Contact your lender and tell them what is happening. You may find that your lender might be willing to do something here, remember they have a vested interest here too. Did the appraiser say what the home would be worth if the home were corrected? Did you buy the home as a foreclosure or did you deal with a homeowner? Were Realtors involved in the sale? Talk to your neighbors and find out if the previous owner or listing realtor or even your realtor knew about the defect? Realtors and owners are to disclose ALL known defects. How long after the sale has it been since you discovered the defect? You'll have to do some investigation work here. By the way, Did you waive inspections? If you had an inspection, was there any note about this on the inspectors report? You have some work to do here, but if you feel unsafe in the home, go with your gut feeling, start calling people NOW.