Red is a concrete foundation. Black is rotting wood foundation that needs to be replaced.
Foundation issues suck. House has foundation issues. Most of the foundation will need to be replaced. Part of the house currently has a wood foundation which is rotting. There is an addition which has a concrete foundation. (See image above).
I know that the wood foundation can be replaced with a pier and post foundation. They can stabilize the house, dig and pour piers, then use metal posts to brace the house at the right height.
Is a pier and post foundation the only option? Is there a way to do a concrete foundation?
Edit: The image is a top down look at the perimeter of the house. The red part is a ~600 sqft addition. The black part is the main house.
The house is not occupied and there is access to the crawlspace.
My main concern is that I'm not sure a concrete foundation can be built underneath the house. Since it has the addition which a concrete foundation, the house cannot be lifted. The weight bearing concrete would have to be built upto the level of the house...which I'm not sure is possible.
A basement would be amazing.
I have seen time-laps videos on Youtube of a company that retrofits houses that have crawl spaces with full basements. It is pretty amazing to watch them work. They hand dig out sections at a time and pour footings and supporting walls, they then do a final pouring of the floor. They do this without lifting the house.