Engineered Clay Soil Foundation

[Dyerq]

I have a residential lot on which a 1.5 story brick 3800sf
house will be built. The lot is the end lot adjacent to
10 lots which have all been excavated for basements and
clay soil bearing is good. The project in in Charlotte
NC.

My lot was built back up in 2' lifts approximately 5' above the adjacent lots and compacted to over 95% which I had tested at top and down 2'.
I cannot afford to take the risk there might be areas
of poor compaction.

The house will be on a crawl space and I was thinking about
excavating to 2'3' above the non-engineered soil and
digging the footers. This would leave only about 2' of
engineered fill above the virgin clay which I could have tested at some interval. If I find any issues I could excavate down to the virgin (RED)clay and fill with gravel or concrete.


I had thought about using a poured in place concrete
crawl space wall and extra rebar in the footers also.

Does this sound like a low risk cost effective plan ?

Thanks in advance.

 

[BigH]

Hire a local geotech in your area and sit down with him and work out your thoughts and his advice. Clay fills can be problematic if not done right. Yours sounds like it may have been properly done, but . . . The geotech can check the records of the subdivision construction too - which firm did the work, how good, etc. A few dollars spent now may save you more money in both construction costs (in case you go overboard) and long term costs if problems.