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Regulations for load-bearing walls

​Calculation standards for load-bearing walls

​ This book, called the Gray Book, is the standard for calculating allowable stress for wooden structures.


​ The examination body conducts examinations based on this book. If your application does not match the content of this book, the screening agency may not approve your application. If the examination body does not give an OK, it means that the construction cannot be completed.

​ Let's take a look at the regulations for load-bearing walls. First, please take a look at the markings on this page.

​ To make it easier to understand, it is as follows.


- Load-bearing walls with braces should have a column pitch of 90 cm or more, and the floor height should be 315 cm or less.

・For load-bearing walls covered with plywood, etc., the column pitch should be 60 cm or more, and the floor height should be 300 cm or less.

​ Therefore, if you use a 60cm wide load-bearing wall in a plan where it is difficult to install a load-bearing wall, please be careful as the floor height is restricted to 300cm. In addition, the specification regulations of the standard law require the wall magnification to be up to 5.0, but when calculating the allowable stress level, it is possible to increase the yield strength up to 7.0 times.


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