The porch on my house was built partially over top of the basement/cellar, so it greatly distressed me a couple weeks back when my wife called to say that some sort of animal had chewed a hole in the porch floor and gone in there. Luckily, he got into the very small crawlspace and not into the basement. Once I got him out of there, I screwed some 2x4s over the hole and set out to thinking WTF I should do to repair it.
Because of improper sloping, water does tend to pool in some areas of the porch. This has contributed to some rot, and I want to just pull it all up and re-floor it. The question is, with what?
The existing floor looks like tongue-and-groove hardwood that has been painted, laid over top of 3/4 inch plywood. This does not seem like an adequately waterproof and water-shedding application. However, not being a dude who has rebuilt many porches, I am unsure of how I should proceed.
In short, my question is how do I build a water-tight yet attractive floor for my porch?
Decks are typically structures external to the house. My porch is over a livnig area (or at least, a storage area) so deck techniques probably don’t apply.
1)Proper slope, achieved by framing or mortar bed.
2)Waterproofing, achieved by roofing materials.
3)Traffic surface, wood, tile, stone, brick.
The waterproofing of choice is either 1) Sealoflex or similar paintable/trowelable mesh reinforced membrane or 2) a peel and stick tar based membrane, I don’t know the name of the big sheet, but any roofer is familiar with “Peel and Seal”, this is just a larger kind, or 3) a thick vinyl membrane like “Nobledeck” or similar.
Part of the deciding factor which waterproofer to use ties in with what finished surface. Tile will stick to Nobledeck, not Peel & Seal. Sealoflex requires a bondable top coating, Cemflex, in order for tile to bond. (I am a tileman by trade and I do tile and stone decks.) Wood I am not as familiar with, but I assume the wood cannot be nailed through the waterproofing (although Peel & Seal is self healing so it might be possible). I imagine the wood is put down over sleepers, suspending it above the waterproofer.
Confused yet? It’s a deep topic and fraught with peril should you ignore the basic requirements. Mistakes are not easily remedied. There is also a matter of flashing the waterproofer to the existing structure. It’s a combination of roofing/ carpentry/masonry. I’m sure there are other techniques (like hot mopped tar or cold sealing that could also work).
I would go the Peel & Seal route. The others can be tricky to seam properly, and I have used all of them before. Nailing the wood thru the waterproofer is immediately suspect to me, but it might be feasible, talk to a roofing supply house. I would still recommend sleepers to elevate the wood and prevent rot. But the waterproofer MUST have a vertical upturn at the house (flashing) and a downturn at the outside edges to prevent rot and water infiltration. Google around and post any questions.
I know about peel and seal, because I had to have a recent area of roofing replaced over a relatively flat area, and I told them I wanted that stuff (also typically called ice guard) on that whole section, as I was getting water infiltration. So that idea had occurred to me. But I don’t know what sleepers are.
Ok, I was finally able to get google to cooperate and show me some instances of a sleeper floor. I don’t know if I am going to be able to raise the floor that much without then also incurring the expense of a new door…and it’s already a cstom sized door because my house is old, so this would add a significant cost to the project.
I was discussing it with my dad last night, and we talked about plywood subfloor, covered in waterproofing like peel ad seal or that stuff they use to seal bathroom walls now. On top of that we were considering that trex-style decking with a corrugated bottom to allow for drainage.