how do I dig a crawl space out and make a basement with concrete and block?

Question

to support a second story house

Answer 1

I lifted a garage a few inches and laid a concrete floor in sections and then lowered the garage onto the floor to comply with "you can repair it in place, but if you tear it down you have to move it to comply with new zoning rules" that would have taken out half my yard.
I have leveled my own house, bit by bit, in the crawl space.
The idea of supporting a house from the edges while you dig out the middle scares the h... out of me. You would have to analyze the structure and move long and heavy steel beams under the house, then dig in such a way that the supports for the beams did not collapse (with you under them)
I found that the (supposedly professional) people who put reinforcing beams under my house did not understand the structure. If your house has a center support and edge wall support as mine does, then your basement has to have a row of support columns down the middle, further complicating digging and foundation work.

Answer 2

Dig Out Crawl Space

Answer 3

My Dad did it in the house we lived in when I was a kid. He dug out a 3 foot wide area under the foundation, built a forn and filled it with concrete he mixed in a cheap Sears mixer. After it hardened he would move on to the next 3 foot section. He worked on it most weekends and it took 16 years, and thousands of wheelbarrow trips, but it turned out fine. He Even put in a Bilco door and mixed and poured slabs for a floor.

It's a massive job, but it can be done.

Answer 4

Normally the house is temporarily supported by steel beams while an excavation is done underneath with a small skid-steer loader. I have also heard of doing it with manual labor (lots of wheelbarrows), and I have heard of it done utilizing vacuum excavation.
A new foundation is poured or built after the excavation is made, and the beams are removed.
It is not a job for an amatuer.

Answer 5

This is not a job to be tried by a home handyman. You need a builder who specializes in this sort of thing. The house has to be properly jacked up and supported while the work is being done.

Answer 6

call a masonry contractor who has done this before...not cheap but it is done all the time...

Answer 7

If you are on a slab it is nearly impossible, but if you are already on some sort of crawlspace there are ways to lift the house. Check to see if there are any house movers in your area.

Answer 8

You probably could do it your self as someone already suggested, But with all the bulding codes they have now days it would be best for a professional to do it.