The reason why many companies do not adopt seismic resistance grade 3 is simply because they do not have staff in-house who can calculate allowable stress levels.

November 6st
The reason why many companies do not adopt seismic resistance grade 3 is simply because they do not have staff in-house who can calculate allowable stress levels.
Because I think it would cost about 150,000 yen if I outsource it. Because it takes time to outsource.
I think all of this is just the logic of the companies.
So I decided to look into the monetary value of building a house with seismic resistance ratings of 1 or 2, and then covering it with earthquake insurance in the event of a major earthquake.
http://www.ms-ins.com/personal/kasai/jishin/example.html…
With the building valued at 25 million yen and the furniture and goods valued at 2 million yen, the annual insurance premium would be approximately 40,000 yen, or 400,000 yen over 10 years, or 1.2 million yen over the typical loan period of 30 years.
The base earthquake resistance rating varies from company to company, but no matter which company
I think you can upgrade your home to earthquake resistance class 3 with just 400,000 yen. And with 1.2 million yen, you can definitely do it with ease.
This is what is known as a "market distortion" that is rarely seen outside the housing industry.
Although it would be absolutely more advantageous to build to earthquake resistance level 3, almost no one actually does this.
In the world of investing, if there were such a market distortion, arbitrage transactions would be carried out in less than 0.01 seconds and the distortion would be eliminated.
Dear housing professionals, why don't you stop selling houses with low earthquake resistance that make people drive their cars without optional insurance just for your own convenience?