Floor for shop

[jdw8320]

I am buying a house that has an old horse shed that would be a perfect woodshop, but it as a dirt floor. I dont want concrete. I was wondering how this would work first i a would cover the floor with plastic vapor barrier then then layout treated 4x4s around the edges and down the middle then lay 2x4s on edge 2ft on center with plywood for the flooring

[hermit]

I'll leave the real details to the experts, but I would put them 16" on center rather than 24, and I think I would use double layer of ply.

Todd

[siliconbauhaus]

How big is this horse shed mate? A 2x4 isnt going to span much of a distance especially with the weight of equipment on it.

[crokett]

I'm nervous about a floor resting on dirt, even with the plastic. I'd pour piers or at minium I'd use the concrete pier blocks you can buy and properly frame a floor. Those 2x4s will flex, even resting on the dirt.

[stormdog74]

I'm nervous about a floor resting on dirt, even with the plastic. I'd pour piers or at minium I'd use the concrete pier blocks you can buy and properly frame a floor. Those 2x4s will flex, even resting on the dirt.

Something like this inside your shed should work. Of course, where I live I don't worry about frost; I don't know if that would be a problem in cold areas.

http://www.shedfloors.com/index.html

[cwsmith]

I agree on not wanting any wood in direct contact with the soil. Even treated wood will absorb mosture and wick it up into the ply subflooring.

I'm not sure what an expert opinion might have for you, but I'd at least ensure that I have a gravel bed under the joists, to provide for drainage. I don't know how much headroom you have, but thinking that if it was a horse barn/shed, you may have enough higth to actually elevate the joist and put in redi-cast blocks and build a proper wood floor with ventilation. That may be cost-restrictive though.

CWS

[RodKirby]

I'm no flooring expert, but, I would caution against "going cheap". You don't want to have to do it all again after you've set everything up - do you?

The above posts sound like good advice to me.

[eddy merckx]

You've probably though about this already, but this would be a great time to design some troughs to carry dust collection pipe under the floor. If you're doing pier blocks, you'll have plenty of room. Just make the flooring above removeable in case of clogs.

Eddy

[Hellrazor]

I went through this with someone putting an addition on a shed last year. We spent as much money digging 12 36" holes, concrete, plus the hardware and using PT framing as we would have to do concrete.

What state are you from? My answer will depend on the typical weather.

[LarryG]

Building codes typically require all wood within 18" of earth to be pressure treated, because of the moisture in the soil. The code may not apply to your shed, but the reason for this requirement still would.

If it were mine, I think I'd pour a rough slab (i.e., no need for a smooth trowel finish) about 3" thick, then put down PT 2x4 sleepers, laid flat and shimmed level, then a layer of plastic, then two layers of plywood or OSB. This should last a long time and will give you a comfortable floor to walk on, which I presume is your reason for not wanting concrete (when I build my "last" shop, it's going to have a wood floor, too). It will also give you room to run electrical wiring, between the sleepers, if you need to. Eddy's suggestion about under-floor DC piping is worth considering, too.