I was looking at buying a house and the concrete in the garage sunk about 2" on each front corner, leaving gaps under the garage door.
I then realized that at least 5 houses on the same street had the same problem. They all had double attached garages with an upper floor extending over the garage. Built in the 1980s, in Edmonton, Canada.
What I guess happened is that the garage beams, which are presumably on piles, sunk a couple inches and pulled the garage pad and driveway pad concrete (all connected by rebar) down with them.
My questions are...
- What would cause this? Poor construction (too much weight, insufficient piles, etc)? Environmental conditions (flooding)?
- Is there much risk it will keep sinking if one poured a new garage pad, or will it have settled after 40 years?
- Is there anything else to be done to fix this (ie. jack things up and add new piles or something)