Frost Wall at New Basement Walkout
Frost Wall at New Basement Walkout
(OP)
There is a remodel of an existing structure. The existing structure has a partial height basement wall and they will be excavating to install a walkout basement area. Therefore a new 'frost wall' is required. See attached sketch options. I'am curious what is the best way to do this. I suppose any of the options could work as the final grade is still above the bottom of the existing footing. Any comments are welcome.
Also I'm curious if anyone has used insulation to avoid having to excavate the full depth?
Thanks
Also I'm curious if anyone has used insulation to avoid having to excavate the full depth?
Thanks





RE: Frost Wall at New Basement Walkout
RE: Frost Wall at New Basement Walkout
EIT
www.HowToEngineer.com
RE: Frost Wall at New Basement Walkout
Is it acceptable to pour the concrete frost wall directly adjacent to the existing footing or would it need to be underpinned?
My reservation with placing the new wall next to the existing as opposed to underpinning is that -> is it possible for frost (well heat actually) to travel through the new wall so that the soils directly under the existing wall freeze?
EIT
www.HowToEngineer.com
RE: Frost Wall at New Basement Walkout
Your left hand #1 option could use some support improvement, since your new "frost wall" can lean sideways from the effects of the footing.
Green sheets of insulation should be covered with mortar or other to prevent ulta V degradation.
So, I say, why all this grief, when you can set your slab on closed cell insulation?
RE: Frost Wall at New Basement Walkout
I'd suggest a variation on the vertical insulation, using "wing" insulation, also mentioned by OG. The principles are pretty well established, are covered in ASCE 32, "frost-protected shallow foundations". Two-inch thick insulation would wrap around the footing, then extend horizontally about 4 feet at the level of bottom of footing.
RE: Frost Wall at New Basement Walkout
Thanks again!!
EIT
www.HowToEngineer.com