Deck building sin #798 – trapped water and rot.
I have seen too many cases where decking as rotted at end joints where two pieces join over a joist. Even seen it on PT decking. Also where trim pieces have been put over the rim joints and top flush with the decking.
With my new deck I have designed out all of the points.
But I am wondering about the way that I want to do the railing.
I want a simple, plan railing systems. 2×4 on flat for top rail. Vertical 2×4 for a top sub-rail. And another for a bottom rail.
And Deckorators for spindles.
The corner post will be 6×6 PT support post continuing through the deck. The top will be beveled 1″. Intermediate post will be 4×4 cedar.
I want them to all be cut to the same level and the top railing goes over the top. That means that there will be a splice at each post.
Now I plan to seal all of the cuts, both the rails and the post, with Termin8, a water repellant/protectant.
But if this is enough.
My option is to run the post a couple of inches higher and die the rails into the side. But I don’t like that look.
William the Geezer, the sequel to Billy the Kid – Shoe
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William the Geezer, the sequel to Billy the Kid - Shoe
I don't like the exposed end grain on the posts that you get with 6 x 6's and 2 X 4 top rails. I've done the same thing and used 2 X 6" for top rails which covers the 6 x 6 but still leaves joints over the posts. Trying to miter the corners always leaves a nasty triangular gap when the top rail shrinks. I did a deck last year with that detail and made Ipe caps glued down with Marine 5200 to go over all the splices but the more often I look at it the less I like it although the customer loves it. and I've left the post proud too but don't care much for that look either.
Maybe I'll just go with barbed wire next time.
That is why I want to but a 1" bevel on the 6x6 to bring it down to 3 1/2" surface on the top. Will still look a little strange. But I think better than just cutting it flat..
William the Geezer, the sequel to Billy the Kid - Shoe
Laying in bed this morning I realized that I have an inside corner on the deck and it line up with the 2 outside corners that it joins. Also 3 of the post might have to be longer than 16 ft'rs to go over the top. I need to check the slope of the yard to be sure.I have decided to ofset all the support post to one joist bay over.Then all of the railing posts would be 4x4 cedar. Actually that is what I wanted to do in the first place, but wanted the solid connection with the joist notched into the post and not just sitting on top using a post connector. Also I did not want the metal showing..
William the Geezer, the sequel to Billy the Kid - Shoe
There you go. I like that look a lot better and think it will be just as strong.
if you need some 2x2 composite ballusters, black, let me know. I have a LOT of them. about 1100 8-footers.
I refuse to accept that there are limitations to what we can accomplish. Pete Draganic
Take life as a test and shoot for a better score each day. Matt Garcia
Thanks, but that is not the look that I am going far..
William the Geezer, the sequel to Billy the Kid - Shoe
Bill, try this:
Run the 6x6 support posts an inch and a half longer, fabricate some 7x7 post caps outta some 2x8 stock with four half-thickness 45º bevels (you know the drill); then run the 2x4 handrails into the sides of the posts tucking underneath the overhang of the post caps.
You can get as fancy as you like with those caps: bead the edges; run a core-box bit around them; bevel like I said above and add one or two upper cap(s) made the same way but each an inch smaller than the one below it so it overhangs sort of pagoda-style....
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
That would be a nice look.But in a later post I decided to offset the suport posts from the corners and cut them flush with the deck and have separate 4x4 posts at the corners and also between.The idea is that I clean look with the top rails "continous" (nothing above it). But that leaves open splices in the top rail over the posts.But I am going to put a bevel on the top plate. I will cut some squares out of 6x2 stock and put the same bevel on it and set on top the post to see if I like that look. If so them I can mount the rails into the side of the post like you suggested.From a construction point I think that would be a GREAT improvement over what I want to do. Just not sure if I will like the look..
William the Geezer, the sequel to Billy the Kid - Shoe
Post some pix when you're done.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I had all of the railing pieces rough cut and stained and about 1/2 the decking down before the surgery. But ran out of time.
The frame was built by a BTer, CJ Youngkin ( bayendeavors ).
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And I had a friend finish up the decking and installing the rails.
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William the Geezer, the sequel to Billy the Kid - Shoe
For some reason it I was only able to embed the first 2 in one message.
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You might notice that the caps don't show in some of the pic. I just set them in place. As I feel like it I will screw them down.
I also need to add more screws to the decking (just 3 each), but I will have use more force to tweak the boards. So that will have to wait a couple of months.
And stain the frame and decking next year..
William the Geezer, the sequel to Billy the Kid - Shoe
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The last just because I thought that the shadows looked neat.
