suitable material and method to cover wood framed floor for exterior exposure
This is my first post so please bear with me while I try to be clear on the issues and parameters of the problem.
Part of an existing wood framed structure needs to be modified by removing the existing wood frame walls and installing headers supported by posts so that one portion becomes, in essence, an exterior porch. The entire structure shares a common 3/4″ plywood sub floor over 2 x 10 framing. The joist span is approx 11′; the space is approx 6′ x 11′ . There is an existing roof structure over the area and a basement space underneath that needs to remain dry.
I would like to find a waterproofing system and a material to lay over the wood framed floor so that the integrity of the existing floor structure can be maintained while exposed to weather. Is there a way to waterproof in order to protect the existing floor structure from weather? What might a suitable finish material be? For example, might a panelized wood deck be rested on a Bituthene or equivalent membrane that could be wrapped over the rim joists as well? The new beveled cedar siding would ideally cover the area of the rim joist protected by the overhang of the finish floor material. A stone or cemetitious product would also be considered.
Does anyone have any ideas, experience or recommendations on how to research the options?
Please let me know if yo need additional info to “solve the riddle”.
Yep, the most practical solution to your problem is some sort of rubber membrane, with a deck on top. But the devil is in the details -- you need some help from someone who knows this stuff pretty well.
As i understand the situation, you want an EPDM roof with a deck on sleepers over it. I have done and described thesse a half dozen times here, with photos in the past. Try a search for EPDM + Ipe` and see if anything comes up. Taunton lost a lot in the last change so I don't know what is still there.
Since this used to be interior, I assume it doesn't have any slope to it. Are there going to be any doors from the interior to this new exterior area? If so, you are likely to have problems with floor elevation... needing to raise the interior floor to match the newly-raised-and-sloped exterior floor. You could do EPDM rubber and sleepers, an elastomeric deck coating, a tile application like Ditra... but if you don't already have the slope you need, it will be a challenge.