Foundation Depth
9/2/2020 at 7:25:03 AM
Hi,
I plan on building a home at our lake possibly next year and I'd like to ask a couple of questions. We are located on Lake Clear Ont. on 100% sand and our water table seems to be around 5 to 6 ft deep in the spring. I would like to have a short basement with about a 6 to 7 ft in height. I had thought of 4ft down and 3 to 4ft above grade.
My question is - would I have to go at least 4ft down or deeper for frost protection?
If I add a couple of feet of fill would I still have to be 4ft from the original ground level or measure from the new level?
Being it all sand, would the house tend to move/shift every winter?
Thanks for your advice.
9/3/2020 at 11:01:42 AM
Foundation depths specified in the Building Code are dependent on soil type; with sand the requirement is minimum 1.2 m (4'). However lesser depths are permitted 'where experience with local soil conditions shows that lesser depths are satisfactory, or where the foundation is designed for lesser depths by a professional engineer'. If at the 4' point the sand becomes liquefied and unstable that would also be an example of where engineering would be required.
9/10/2020 at 7:41:26 AM
Check with the local building department ( you will have to anyway to get a permit) for min depth and footing size to support your house, they may be able to help. If that fails a soil engineer to check your plans is a good idea. Frost penetration is from the surface,native soil or suitable compacted fill, and if you need to cheat Pink or blue insulation can be used to make up lack of depth or for slab on grade buildings.
Houses only move around if you do the foundation wrong. Examples: soil settles (to small footing or not compacted) Frost gets under the footings (not dug deep enough or driveway beside the house)
Hope this helped
John
Search the TrustedPros directory and discover the best contractors in your area.
Find your home service pro
