When we moved in, the home inspector missed this (now) obvious sinking concrete pad atop the stairs to our basement. One day last fall when raking leaves, I stuck the handle into the crack at the base to see how deep the hole was and it went all the way up to the hilt. Same for a shovel, swallows the whole thing.
Looking at the arrangement a bit, the stones beneath the heat pump let rain drain through and the plastic tarp probably didn't capture all the water, instead funneling it toward the stairs, eventually eroding a huge cavity beneath them. The HVAC is about on its last legs, and when I replace it, I'll regrade the area and build a new pad. In the meantime, I dug up the edge and found the foundation piece was loose and no longer attached.
My question is: can I simply shove in a bunch of watery portland cement & sand to fill this hole enough to keep things from getting worse, rather than replacing the steps? A more intrusive DIY project might be to saw off most of the upper platform to get better access to the cavity, but even then can I simply fill the hole with concrete, rebuild the pad, and feel good about the repair?
I know another option would be to hire a mudjack or some such concrete lifting tool. I like doing things myself, so I'm hoping to avoid hiring someone unless that's what you all recommend...
Thanks very much for any advice! I'm in northern VA if that makes a difference to you.
Originally had a wooden platform which probably helped pool the water that fell on the HVAC ... maybe previous owners didn't have gutters at this corner??
Removed the wooden platform, getting a better look at the crack.
Despite being heavy, the lower portion of the foundation pulled right out.
Pretty decent cavity
Can see the back of the steps going down even. There is maybe 6" between bottom of the concrete and the stones/dirt.