Imagine a main floor that covers 1000 sf. The floor above it covers half of that and the other half is a deck that’s used as an uncovered porch. I’m trying to learn what has worked best for y’all for waterproofing the porch so that there are no leaks back into the second floor room or down into the first floor through the porch deck/ceiling. Want to actively use the porch, so regular flat roofing solutions might not apply be/c some of them aren’t meant for regular traffic.
Some possibilities I can think of:
1. Elevated slab, with porch portion sloped away from the second floor wall. But how to waterproof and still have it be a good sun deck?
2. Elevated slab, with porch portion poured an inch lower and also sloped away from the second floor wall. But how to waterproof and still have it be a good sun deck?
3. Framed floor. But what’s the best waterproofing of the porch that’s also a livable and attractive porch floor? And the framing could slope away from the 2nd floor room, or be an inch or step lower, or….or…or…
Pros and cons to each. I’m wondering what arrangement you’ve seen that you think works best.
Replies
Recently, I have worked on two projects similar to what you're describing, but in both cases the flooring is tile.
Project one is a covered second story porch over 1st floor living space. In this situation, I installed perimeter flashing (from the floor decking out over the brick veneer) over which a pourable membrane will be installed over the entire floor and a mudset tile job will be done over the membrane.
Project two is a covered second story porch open on the first floor. We installed a flat seam copper membrane on the floor leading to a small built in gutter at the front edge (actually, just a 2" wide by 3/4" deep trough) that drains through 3/4" copper pipe to the inside of the columns. This trough is filled with gravel and a mudset tile job will be installed over the whole thing.
Hmmm, interesting. Thanks. Do you remember how it was framed? Did the structural members extend from the covered area to the porch, or were they independently framed? Were they able to keep a consistent ceiling height on the first floor, or did it step? Were they able to keep the walking surfaces on the second floor even, or was there a step down or up as you went from inside to the porch?
Edit...And did the porch deck slope or was it truly flat? If flat, what about puddles? If sloped, could they do small enough slope to be comfortable for people and yet still drain?
Edited 9/25/2002 3:30:14 PM ET by Cloud Hidden
In both cases the tiled area was covered (a roof over) but three sides are open to blowing precipitation. They are both conventionally framed with level ceilings. There is a slight slope (probably 1/8" per foot - either achieved by ripping a wedge off of the joists or adding one on - The decking was on before I arrived in both cases) and there is a slight step down as you enter the porches from the heated spaces. As far as puddling, the tile has not yet been installed, so we'll see.