I was wondering if folks more familiar than I with pole-style construction could clear up my confusion:
(My apologies if this seems like a stupid question or is based on some fundimental misunderstanding of pole-barn style construction…)
Given that I often hear of pole-style construction as an option for heated workshops and other spaces that could essentially function as homes, I don’t understand how frost heave is not a danger. How does the space between the pole/posts (where there is no footing) prevent frost heave either at the exterior wall or under the slab near the wall?
I haven’t been around these buildings enough to learn (I’m city) but I’m always on the lookout for a simpler footing/foundation system.
PS I’m in 42-48″ frost footing climate
Thanks.
Replies
nanny.. my take is the poles are set below the frost line... so they don't heave..
the slab is a thickened edge slab.. basically floating.. it probably heaves .. but uniformly. so no one notices...
at least i never have ...
but hey, whadda i no ?
Mike Smith Rhode Island : Design / Build / Repair / Restore
OK,
But if the slab rests under the "sill" of the exterior wall, then any heave moves the wall, right?
If the slab rests only interior to the exterior wall, then the exterior wall must come into contact with something - and that something must be suseptible (sp?) to heave, right?
I don't understand how a finished interior space in a frost climate would be safe from heave danger. I must be missing something.
don't know.. on pole barn const. if the interior is heated we use a thickened edge slab isolated by 2" of foam..
on unheated structures the thickened edge is about 12" say 8" below grade..
our frost design depth is 40"
maybe one of the things that protects us is we scrape the area of loam.. and lay down an 18" pad of bankrun gravel ( looks like coarse sand with rocks in it )... so this is what's under all of our structure... with some contamination when we dig the post holes.. possibly this granular material is protecting us from heave ..
all i know is we've used pole barn const. for about ten years and never had trouble with frost heave..
now , this winter was probably the most severe frost in about 15 years.. so i'll let you know if i find any problemsMike Smith Rhode Island : Design / Build / Repair / Restore
I'm still confused, but thanks for the responses anyway :-)
Seems to me if there were no real danger of frost problems, more standard housing where basements were not called for would be built this way.