Depends on the country. It's a reinforced concrete structure( including floors) where I live and double brick walls with insulation between them here. We have l

Depends on the country. It's a reinforced concrete structure( including floors) where I live and double brick walls with insulation between them here. We have lots of sand so concrete is relatively cheap. I have literally never seen a single house made out of wood here and I have been to a lot of construction sites.