Great building srleen2.
Wouldn't pass here. No wood to soil contact allowed for termite and critter intrusion.
This is also part of the reason for the curb, keeps your wood high and dry.
I can also hose out the building floors with out getting wood or dry wall wet.
On code thoughts, I see a lot...
I think you are asking why double thickness.
Some codes only require 3" thick slab and no curb.
I pour 6" in the centre with a perimeter beam curb 24" from top of curb to bottom of slab.
You can go with code for your area but it is usually minimum for strength.
residential codes are not designed...
After building a few with attic storage I would suggest you not do attic storage, instead do lofts at the ends of garage like above the overhead door.
most attics end up with lots of stuff that you have no idea you still own after a few months.
with a loft style you can see most of what you have...
I am in Toronto and I build garages for clients. Best bang for the buck is a really well formed and twice as thick as code calls for floating slab with a 5.5x5.5 perimiter curb. Before the pore under the slab is when you would add your insulation and vapour barrier, also ad the ridgit foam...
I have the height problem in a big city where you are allowed 13' exterior height, I needed 10, inside for a lift.
This is what I came up with to keep the neighbors happy and conceal the height from the nosy ones.
Outside max height is 13'6" inside height is 10'3"
the height from foundation to...
Building with osb on an interior to me is way scary and illegal here in the city of Toronto.
5/8 min dry wall for fire and way easier. Screw Mud Prime Paint, all water based.
I just build a new garage and had to go with ten foot ceiling, here in the city they wont let you go over 13 ft exterior height.
I hope I can get two Mopars on a lift.
Challenger and ******* for now.
Any thoughts?