1780 colonial post and beam advice
I am looking for some advice on repairing a 1780 center chimney colonial. I have just had a cement foundation replace a collapsing stone foundation on one half the width of the house. It was previously a dirt crawl space. The other half half the house has an old stone foundation extending about 7 feet into the ground with an interior concrete about 2 feet high retaining wall(that almost looked like a footing but wasn't)and conrete floor. The house sills on that new half are resting on jacks and blocks until the whole house can be leveled. These sills are in good shape. We jacked and supported the house ourselves.
The house has post and beam construction. The problem is on the other half the house. We excavated for footing drains all the way around the permiter of the house. The stone foundation this side looks to be in very poor repair as well and we will need to replace the foundation as well due to severe water problems. This is where the major problems is. The sills appear to be rotted in large sections most notably in a corner where a post which helps supports the 2nd floor. How does one support the vertical post and replace the sill? The current sills appears to be about 8"by 8". I am on a limited budget for hiring contractors and have already had a structural engineer to look at it but thus far no plans and is charging a lot.