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kkehler
Garden Shed Sheathing & Bottom Plate Contact Soil / Sod

I'm preparring to build a garden shed on an old existing slab once used for basketball. If I use pressure treated 2x4 for the bottom plate, do I need to worry about rot? The grade of the yard will cover the bottom plate and up to 2 inches of sheathing.

dj1
Re: Garden Shed Sheathing & Bottom Plate Contact Soil / Sod

Pressure treated is not a life long deal, so keep the wood off the soil as much as you can. Sitting on a slab, it's probably good for 20 years, give or take a few.

ordjen
Re: Garden Shed Sheathing & Bottom Plate Contact Soil / Sod

There are multiple grades of pressure treated wood. Get the highest rated version. If you can keep the earth from actual contact with the wood, you will gain longevity. Also, consider placing the self-stick butyl banding to the bottom of the boards so that they are not in direct contact with the concrete. This is the stuff that is often put over deck joists before the decking goes down. The closed cell foam seal, which is used under walls when they are set, would also keep the wood isolated from the concrete.

Mastercarpentry
Re: Garden Shed Sheathing & Bottom Plate Contact Soil / Sod
kkehler wrote:

I'm preparring to build a garden shed on an old existing slab once used for basketball. If I use pressure treated 2x4 for the bottom plate, do I need to worry about rot? The grade of the yard will cover the bottom plate and up to 2 inches of sheathing.

From what I read, it seems you intend to cover part of the wood with dirt- and that is not a good idea even with treated lumber. Either raise the slab or re-landscape to keep the dirt and water away and it will last much, much longer. Adding height to the slab with more concrete will likely be the easiest good solution here. Otherwise your non-treated wood components will rot and the floor will become awash in a heavy rain. Whatever you do, keep dirt and water away from wood (even treated)and it will be happier and last longer.

Phil

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