Expert: Ted Barnhill (Principal, Design45 LLC) - 1/5/2008

Question
hi Ted, we baught a wartime home a few years ago and before we bought it we had a home inspection done. My question to you is about our floor support(joists). Our house is 24'x24', the centre support beam is 2 2x8's on top of 3 2x8's, supported by 3 jack posts. from the centre beam to the outside edges there are 2 2x8's every 4', and between the 2 2x8's there are 2x4's every 16". The house has sagged in the middle. Is this safe?

Answer
Robert,

Has the home sagged since you have owned it?

Your joists and beams sound roughly OK (but a visual inspection might prove otherwise).  It sounds like the problem is likely to be your center columns or footings.  Some "jack posts" (adjustable steel columns) are acceptable as permanent columns if properly installed, others are only meant to be temporary.  Columns must bear on a concrete pad to distribute the load; these would ordinarily be at least 24"x24"x12" and poured on undisturbed or properly compacted soil.

It may or may not be unsafe, or getting worse over time.  I recommend that you have a local contractor (or several) provide estimates to level your home.

Good luck, and feel free to follow up with additional questions. -Ted