GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Void/hole under support column – poly foam injection suitable solution?

raphaelb | Posted in General Questions on

Hi there,

I recently bought an old (150 years) house in CZ 5a, that has a partial basement and then lots of crawl space. The crawl space needs a lot of help – there are rodent droppings everywhere, ripped up vapor barrier and batting insulation, random junk, a possum (which I have removed already) 

I had a crawl space / basement company come quote me for an encapsulation, and while he was down there looking at it, his knee sunk about a foot into the dirt right between two support columns. 

There appears to be a tunnel (I’m guessing from rodents but I have no idea) or some kind of void in the dirt, and unfortunately right underneath the support column. 

See pictures below – the one from within the hole I took by sticking my hand down into it with my phone. The top of that picture is the bottom of the support column. 

The company proposed drilling 12 holes 5 feet apart and injecting poly foam into them to fill any voids and reinforce the soil under the columns. Based on my reading here and elsewhere that seems like a reasonable solution, but thought I’d ask if anyone else has had anything similar or has any suggestions. 

Going off towards the other way from that column is another 5+ foot tunnel/hole, I just can’t get a good photo of it since it’s narrower than the one in the photo. 

Thank you in advance for any suggestions!

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |