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How to terminate ledgerboard flashing?


inspectorreuben
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In the photo below, there was water leaking in to the wall where the deck heights changed. I'm sure that water is running horizontally along the ledgerboard flashing and then dumping in to the wall where the flashing ends. I've found this defect on a lot of decks, but it's usually not this obvious.

Does anyone have any photos or diagrams showing the proper way to terminate the ledgerboard flashing to prevent this from happening?

I've gone through every archived issue of the JLC (only $45 for the DVD), and couldn't find a single article that dealt with this detail.

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tn_20114382433_DSC00844.jpg

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- Reuben

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Hi,

They should have integrated some self-adhering bituthene (ice and water membrane) into the flashings at the transition between the two decks behind the siding. I'd have used coil stock behind the whole thing and spacers like below.

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tn_20114395526_DeckToHouseConnection.jpg

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ONE TEAM - ONE FIGHT!!!

Mike

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Thanks Mike. That's a good drawing, but it raises a question about spacers behind the ledger board.

There is no longer any friction between the board and the wall, so all the weight transfers to the bolts or screws (I call the pointy ones screws [:)]).

Is it not a stronger construction detail to have the ledger board tight to the wall?

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Hi,

They should have integrated some self-adhering bituthene (ice and water membrane) into the flashings at the transition between the two decks behind the siding. I'd have used coil stock behind the whole thing and spacers like below.

Click to Enlarge
tn_20114395526_DeckToHouseConnection.jpg

79.86 KB

ONE TEAM - ONE FIGHT!!!

Mike

I like that idea better, although, the flashing should still have an end dam.

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Hi,

They should have integrated some self-adhering bituthene (ice and water membrane) into the flashings at the transition between the two decks behind the siding. I'd have used coil stock behind the whole thing and spacers like below.

Click to Enlarge
tn_20114395526_DeckToHouseConnection.jpg

79.86 KB

ONE TEAM - ONE FIGHT!!!

Mike

I like that idea better, although, the flashing should still have an end dam.

I will never see end-dam flashing on a deck in my area . . . not that it isn't a good idea.

I see decks flashed like Reuben's all the time and, even when there's no change in heights, water runs between the trim coil--which is overwhelmingly the flashing of choice--and the siding. The secret is having the lower portion of flashing act like drip-edge, as in Mike's drawing. But . . . I can't imagine I'll ever see that, either.

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Thanks for the replies, everyone.

I'd have used coil stock behind the whole thing and spacers like below.

Click to Enlarge
tn_20114395526_DeckToHouseConnection.jpg

79.86 KB

In the August '03 issue of the JLC, they discuss using spacers like you showed above. They basically said this is a practice that should be avoided, but if you're going to do it, use the following fastener schedule:

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tn_20114316459_Fastening%20Schedule%20for%20ledgerboard%20with%20spacers.jpg

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Can you imagine anyone actually doing that?

- Reuben

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Thanks Mike. That's a good drawing, but it raises a question about spacers behind the ledger board.

There is no longer any friction between the board and the wall, so all the weight transfers to the bolts or screws (I call the pointy ones screws [:)]).

Is it not a stronger construction detail to have the ledger board tight to the wall?

Good question. A bolt generally has a much larger diameter than a nail and provides greater shear capacity. I question the contribution of friction in an arrangement where the ledger is nailed tightly in place. It's mostly just the nails versus gravity IMHO.

Marc

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(see diagram) Cut the flashing long, cut at the solid red lines and bend at the dashed line. Use silicone where they overlap at the back.

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tn_20114402717_Flashing.jpg

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l like it. But it would be slightly better to place the blue section in *front* of the grey one. As you've got it now, any water that makes it through the vertical seam is a leak. If you put blue in front of grey, water could only leak through a single point instead of an entire vertical seam.

- Jim Katen, Oregon

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I like metal (copper) for some stuff, but nowadays I rarely use metal for this sort of thing.

40 mil self adhered allows forming the pan in ways you could never get metal to go. It also makes the interior back dam much easier on doors.

You can take a mess of angles and vertices like Reuben's deck, layer it all with 40 mil goo'ed into place, and that thing'll never leak.

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