Building a 20'x14' deck and would like some expert opinions

I searched for a chart, here’s a PDF that may help you.

-- -** You are never to old to set another goal or to dream a new dream ****************** Dick, & Barb Cain, Hibbing, MN. http://www.woodcarvingillustrated.com/gallery/member.php?uid=3627&protype=1

JMG

2×12’s are fine i would like to know how your thinking to fix to the house if your not using posts and is the area under the decking is this open to be seen as i would look at that sort of area as great storage space and if so the post round the edge would be fine also…...

Andy

-- cut it saw it scrap it

some were in the middle of the span ,
i would put a row of blocks ,
under a plank for the 20 ’ run .
to keep the joists from ” flipping ” or twisting under any party weight .
i make a story board , about 6’ long ,and use it to mark my loist tops with ,
checking against a string ocasionaly for straight , as planking is not all even .
and start it out side edge with any overhang you want on decking .
and work back t bldg. last plank against bldg. can be scribed or next size up to fit to bldg.

-- david ,new mexico ,allheart

it will carry easily jon. be sure you get that ledger board good and secure against the house, and also be sure to get everything watertight after you are done ripping off siding and reinstalling.

-- James, Bluffton, IN

Thanks for the reply Andy. I am attaching the deck to the house with 3-3/4” tapcon concrete screws paired with posts on both ends of the deck. The homeowner wants the space underneath the deck for a patio and access to the finished basement.

-- -Jon

James, I wish I was ripping off siding, but I’m attaching to brick. Anyone have any better suggestions than 3-3/4” tapcon concrete screws with posts on each end?

-- -Jon

Dick i just looked at the PDF and wow your building codes are so different over there we still use 4×4’s up to 12’ so i think i will not say to much from now on lol….......

Andy

-- cut it saw it scrap it

Thanks for the tip David, we’re on the same page with the blocking. Do you think one row will be sufficient, or should I go with 2?

-- -Jon

Thanks for the PDF Dick, I agree with Andy, very different from the way we do it here in SC.

-- -Jon

The 12’s are fine for the joists…even a little on the strong side (which is good). For the attachment to the house I would use some expansion bolts (it’s basically a threaded rod, with a wedge on the end, some shims in the middle and a nut on the other end. when you tighten the nut it pulls the wedge into the shims and makes it’s own anchor; these are MUCH stronger than tapcons, which aren’t really structural at all). You’ll want to put two anchors a foot in from each end, and then stagger one every two feet (3 inches from top, 3 inches from bottom etc). To clear span the 20’ on the outer edge you’ll have to use a treated glu-lam beam, at least a 6.75” x 16.5” beam (this is the minimum, number from Boise lumber). One each end you’ll probably want to use 8×8’s with a slight taper two feet from the top, then the top foot plumb again at 6.75”, you can get a special metal connector from USP that is a post to beam in galvanized steel to connect the two. OR you can use 8×10 posts with 6.5” cut out of the top to make a ledge for the beam and through bolt the beam and post with 1/2” carriage bolts. You could get away with 6×6’s and a 3.5” thick mortise and tenon into the beam as long as it is 6” long. To make everything cleaner looking, use hangers on the outside as well and hang the joists from the side of the beam. I would encourage you to place rubber on top of the glulam to help prevent water from sitting there and promoting decay. I’d encourage you to put 1/4” spacers between your ledger board and the brick to let water drain through and not decay the ledger board. If you have any other questions feel free to ask! (I’ve done this for awhile…)

-- Finding satisfaction in creation

with 2×12 , 1 row should do o/k.

-- david ,new mexico ,allheart

Hey Jon
It sounds like you have most of info you need about the only alternative I could think to suggest is depending on what space you have inside the brick wall you could bolt all the way through the wall and have a board inside to have large washers and nuts going through to the outside ledger. In any and all suggestions I would check on your local codes to make sure they conform to your codes.

-- Jim from Heirloom Woodshop Southern Oregon

Wow, thanks for the info ahock. I didn’t have a good feeling about the tapcons anyway. I have convinced the homeowner to let me use 4 posts across the front of the deck instead of spanning 20 ft but good suggestion on the treated lam beam. I was unaware that they were available treated. I’ve used them quite often in subfloors of FROGs . I will be using 6×6 posts on the four corners, 2 more spaced out on the front, and one in the middle of each side.

-- -Jon

Thanks Jim, I definitely need to refresh myself on those codes

-- -Jon

I would also recommend what a1Jim did and bolt clear through the brick if at all possible. That is a long span for just one row of posts. Treated lam beam is a good idea and you could consider a 2 foot cantilever.

-- Those that say it can't be done should not interrupt those who are doing it.

Thanks Jeff, I am considering going through the brick, but I would have to use lags and go into the second floor rim joist, again depending on how much space is between the brick and the frame.

-- -Jon

a word of caution on lagging to the rim joist. make sure it is a structural member and not 1/2” osb as was common for years. Also, if the interior floor system is open web floor trusses, you cannot lag into the ends of them, as the squash blocks will split.

Sounds to me like you would be tap-conning to veneer brick. Bad idea. I once worked for a guy that insisted on tap-conning into the mortar joint because it was the easiest place to drill through. Another bad idea.

If it were a block wall or poured wall fine. But any substantial party weight on that deck away from the house and I would bet you’d pull the whole brick veneer off. Brick veneer is NOT as strong as you would think [laterally]. Go through to the house structure.

-- arborial reconfiguration specialist