Joist Spacing for composite decking
I am getting ready to add 2 new decks to my house using some sort of composite decking. I’ve gone to the websites of several brands (Boardwalk, Trex, EverGrain, ChoiceDeck, TimberTech, Nexwood, Eon, EZDeck, and others) to determine waht the best joist spacing is. Unfortunately, I sense that most brands are waffling. they seem to recommend between 16-24 inches fro residential construction, but reduce this to 12-16 inches for commercial construction.
It seems to me that, regardless of whether it’s residential or commercial, the “firmness” or “springiness” of the deck will be the same…..so, does anyone have any experiece with joist spacing using these products so that underfoot, the deck feels solid like solid lumber…….any and all comments welcome.
Thanks
Replies
First, check your local building codes.
That being said, do not go with 24... too much span, IMHO, to do what you want. It will be very "springy"... even if the product may support he 24's (never tried 24s myself, though)
I have done 16s. Worked fine for trex. Customer loves it (just invited me over for a "deck warming" party)
Of course, if you are so inclined and don't mind a little extra work and expensse... 12s would obviously be the best.
What it boils down to... I can not think of very many reasons not to go with the narrowest spacing possible.
Of course, all of this is subject to the design of the deck. (how's that for CYA?)
Cam,
16" OC would be the best choice. I've used Fiberon and Trex and like both for what they are in the end.....no maintenance. Cost for the synth board is twice, but the durability is there. Use PT joists and such according to your local bldg specs. Flash against the house. And think of using a biscuit joiner and connectors for your deck surface install....no surface screws or nails!!!
If you want wood, look at Ipe, rainforest tree farm stuff, great patina once weathered.
Mark
>>biscuit joiner and connectors for your deck surface install<<
What rot/bug resistant material would the biscuits be made of? Just curiousMatt
Heavy duty Plastic....believe me they work! It's a sharp look of no visible fasteners on the deck surface!!! It's worth the time if you want the look!!-Mark
19.2 o/c for 2x6 trex actually.. to help with the layout have a look at your tape the small diamonds are the 19.2 o/c's ...
...( I know, but some that don't use I joists may not know that one).
(edited..oops)
Alter Eagle Construction & Design | Decks-ca.com | kingofcrown.com
Edited 8/3/2004 11:59 am ET by Altereagle
19.2
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming.... WOW!!! What a Ride!
19.2 " oc = 5 spaces in 96"
16" oc= 6 spaces in 96"
24" oc = 4 spaces in 96"
Thanks Hube....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming.... WOW!!! What a Ride!
yeah i would like an answer to this question too.
The contractor I work for uses 2x8's on 16" centers and we put a stem wall under the deck if its more than 8 ft. out from the house. I'm currently involved in a 3600 sq.ft. home with full length decks front and back. We are using some synthetic product like Trex, but thats not the brand. I love those new deck screws with the self cleaning heads and coarse threads up high on the shank. What a dream compared to the old boogers! Just as an aside, the homeowner picked his own architect, and as a result our prints came in 3/16 to the inch scale (no written dimensions for the inside walls, either) and the house is 73 ft long. I guess having worked with a designer who is a carpenter and designs like one in the past has me spoiled.
Do not ever go with 24 oc, the decking will will develop a permanent sag in high traffic areas. You can also double up joists in high traffic areas to avoid 12oc. We use 2x10s on any span over 8', this seems to help with the springy feel of composites. The only way we have been able to make a composite deck feel solid is to way over frame it.
I have built two decks during the past three years with Trex. In both cases I used the 5/4 material, which by the way has been decreased to slightly thicker than an inch during the past year. I mention this because if you are unlucky like I was to purchase Trex during their dimention change, you can see and feel the height difference between the thicker and thiner boards.....both advertised as 5/4.
I used 16 inch spacing and am very happy with both decks. I tried both 20 inch and 24 inch spacing and both are highly unsatisfactory. I consider 16 inches to be a max span, and for a really firm feel, 12 inches is better. Trex now also makes a material which is closer to 1-1/4 thickness which is supposed to span 24 inches, but I would question that, especially if your deck can hit surface temps above 100 degrees.
Trex/ Composite joist spacing
Frame your joists at 16" on center and for staircases go 12" oc.
Do ya realize you answered a post from 2004?
Please, FineHomebuilding Magazine, UPDATE or DELETE THIS FORUN THREAD. EVERYTHING in this “discussion is AT LEAST FIFTEEN (15) YEARS OBSOLETE. Nothing said was untrue way back at the turn of the century but that was a long time ago. Get current!