I did a search but couldn’t come up with the answer to my particular question.
I’m preparing to side over OSB sheathing covered with TYPAR. I will eventually build decks on two sides of this structure and would like recommendations on the best way to place and flash the ledger boards.
Seems to me that I should lift up the TYPAR, lag bolt the ledgers directly into the OSB/covered band joists, then flash over the edge of the ledger, with the vertical leg of the flashing UNDER the TYPAR, then side down over the TYPAR to the flashing.
OR would it be better to first side over the TYPAR, then attach deck ledger through the siding?
I’ve attached decks to already-sided structures before, using stand-off blocks between siding and deck ledger and caulking between the block and the siding, would like to take atvantage of my first opportunity to improve on that technique.
Edited 3/31/2004 3:30 pm ET by johnnyd
Replies
If you want zero water intrusion risk the best bet is free-standing.
Still, a properly flashed ledger can be effective as long as you strip the siding and flash properly. You are correct that you should tuck the flashing under the housewrap. A good addition would be ice and wate shield behind the ledger adhered directly to the OSB.
Jon Blakemore
Thanks. Yes, and I suppose the ice and water shield would also seal against intrusion through the lag bolts. Also, this is a pressure treated wood foundation, so the band joist is treated to .60. Ledger will be left-over .60 treated 2X10.
I'm about to put a deck ledger on my house (the wall is stripped to sheathing right now) and here's how I'm going to do it.
1. Install the first course of 30 pound felt.
2. Install the ledger over the felt, using 1/2" x 1-1/2" rips of PT as spacers where the lags are (every 32"), so that there's a 1/2" space behind the ledger. The top of the ledger is about 27" off the mudsill, so that the first course of felt will go above it by 9"
3. Install a custom galv Z-bar flashing over the ledger. It will be 4" up, 2-1/8" out, and 1" down.
4. Install a strip of 12" vycor (peel-n-stick) over the top flange of the Z, up onto the wall. This will master the top of the felt by about 3"
5. Install the next course of felt down to about 1" above the Z.
6. Make crosscut kerfs 1/16" deep in the bottom of the first piece of decking so that any water that gets behind it can get across the Z and down more easily. The decking will not be up tight against the vertical leg of the Z. Water will still sit under that piece of decking on top of the Z more than anywhere else, but them's the breaks.
7. Install the first piece of siding (shingles, actually) about 3/4" above the decking. If I'm feeling especially thorough I may install a kickout flashing behind the shingles so that any water running down the wall is directed a few inches out onto the first deck board.
Edited 4/2/2004 3:05 pm ET by davidmeiland
Wow...the belt and suspenders approach. Seeing your location, I can understand...how much rain do you get a year?
I suppose you have also done alot of rot repair/replacement to come up with a system like this.
Good to see it laid out in steps like this...some of which I'll utilize. Thanks