An idiot who wants to dig out his basement.

That about describes me.

My basement is mostly made of dirt. 5 feet deep in someplaces, 4 feet to 18 inches in others. I want the entire thing dug down to 7 feet from floor joists to basement floor.

I have been told that I can save a lot of labor costs if I dig out the basement myself. What I want to know is, how much should I leave around each foundation wall to keep the house from caving into the basement?

I am thinking to have a contractor do this - dig it out, rebuild the foundation walls, and pour a concrete slab, will come out to somewhere around $20k. I am not sure how accurate that is.

Any comments, suggestions, or advice?

Thanks

 

I can't give you a price (size of basement, local, etc.). However, I can tell you what my brother-in-law did with a little engineering guidance. He dug to the level of the basement walls. Then dug a 3' wide pit under one wall, and cast a concrete plinth. stiff grout was used to join the old wall and new plinth. This was repeated around the perimeter, skipping 3' each time. After the plinths were in place every 3 feet, the remaining areas were excavated, one at a time, and concrete placed as before. After the entire basement is supported, the basement was excavated down to the new slab level.

This is not quite a DIY project, and the actual basement walls, footings, and soil type may differ.

 

I did something similar to that about 6 years ago although my cellar was already partially done. What worked good for me was to dig down in strategic locations and place adjustable jack posts under my sills, about every 6 feet or so. Then I went ahead and dug out the rest of the cellar. When it came time to put up the concrete walls I just poured right around the jack posts. I left enough room on mine to put on 2 courses of blocks but you can form right up to the sill if you want. I felt it was easier to place the windows where I wanted them that way. I just hope your digging is better than mine was, I took out some rocks(with the help of a backhoe) that were about half the size of my car....... Good Luck.

 

Call your contractor. The price is right on the money. I have just finished my third one in the last 60 days where home owners had started and found out what a job it is. Yes, there are those who have done it themselves, but if you do not have the time, or the committment, hire it done. It will take about 10 days and be all done. One thing to remember, if a contractor does it, and something does go wrong or a wall fails, his insurance will cover it. If you screw up, your sunk. Good Luck