I’m building a new deck and I plan to space the ledgers off the siding so air can circulate. My question is how much is enough — are 1/4″ spacers ok?
Thanks
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The only problem with 1/4" spacing is that it can get clogged up with debris. I like closer to 1/2".
Beat it to fit / Paint it to match
Good point - I'll go for a bigger spacing.
Thanks
I seldom build decks anymore. Years ago, folks nailed the ledger directly to the house, no flashing. I did many repair jobs that usually included replacing the box sill and calling the exterminator. Many started using flashing but then they would nail the decking through the flashing, this wasn't much better. If enough of the flashing was exposed, owners managed to cut it with a snow shovel. I started to use spacers and let the siding do the job it's supposed to do. If you place sona tubes next to the house as a support for the free standing deck, there can be some issues. If your roof spills water, no gutters, the accumulation of water can freeze and lift the tubes. This is in cold climates. Another thing to consider is the perimeter drains that are present on newer construction. If there isn't sufficient depth of fill, you could end up boring a hole through the drains. Digging for sona tubes can be quite a chore depending on type of soil. In my area, bowling ball size rocks are too common. You can end up with a sizable excavation just for a tube. Always call Dig Safe or whatever your local service is called unless you were there when the foundation was dug and positively know if anything is underground.Some/most think I'm nuts. I use heavy plastic 1/2" pipe couplings for spacers and run the bolts through them. I can put a dowel in them and cut an angle with my miter saw to match the siding. Some use double nuts and washers between the ledger and the siding. The important part, besides a solid connection, is not to trap water. The next time you stop at a gas station on the Interstate, look at how those giant signs are mounted on the bottom. If the wind doesn't bend those four bolts, I'm not too worried about a party bending dozens. The worst that can happen is bending the bolts but 20 yr. old decks, that I built, haven't bent yet. Maybe the parties are too tame.
Beat it to fit / Paint it to match
Check out issue 172 (July 2005) for a good deck framing article. I used the PT ply spacer and double rim joist method he shows here, and thought it came out great. It is only a little bit more work, but the detailing is really good. I'd cut out your T-111 and sneak some flashing under the building wrap. The only thing I might do differently from the article is let the rim joist that is next to the house sit 1/4" lower than the one the joist hangers will hang on. This gives plenty of room for the flashing to shed water without the water being hung up on the first deck board.-Rich
If you're putting the ledger against the siding, how are you going to flash the ledger?
I was going to space the ledger off the siding (which is T-111) so that it wouldn't (I think) need flashing so that air could circulate between the siding and the ledger. I was planning on using pressure treated lumber for the ledger.
Thanks
In my opinion, a big advantage of a flashing is that it prevents anything from getting in between the house and the ledger, and keeping it wet in there and encouraging water problems (rotting the siding, water migrating into the bolt holes and into the framing). A flashing can't really be installed nicely if the siding is not cut out of the way to allow the flashing up behind the felt or housewrap. If you are going to omit the flashing I would keep a large space between the ledger and the siding, and I would hold the decking away too, so that you can occasionally clean behind the ledger (probably with a hose stream).
If I cut away the siding, installed the ledger and flashed it then doesn't water accumulate on top of the ledger. Am I being really dumb? -- also please explain how the joists resting on the ledger don't contact the siding etc. And forgive me if I'm missing something really obvious -- I'm just not sure how the details work out this way.
Thanks
Either way work well.
Some guys prefer direct bolted with flashing tucked op behind housewrap.
Some prefer spacing.
I've done both and prefer spacing, sometime difficult to get the flashing up under the siding and a nail or errant staples can drive you nuts!
Inside corners are hell too.
A big box of thick HD galv. Washers and some good polyurethane caulk on your holes and your in business.
On new construction there should be no reason not to properly flash and bolt a ledger directly.
It is definitely easier if it's either new construction, or you strip enough siding to do the flashing. Doing a surgical insertion is not much fun.
Joel, the detail I use is with the joists in joist hangers hung on the ledger. Top of joists flush with top of ledger. Yes, it requires hangers, but this detail means that you can bolt the ledger to the rim joist and the deck is approximately the same height as the interior floor. When you install the joists in the hangers you leave some air space between the end of the joist and the ledger, and then you have the flashing made so that it comes out a couple of inches over the ends of the joists.
A way to avoid this whole thing is to make the deck freestanding, by installing some piers and a girder near the house. In some ways that's the best detail by a long shot, since there is no connection to the house to rot out. For low decks it's an easy detail, for taller decks it's not.