Is it possible to ICF as a 2ft foundation for an extension in a 4foot freeze area (up state NY)
The extension exists as attachment to house not a lot of weight, just starting to sink.
Thanks for replies
Is it possible to ICF as a 2ft foundation for an extension in a 4foot freeze area (up state NY)
The extension exists as attachment to house not a lot of weight, just starting to sink.
Thanks for replies
Framing the floor inside a crawlspace foundation keeps a gable-end addition close to grade.
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Replies
If you want a foundation to be stable in an area that experiences freeze conditions, it has to extend below the freeze depth for the area. (it also has to be of proper area so that the undisturbed soil beneath can support the total weight of and on the foundation.
So if you mean to use the ICF for a two ft wide foundation, that is 48 inches tall, and buried to the top, yes.
If you mean two feet tall, better plan on two of these stacked on top of each other, (and located so the top is level with the ground surface)
Close to the house, foundations also need to couple to the house foundation.
Thank you for you comments it is appreciated, needs more work but do it right the first time always right.
Depending on what this extension really looks like, it is also possible to securely attach one end to the house, and the other end on a wall or posts, each of which would have to be anchored below the frost depth, and not attach the base of said wall or posts to the house foundation. (assuming and depending on the structure of this extension)
What exactly are we discussing? do you have any photos you would want to share?
You could take a look at frost-protected shallow foundations - FHB has done at least a couple articles on them relatively recently, and a guide for them is available here: https://www.homeinnovation.com/~/media/Files/Reports/Revised-Builders-Guide-to-Frost-Protected-Shallow-Foundations.pdf. It should be possible, but might require some modifications to the ICFs, as well as insulation beyond what’s in the ICFs.
Perhaps a sketch of what you're trying to do would be helpful.
One person's 'word picture' is just not enough for others to fully comprehend.