Considering the options for my 10 X 12 shed foundation: the builder offers pressure-treated wood runners, and I'm torn between placing them directly on the concrete or raising the shed slightly. Both options involve pressure-treated wood. The floor will be insulated with spray foam and have a subfloor. Any advice on which route to take?
Planning to build a 10 X 12 shed. Wood straight onto concrete, or raise slightly?
- Thread starter WhyKnot
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did you install a skirt or leave it as is? any pics?
never ever ever lay wood on concrete always a minimum 12mm [preferably 25-50mm]then waterproof layer in other words something that wont be effected by water on the concrete to space the wood then a layer to double insulate the timbers to keep it dry
the cladding on the sides should drip off the base in other words shed should cover and protect the base so no water should in general ever get on the concrete
the cladding on the sides should drip off the base in other words shed should cover and protect the base so no water should in general ever get on the concrete
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I've read people using skids, and as long as they are PT, the chemicals should prevent the wood from rotting as quickly. What product do you recommend for shimming or spacing the wood from the concrete slab? I am not finding much online as most just lay it down.
this was the beam I used, bump on the inside edge, slope helps water run off/out
Composite Profiled Foundation Beams
These composite foundation beams are suitable for all log cabins. Featuring a 'profile to allow water to drain away from the base, from Tuin UK.
www.tuin.co.uk
The bearer beams were pressure treated just to help it along, the overhang of the roof helps keep the worst of the rain off the base except when its too windy.
they may work but need to be empty cell as in no stones or pebbles
they may work excellently on solid slab with joists as any high points will tend to have a greater load so crush/deflect/compress until load spread sideways i dont know but as a unknown to me material may start to fail before the shed or structure does
If you're making a concrete slab, I think the best option would be a dwarf brick wall that the shed can stand on, with a DPC.
This will prevent any wood being in contact with the damp base, and give you a void that can be ventilated to reduce damp.
This will prevent any wood being in contact with the damp base, and give you a void that can be ventilated to reduce damp.
It's not needed in my eyes and will remove the "give" that can help even out any high spots
And whilst moisture transfer is less likely leaves and crud is more likely to build up on a full matt and hold moisture
If the timbers are treated and protected from wet wrapping them is a bad idea as air flow dries and wrapped holds moisture in
Ok thanks
I thought that with without the gravel they might not be strong enough.
Also I meant to only wrap the bottoms and about 1 inch up the sides of the supports ?
They are after all under the shed where your not going to get much water at all I would think.
I think when I build my shed this year I will experiment a bit.
Mike
I thought that with without the gravel they might not be strong enough.
Also I meant to only wrap the bottoms and about 1 inch up the sides of the supports ?
They are after all under the shed where your not going to get much water at all I would think.
I think when I build my shed this year I will experiment a bit.
Mike
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wacked MOT and then concrete lintels laid over at 90 degrees to the bearers. This is what my shed supplier recommended a few years ago (they supplied and installed). No need for a concrete pad for a shed they said. They were right - it's been fine.