified for on-site application.”
By the way, it takes several years to get certified under the current system. The certification system for incombustible wood is so complicated.

Although we are researching non-combustible wood, our chemical-coated materials can easily burn when tested at certified levels. Although there is a flame retardant effect even when applied, non-combustible wood is required to have even higher performance, so the performance will not reach unless it is treated by immersion instead of application.

The image below is a comparison combustion experiment with soufa applied. Although this alone can be said to have a sufficient flame retardant effect, it is not possible to pass the building material certification test with this degree. It can be said that the performance required in the certification test is so high.

There are many paint manufacturers among the companies that contact us.
These companies are trying to solve the above problems, and some companies seem to be exploring the possibility of obtaining accreditation by on-site application. However, building a current certification system is a very difficult challenge.

At present, there are various types of non-combustible plywood using wood board, so using them to think about design may broaden the scope.