I am building an 8x20 insulated porch/addition to my home
in the northeast USA. The house has a full basement but I
planned on putting the addition on concrete piers and either
insulating the floor or putting an insulated skirt around the
perimeter. Then I talked to a neighbor who has been building
up here for decades and says just sit the whole thing on a
20 foot PT 8x10 or 10x12 on the ground (which is all sand
around my house). Lay some 2' pieces of PT 2x10 under
it every 6' in case it ever moves or shifts you can easily put
a shingle under there. He says concrete doesn't work well
up here because it cracks and shifts, but the buildings he
has built just sitting on large PT timbers generally stay level.
There are lots of big old barns around here that are just
sitting on big timbers resting on flat stones.
Is it OK to do it this way? I am in a part of Vermont where there
you can build things pretty much how you want. Thanks,