floating deck- waterproofing details against home?
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Hey Ya’ll
I don’t usually build “floating” decks but am looking at doing one right now for some particular reasons on this structure. The intention would be to build it without actually fastening to the home via ledger board-but rather just frame the deck right up to the edge of the house (with some breathing room for airflow and no wood on wood contact to the siding, etc.)
On this front-I’m wondering if anyone has any waterproofing details for the space between the siding and where the decking meets the wall.
Should I just leave enough of a gap (3/8 or so?) so water and air can flow down between my decking and the house and call it a day?? Or should I be thinking of some kind of hard 90 degree or z flashing tucked up under the siding and onto the deck framing similar to a Z flashing over a ledger board?
Wondering if because the deck is floating-an air gap would be sufficient or wether I should be looking at some kind of hard flashing to address the wall to decking connection/relationship(in how water trickles down the siding and down inbetween the deck framing and the siding) even though the deck is not affixed to the home and there is a 3/8-1/2″ gap between the deck framing/decking and the siding.
The deck will be on a wall with an in swing entry door and deck height will be set a few inches below the door height…don’t think thats very relevant though.
Any two cents, details, etc. are appreciated.
Nick
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Replies
I'd go with a gap but more like an inch.
Agreed--that's what I did and it's worked out very well.
Nick,
The further you can put it away from the wall while making sure the gap isn't a safety hazard the better. One disadvantage of freestanding decks is that the siding behind the floating ledger is inaccessible for re-painting or any needed repairs. Maintaining a wide air-gap that remains free of debris alleviates that issue.
Yeah I'd like to keep it far away but where the decking meets the building has to look somewhat finished and not a super big gap.
It sounds like I would just forego any type of hard bent metal flashing at the wall to deck area and just let air and water flow between the deck framing and the siding with a sufficient air gap. Yeah?
Thanks for your help!
Nick
I leave more like an inch to inch and half gap between house and deck framing in these situations and cover the gap with the decking leaving a 3/8 to 1/4 gap there. No flashing.
I say you want a gap but it should be about the size of the gaps in the deck boards. The framing could be set back an inch or 2 but the finished surface close enough that important items can’t fall into an inaccessible hole and lost forever. Yes that part of the home will need to be water tight and finished before the deck is built.
Modern codes make it all but impossible to build a new deck on an existing home that is not free standing.
Walta