hi. I am going to start on repairing a NOT to code foundation. Long story, but this is a very large, with NO PERMITS addition a guy put on my home. he then renigged in the buying of it, and I am stuck trying to make it right now! there are a FEW large items I want to do, then hopefully it will look a little better to the inspectors.. and I will get them out here to give me THEIR list! I know, the foundation is not adequate. The addition is a two story, app. 25 X 80. the depth is 24 inchges, I am told it should have been 36? how abot the width? hey. also, I want to build a false chimney on the side that shows how NON SQUARE he did it! Their really is no way to actuallty REPAIR that, without it costing upwards of 25,000, so I want to BREAK the wall you look down.. anyone ever done this?
Check with your code guy. He can tell you what can be done wothout removing the foundation. Ask him about a shallow insulation method that is in the code.
You will have to dig and place rigid foam against the foundation and horizontally out from the foundation wall.
At the same time, you can verify the typical footing width and the soil type at the base of the footing. Even if the footing is not as wide as the code minimum, an engineer can sign off on a narrower strip footing since the required width can be engineered to get around the prescriptive code requirements. An engineer may require a couple of shallow hand auger samples, but it sure beats replacing the footings.