shed floor

11 Jun 2011
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United Kingdom
My partner is about to build a new shed. We have a concrete base built and he has said that this will be the floor of the shed and that he does not need to build a raised wooden floor. He has said he will secure batons to the concrete base and the walls of the shed will be secured to these. I am worried that the concrete floor will become damp. Please help as I do not want a damp shed.
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Providing the overlap planking of the shed, is outside the area of the base, by a small amount, it should allow the water to run off, without entering the shed.
But bear in mind, concrete is very cold, and if the shed is to be used as a workroom, then an insulated floor should be laid, damp proof membrane with waterproof plywood on top, then possibly some vinyl floor covering.

as said the shed needs to overlap also the concrete needs to be around 2" higher than surrounding ground to stop rot in the wood and heavy rain entering
any wood directly in contact with the concrete will be subject to rot if any water or damp remains for extended periods

is the concrete fully above the surrounding ground??
i personally think you need to put battens down and a plywood/osb type floor in.. imagine stood any length of time on a frozen concrete block?! Get a floor in and keep the moisture and cold out!!
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Thank you for your replies. The concrete base was laid by the previous owners and is the same level as the surrounding lawn, so overlapping is not possible. Partner thinks that if he puts a membrane under the edging wood and then seals it with a waterproof sealant then it will stay dry. I think that the water will lay flat on the surrounding concrete and will seep underneath. the concrete base is level but is slightly ridged and I cannot see how you can prevent any water getting in.
you could dig a moat around the base?

I think you're right, water is relentless and will eventually get in... you have to be off the floor.... get your partner to google other shed designs.... they'll all be the same?

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