Concrete patio deck
mtlion
| Posted in General Questions on
The steel beams under my concrete deck gets condensation every time it rains and drips on top of the furniture and floor bellow. The deck was built with steel beams frame according to specification and covered with two inch rib steel. I then put two inches of Styrofoam between ribs and then covered with a heavy mill plastic and finally poured four inches of concrete. Is there anything I can do to eliminate the problem?
Thank you Orlando
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Replies
A thin layer of closed cell spray foam will help.
A couple questions - which climate zone are you in? And you say that every time it rains, it condenses. Are you sure it's condensation?
There are a number of under-deck roof designs out there, both commercial and DIY. That may be one option, although it may be unsatisfactory if you've spent good money on a solid deck.
Have you considered it being a leak?
I'm no condensation expert, but my initial thought is, if you have a conditioned space, with some sort dehumidification, I'd bet there shouldn't be that much condensation...
In your described deck assembly, looks like the only waterproofing is the poly, and it's on the bottom of the concrete slab. Closed cell spray foam is not waterproof where it meets up to other materials, like steel.
How long has this been in place? When did the probalem start?
If you determine it is just condensation, I agree the easiest would be to coat the exposed steel with spray foam. Might even be worth a shot to try first. If it is a membrane leak you'd probably have to try waterproofing from the top of the slab.