How do I stop further deterioration of T-111 wood siding
I caused the problem when I added a deck to my home, lag bolting an exterior rim joist for deck support directly to the interior rim joist with the T-111 siding sandwiched between (stupidly). I recently discovered that the sandwiched T-111 is starting to decompose due to water retention. Removing the exterior rim joist to make repairs would require dismantling the deck, which I hate to even think about. Question 1: If I can ensure that the T-111 won’t be exposed to further significant water (through siding), will I have already set up a “dry rot” situation that will eventually compromise the underlying structure? Question 2: Assuming the answer to question 1 is “yes”, is there any thing short of removing the outside rim joist and replacing the T-111, perhaps an oil based preservative that could be applied at exterior joist/T-111 interface that would penetrate the degraded siding and arrest further decay? Thanks for your help.
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If your situation is like mine (and it sounds like it) you wouldn't have to dismantle the ENTIRE deck. Our decking runs parallel to the wall. We will pull up 3 feet of decking, and place a temporary beam 3 feet from the house to carry the load. Then we'll dig into the ledger and wall problems. Haven't decided yet whether to hang a new ledger with a gap and flashing attached to the house, or else turn that edge of the deck into a cantilever with some new supports close to the house. In any case, we don't have to dismantle the whole thing, just 3 feet of decking, and we'll put it back down when done.
Good luck
Pretty hard question without pics / seeing it
Siding won't fix the issue - proper flashing will & maybe enough to help prevent further damage
If you have to remove / rebuild, first make sure it is flashed properly , go with a stand alone deck, or use a product like Deck Spacers
George,
You cannot arrest the rot. You will have to remove the existing deck ledger, regardless of what is involved, remove the rotted T-111, check for rot in the house rim joist and repair as necessary, and then properly flash under the T-111 and over a new (or reused) deck ledger. Rhino plastic deck flashing will stand up to the chemical treatments in the deck wood better than tin or aluminum flashing.
If the T-111 is disintegrating, then it's likely that there's rot in the house framing as well.
A deck ledger needs either to be spaced or flashed with Z-flashing. I prefer the flashing, since bolting tightly to the house creates a stronger connection and exterior decks have to be engineered for at least 60 psf live load, and more if there is any possibility of impact loading from snow off a roof above.
http://www.finehomebuilding.com/how-to/articles/get-your-deck-off-to-a-good-start.aspx?ac=ts&ra=fp&collection=72676