I'm considering digging out my basement to increase headroom since the ceilings are between 6'5" and 6'7". I want to know if it's possible to dig down the required 5-7 inches for a finished space without needing to underpin. Just to clarify, I'm not starting any work yet—I plan on hiring a structural engineer to handle everything, but I'd like to understand what I'm getting into before reaching out for quotes.
4 Answers
Honestly, the safest bet is to hire a structural engineer for this. This isn’t a DIY project—wrong moves could leave you with serious structural issues.
You can generally dig down quite a bit if you do it right, but the exact limit without underpinning really requires a hands-on inspection from a qualified expert. Just keep in mind that proper methods are key to maintaining safety.
Thanks for the insights!
If your foundation isn’t too old, it probably has thick footings. As long as you stay above that, you should be okay. If your house was built in the 1920s, just be cautious of the ledge in your area—digging might not get you very far if there are rock formations.
First things first, check what type of foundation you have. If it's a rubble foundation without a footer, you're better off benching rather than underpinning. For block foundations, knowing the depth of the footer is crucial—don't dig below that. It might be worth considering redoing the rat slab instead of digging. Also, you could think about lifting the house to create more headroom; it's probably the safest option if you hire a good crew.
This advice is really helpful, thanks!
Lifting sounds like a good path! But watch out for existing utility connections—they might need adjustments.

I won’t be doing any of the work myself; just trying to see what's feasible before I get quotes.