I have about an 8 inch porch slab that appears to be supported by the house foundation on three corners. The northwest corner stands alone with a pillers supporting a small shingled roof 12x8. This home is 50 years old and the northwest corner has sunken about 4 inches. I would like to extend the porch with deck and add a sunroom encloser. How do I fix this or should I ignore it build the deck?

Three choices, none of them good:

1. Demolish the slab and build it right, meaning either support ALL sides on foundations, or NO sides.

2. Try to jack up the sinking side and place a foundation under it.

3. Ignore it, and build the deck over it, being careful that the deck is not supported on this slab in any way. Some professional design help may be advised to do this.

You could use steel piers. Check out thebasementguys.com they have piering info. and you can get foundaion repair contractors in your area to install them for you.

When we had to replace three walls of our basement the dirt from under the driveway fell into the basement. We filled as good as we could but had to have slab jackers drill holes in the drive and pump a clay/concrete mix under the slab. In 2 years we did it again and have had no other problems for 7 years. It cost around $200 each time but that was much cheaper and easire than replacing 36 food of drive.