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William the Geezer, the sequel to Billy the Kid - Shoe
Looks great Bill, like it was all thought through. I like how the rails are between the posts as opposed to the flat 2x on top. The bread board ends of the decking are a nice touch also.
I don't like the looks of cut ends of decking.And I have learned that the common practice of adding a skirt board to extend over the ends forms a water trap where the decking ends rot out.
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William the Geezer, the sequel to Billy the Kid - Shoe
Very nice, Bill. I like the colours you chose, too.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Bill ,
you mention cutting the 6x6 flush with the deck, I think you'd be better off setting the post so it's under the corner, then don't notch the post for the joist, just connect with carriage bolts through both (post and joist), much less chance for rot, and far stronger connection than notching.
As for the railing, Dino already mentioned my idea, or you could do a half lap joint at the corners instead of a miter, a little more fussin' but no joint to open up due to shrinkage, or at least not as much, if that look is OK....not sure...... just my 2cents.....
Geoff
Bolt the post to the beam is not enough in the newer codes.The beam needs to be setting on the post.Either notch out the post. Or cut the post off flush with the bottom of the beam and use a post connector.And I don't want the looks of the post connector for this application.And I am not as concerned about rot in PT SYP. But the cut will be sealed.The 1/2 lap would be a good idea, but since I am profiling the top of the top rail it would have to have a mitered 1/2 lap. And I don't want to be fuzzing with it. I will have a tight time frame and want to prefinish the railings. So I think that I will have the rails put into the post and put on the cap that I mentioned..
William the Geezer, the sequel to Billy the Kid - Shoe
Bill,
I think I was not clear enough about the notching....... you should not notch the joist into the post and then have the post continue up and become the hand rail post, as was what you indicated you were thinking of doing....that creates a weak spot for the hand rail post, the post should be notched to the outside so as to maintain structural integrity for the hand rail system, there then needs to be thru bolts installed at that post/joist notch connection to have it meet code required impact loads (200 #'s applied laterally against the post).
Bolt the post to the beam is not enough in the newer codes....The beam needs to be setting on the post.
I'm not aware of any requirements to have the beam sit on the post, or any restrictions on a thru bolting connection
And I am not as concerned about rot in PT SYP...... But the cut will be sealed.
But you mentioned your concerns of rot in the first line of your post.
The 1/2 lap would be a good idea, but since I am profiling the top of the top rail it would have to have a mitered 1/2 lap.
Well, that depends on the type of profile you're going to do....if it's not to complex you can do the 1/2 lap joint then profile after assembly......that way you can router both sides of the inside corners at the same time, using a guided bit. I'm assuming something like a round-over bit or such. The outside edges are obviously straight forward.
Geoff
Having the post continue up to be the railing post at the corners was my first though.But you would still have enough meat on a 6x6 to safely support the railing.But I have for many reasons I have decided against that. One of which is I did some figuring and by moving the post in and cantilevering the two ends I can get by with just the 2 post. And the main section the 3rd post would have be a distraction from inside the house looking at the lake.I am basing the structural design on Prescriptice Residential Woood Deck Construction Guide", based on the 2006 IRC, by the American Wood Council.Now things like this are typically only cover the most common applications. But it indicates that just bolting the post to the beam is not acceptable. But that does not mean that it is in all applications. I have not tried to research the actual code.The profile is a double bevel put on by running it through a table saw..
William the Geezer, the sequel to Billy the Kid - Shoe
Nice work Bill. Looks like a nice location too.
I'm about to grapple with this issue, having built the deck and fiberglassed it a few years ago, now it's time for posts and railings.
I see you put your posts inside the rim joist. Is there anything to resist rot between the post and joist?
I'd like to avoid the classic problem of rotten joists.
Scott.
Well I saw your location and you had different lumber and weather than we do.We have PT SYP and the PT does a good job penetrating deeply into the SYP.So I don't have the problem that you do.You might want to look at this article."Don't Build Decks That Rot"
http://www.deckmagazine.com/abstract/16.htmlIt was written by a deck builder in the NW.But I treated the notches with a paintable water repellant, protectant. That adds a little more anti rot and the water repellant help keeps the water was absorbing into the end grain. I used Jasco Termin8. They have seveal other produces and IIRC Woodlife also has similar prodcuts.Also the seat cut is fairly tight to the joist limiting the amount of water that can get in. And if a little does you have the whole lenght of the post to dissipate the moisture..
William the Geezer, the sequel to Billy the Kid - Shoe
Looks nice Bill!
>>>"Don't Build Decks That Rot"Fantastic. Thanks.Scott.