“Use the lumber in the same direction as it grows”
It is a famous oral tradition of a palace carpenter that it is important to identify and utilize the habits of each tree depending on where it grows.
The tree that grew on the south side of the mountain is on the south side of the temple. The tree on the north side is on the north side of the temple. Bring trees that have been trained in the sun for many years to the sun. The trees on the south side are hard because of the sun. So make it a pillar. South and east trees face the shaft. The basic idea is that the trees that grow in the west are calm and suitable for construction materials.
Architecture up to Asuka, Hakuho, and Tenpyo honestly follows this rule. Asuka architecture does not have to be dismantled until about 1,300 years. It grows naturally and is used in the same orientation. It is generally accepted that buildings after Muromachi need to be dismantled and repaired in 500 or 600 years.
Horyuji Temple is all cypress. In the Nihon Shoki, it is written that hinoki should be used as a material to make Mizumiya, that is, a palace, and Sugi and camphor trees should be used as boats. The material is dense, sticky, resistant to moisture, and free from insect damage. In general, cypress is the most durable, and cypress over 1000 years old is said to be the best.