Foundation Design Challenges on Expansive Clay Soils

[noeliaredondo20]

Hi everybody,

I’m working on a small residential project on expansive clay soil with noticeable seasonal swelling. We are considering shallow footings, but I’m concerned about differential settlement.

Has anyone dealt with similar conditions? What foundation types have worked best for you? Any tips on reducing moisture variation impacts?

Appreciate any advice you have. Thanks in advance!

 

[constructor123US]

Hey there!
Yeah, I’ve dealt with expansive clays a few times... definitely tricky stuff. If you’re seeing noticeable seasonal movement, shallow footings can be a bit of a gamble unless you really control the moisture. In one of my past projects, we ended up going with a pier and beam system to bypass the active zone altogether, and it held up really well over time.
That said, if shallow footings are your only option, I’d definitely look into moisture barriers and proper drainage around the perimeter. Gutters, sloping grade away from the foundation, maybe even a drip irrigation system to keep moisture levels more consistent year round, it all helps. Also, make sure the footing depth gets below the seasonal movement zone if possible, and use reinforced grade beams to help distribute loads.


Wouldn’t hurt to get a geotech involved if you haven’t alread... can save a lot of headache later on.
Good luck with it!!!!!!