A while ago, someone posted a question about how to waterproof a deck so they could store stuff under it. I looked, but can’t find the original posting to reply to, and he’s probably already done whatever he was going to do, but in the Lowe’s brochure in today’s paper, they have an “underdeck outdoor ceiling system” that consists of a corrugated sheet of plastic that seems to have channels under each joist. Could be a useful product if it works as advertised!
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Replies
Here are a few more Danno, just scroll down to the bottom.
http://www.deckmagazine.com/resources.html
I was excited when I saw your post because I'm building a porch which will have decking - not T&G flooring - over a storage space below. I've been trying to figure out how to keep the area under the porch dry (the roof will help but there is always blowing rain and melting snow in the spring).
All the below-deck systems assume that joists are perpendicular to the house. I built mine with joist parallel to the house so that my decking could be attached perpendicular to the house (looks nicer).
If you or anyone has some ideas for a home-made below the deck drainage system that works with perpendicular joists, let me know. If I figure out something and others are interested, I'll be more than happy to post pictures of what I end up doing.
Good luck; look forward to seeing the pictures. Yeah, unfortunately, the stuff I described is used when the joists run perpendicular to the side of the house. I suppose you could nail 2X2 "furring" or "strapping" perpendicular to the joists and then put this product on. I'd use PT or maybe even one of the new composition products for the strapping.
Can you hang corrugated roofing underneath the framing? It won't be very pretty, but it works. You hang it by fastening through 1 x 3, through the hills of the corrugations and into the framing. You build in a slope with tight screws on one end and slack screws on the other.
Ron
Ya. I thought of the same thing although I haven't seen that corrugated fiberglass stuff for a while - just the galvanized steel version (used for concrete slab support?)
e2canoe
Now you mention it, I haven't seen it for a while myself. (Note to self: think before speaking next time.) Of course I haven't looked for it either. There's always metal roofing although it costs the earth now. I have seen this job done like this. If your deck boards are fairly tight you won't accumulate a lot of junk up there. Some access for cleaning is a good idea, though.
I've just been talking to a customer about waterproofing a deck. It probably won't happen but we were talking about tile over thinset over a plastic support and drainage membrane (Schluter "Troba") over concrete over ply on framing. Big money. I think it's crazy. I can't imagine it would stand up to the climate with frequent freeze-thaw cycles.
Ron
> below the deck drainage system
I think you're just asking for trouble with that kind of thing. It'll fill up with damp crud and cause rot, mildew, mold, termites, mosquitos, etc. And how do you clean it out? If you want it dry under the deck, make the deck water tight in the first place.
-- J.S.
I had thought of using 1"x3" T&G Ipe decking but am chickening out. I am worried about how the wood will react to water seeping between the groove. Instead, I am thinking of just Ipe 1"x6" decking which means some water will drip below the porch.
In general I agree with your philosophy. I'll consider this carefully.
Maybe I'm lazy, but I installed some plywood sheets under my deck to store the lawn tractor and such.
I screwed in a set of eyes to the joists.
Screwes another set of eyes to the plywood.
Hung the end closest to the house with 2 chain links and the far end with a foots worth.
Water just rolls off, snow accumulates slightly.
Otherwise, it works fine.
I'll replace the plywood when it starts to rot.
Jeff
Not lazy. Pragmatic.
I think I'll try your method. Maybe I'll use PT plywood so that it last a bit longer.
The best answer I've seen for this, http://WWW.Duradek.com
Isn't this why God gave us plastic dropcloths -- to drape over the stuff we don't want to get wet?
Yeah, but he gave us wind and tiedowns.