The basement continued: The quest for more headroom

Categories: Construction - Tags: apartment, basement, bench-footing, ceiling height, income property, lowering, underpinning

Things are moving along in the basement. We decided to use a bench-footing technique to gain more headroom. For those of you unfamiliar with the term, “bench-footing” is similar to “underpinning” which are both basically just fancy pants construction words for the process of lowering the basement floor. A house’s foundation is tricky business. You can’t simply dig down a basement floor without reinforcing the structure because the weight of the house would cause the foundation walls to slide inwards and crack the walls above. Yikes!

Here’s a diagram that shows how a new ‘bench-footing’ style foundation is created off of the existing footing to lower the floor while reinforcing the structure. Because yea..I TOTALLY understand construction drawings now…

Unlike underpinning, where the structure is reinforced directly underneath the existing footing, with the bench-footing method, the structure is reinforced by stepping inward from the foundation walls, then digging down to the desired depth, and constructing new concrete footings for the new deeper floor. The new walls then extend up to the original basement floor depth, and as a result, you’re left with the effect of a concrete bench extending along the perimeter of the reinforced foundation wall.

Whether you’re awesome like me and understood the structural drawing or even any of the explanation above or not, the take away is that when all is said and done we’ll have a lovely 8’6″ ceiling height instead of the ‘passable’ 6’11” that was existing. I say passable, because 6’11 would have satisfied the building code requirement for a basement apartment, but let’s be honest. Would you want to live in an apartment with a 6’11” ceiling?? Probably not. And we’re betting that not too many of our potential renters will either. As for the concrete bench – granted it’s not 100% ideal, but the time & cost saving benefits of the bench technique faaar outweighed the aesthetic & space gains of underpinning. And – with a little ingenuity, we’re pretty sure we can design around it.

DISCLAIMER: This is NOT a DIY endeavour. I use the word “we” a lot in general terms, but when I say “we” I really mean Team Dreamhouse on the whole. Since any changes to the foundation of your home run the risk of permanent damage, you should never attempt to lower your basement without consulting a reliable and well qualified professional.