The chimney is for the furnace. I think he is going to demo that back little room and rebuild it afterwards. The furnace and stuff in there is sitting on a concrete slab.
The reason for needing to raise it is because its on piers. When inside there is the dining room downstair and bedroom upstairs that you can see the floor/walls have sagged down. Dave is under the impression, and I hope he is right, that by lifting the house and putting a real foundation under it, will mostly level out the floor/walls again.
Is there another way ?
And yes, the barn thing is going to be his... all his.