My house is in NH, 4' to freeze depth...2 story 40x25 ft section of house that was built on cinder blocks...this wing is living room below and bedrooms above. I have since installed 8 posts underneath as footings...four of these are 4x6 pressure treated posts attached to 4ft concrete footings....the four other are 6x6 pt posts on top of four ft concrete footings...there are still 4 cinder block stacks in place from orig construction remaining...question is this...is 8 enough footings or do I need 4 more footings?