Hello all, I am trying to put a floor in the basement of my barn in Western Mass., and would like to outline my plan and get thoughts on whether it seems sensible. I’m trying to make a workshop down there. Not trying to meet any code here, just going for somewhat comfortable and durable.
It is a fieldstone foundation with good concrete footings underneath. Right now there is a dirt floor. Occasionally the soil seems a little damp. Having a slab poured was too pricey ($3,600).
I plan to:
-Dig down a bit more for more headroom
-Slope the dirt slightly to the outside edges
-Put a trench around the edges sloped to a hole in one corner
-Put down polyethylene
-Put a perforated pipe in the trench that leads to a 5-gallon bucket in the hole
-Cover all that with a few inches of gravel
-Put PT 2x4s on edge on top of the gravel, 16″ on center
-Rigid foam between the 2x4s, spray foam around the edges
-Lay a plywood floor on the 2x4s
If the bucket fills with water I’ll put a sump pump in it emptying to a dry well outside.
What do you think?
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I'd suggest a slight variant on what you are proposing.
- Compact the gravel
- Cover with poly (keeping the poly above the gravel allows it to act as a capillary break).
- Lay a layer of continuous rigid foam.
- Either PT 2"x4"s on the flat with a plywood sub-floor.
- Or 2 layers of sub-floor on the foam.