We are going (wanting) to install an open deck from our master bedroom on our 2nd story over the first story game room. The deck railing is walled on three sides and I will have to use scuppers to get the water out. All construction has been accomplished with an engineer but I am uncomfortable with the sealing of the deck and potential water leaks. Other than don’t do it, any suggestions?
Thanks RPS
Replies
First off, welcome to BT.
Other than don't do it, any suggestions?
Sure.
First off, build a draining, water-tight roof "first," make the deck secondary to it.
Second, the deck will be much better over the life of the building if it is removable.
Now, since you are using a parapet wall, I'd likely detail the roof like a commercial low-slope roof. This would slope to your scupper drains. The deck would then "float" above that, with conncetions only to the side, parapet wall as much as the deck design would allow. That "uncouples" the deck from being a roof surface, which makes the roof and the deck much easier to live with. Now, that might mean having the parapet wall a bit taller than it "looks" right now on the drawings--but, that's not such a bad thing, either.
Consider bringing the fascia detail around the parapet, too--this makes a good place to have the scuppers line up to (the scuppers will need to project out a bit further to suit that, which is also a good thing, that keeps them from washing down your wall quite so much).
You have not filled in your profile (at the top center of the screen "update profile" appears in grey, click on that or your RPS in blue to enter Profile info). If you are in snow country, you will want more ice dam protection where the scuppers punch through the parapet walls. That could mean using ice & water shield 12-18" up the inside of the parapet, and a long lap of the roofing membrane, and, likely, a counter-flashing strip of roof membrane back over the joint.
If you are in the Pacific NorthWet, you probably ought to break down and get a collecting downspout for the scuppers, if only to control where the runoff collects at ground level.
If you are in Pine country, you will absolutely need access under the deck (like hinged panels) to be able to clean out pine needles that just won't quite wash off, ever.
That being said, the parapetted deck is likely to be a nice feature on the house. It will likely be a much better idea than trying to have an open-railed deck in the same location.
That help any?
The downside to the two-surface approach is maintenance, cleaning between the deck and the watertight surface.
The downside to a single-surface approach is that you have to slope it to drain properly. There are products, though, for doing it that way:
http://www.duradek.com/
Your climate and surrounding vegetation are important considerations.
-- J.S.