i am trying to raise the main beam in my three decker in worcester. it currently has four wood posts made from tree trunks app. 8 inch diameter holding it. they all sit on some concrete, although i don't know how deep. i need to raise one end( including two posts) about one inch. i want to replace the wood posts with 4 inch filled lally columns, but i am wondering about the distance between the new posts and do the new 4 inch support the same weight as the old wood posts?