I got an estimate on a deck at a new lumberyard the other day. They specd 5/4 decking over 2 by 10 joists spaced 24″ O.C. is this spacing adequate for 5/4 decking? Ive always spaced at 16″. Cost savings is tempting but dont want “spongy” deck. Input is appreciated
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Don't do it. 24" cneters won't work out well in the long run.
I wouldn't do it, but I suppose if you were using mahogony as a deck surface you might be able to get away with it.
I just did a big deck in mahog, but went 16' OC. Very solid.
Jake Gulick
[email protected]
CarriageHouse Design
Black Rock, CT
Ditto to the above. 16" o.c. for 5/4 decking.
Thanks to all. Kind of thought so. Guess just wishfull thinkin. (Babies need shoes!)
Good Day All :)
It would depend on the decking but I would go 16" unless it is a composit like Trex, then I would go 12". 5/4" Ironwood would span 24" with no problem.
The cost savings is not in the framing but in the decking material.
For instance it would cost you more to frame at 24" with 2x4 decking than........
12"o.c. with 1x4 decking.
"Rather be a hammer than a nail"
Bob
You don't say how long the joist are or what the deck lumber is. Ipe - as Bob has mentioned, will have no problem with spanning a 24" openning but if the joists ar 14' long, they would have a hard time handling things. Ipe' is a heavy lumber.
Excellence is its own reward!
All material specd cca (Cheap, Crooked, Awful).
joists will span 11'6"
Double 2x12 beam spans appx 7' center to center over 4x posts
Hope this helps
Didn't know you could still buy CCA for residential.
But I wouldn't use it for a deck, especialy with 24" open. It might pass code in southern climates with no snow load - minimally - but it should only take one or two more joists to beef it all up firm..
Excellence is its own reward!
Plenty of CCA around here....Matt
Yes, CCA is available until the end of the year.
Don't know if that is the cut off date for selling or producing it.
I was asking about that the other day at the board store, they said that they would not receive any more CCA after the end of the year, but would be able to continue to sell their stock until it is gone.View Image
already gone here..
Excellence is its own reward!
36258.14 in reply to 36258.9
"Yes, CCA is available until the end of the year.
Don't know if that is the cut off date for selling or producing it. "
What will replace it??Jake Gulick
[email protected]
CarriageHouse Design
Black Rock, CT
There are a couple of other forumlas. I think that one of them is ACQ. AFAIK all of them are copper based.
From what I have read the new versions are all much more corrosive and only hot dipped galvanized or stainsteel hardware should be used.
Isn't that just ducky, now we get to spend more on all our joist hangers and Teco nails. Take this out, put this in.......
Reminds me of Leaded gas........
First we pay to put the lead in then we pay more to take it out.
I was thinking it might just be easier to tell the kids to quit chewing on the playground equipment.......but we all know that isn't really the issue. It is the fact that the arsenic is leaching into the soil and water........"Rather be a hammer than a nail"
Bob
It was just a couple of weeks ago that I read an article saying that after two years of studies and unrelenting pressure from the environmental lobby, the center For Disease control has concluded that using CCA in playground equipment posses NO SIGNIFICANT RISK for children playing there. It agreed with industry scientists that the risk is similar to eating plain old dirt. I don't know if everyone is aware or not, but arsenic is a naturally occuring element in most soils, more abundant in some than in others..
Excellence is its own reward!
Agreed- Arsenic is a chemical element that occurs naturally in rocks,soil,water,air,plants and animals.I think it is time to start a new post on The "CCA story""Rather be a hammer than a nail"
Bob
It looks like the right approach might be to buy a lifetime supply of everything that actually works before the enviros get it banned.... ;-)
-- J.S.
Just want to correct one mis-assumption: the reason it cost more to "take lead out of gas" was that the tetraethyl lead additive improved the octane of crappy gasoline. Without it, they had to make better gas- and that cost more money. Good thing they stopped, though- there was plenty of evidence that lead from gasoline was ending up in people's bodies and lowering the IQ of their kids (amongst other health problems). Some people think that Rome fell because the ruling classes had indoor plumbing- plumbus being Latin for lead...
On the CCA question- I personally doubt there's much of a hazard to ordinary uses of CCA lumber- though I'd be concerned if I installed it for a living. From what I've seen of the toxicology, both the chromate and the arsenate are bigger problems on inhallation than on ingestion- not much chance of the homeowner inhaling CCA while sitting on their deck drinking beer, but good risk of YOU breathing a fair bit of it when you're cutting it all day...
In Toronto they tore up the play structures at most of the city's schools because they were worried about CCA-treated wood and other perceived safety risks. Now the kids have nothing to play on, so they sit around, get fat, and are more likely to get diabetes. Unfortunately, the public are reactionary and fearful with respect to "chemicals", and so the public and their institutions don't use their heads when dealing with "chemical"-related scares.
FYI, there's an article in the very next issue of FHB on the corrosiveness of the new PT lumber. My guess is that after you get over the sticker shock from the new lumber, the extra cost of HD or SS fasteners and hangers won't phase you a bit.Andy Engel, The Former Accidental Moderator
Since the thread has gone to treated lumber from joist spacing ......
I was in NYC yesterday and while I was checking out, I spied a gaggle of guys from HILTI. So, being inquisitive, I asked one of the dudes about HILTI concrete to lumber fasteners and the new ACQ treatment.
He knew nothing about it. We went through the catalogue and we could find NOTHING about potential effects.
Lawyers are rubbing their hands in glee.Quality repairs for your home.
Aaron the HandymanVancouver, Canada
"Lawyers are rubbing their hands in glee."
LOL, I first read that as "rubbing their hands in glue" as though the fingers aren't sticky enough.
Sorry to the legal guys out there that deserve respect. I couldn't resist..
Excellence is its own reward!
Splinter,
How big is the deck? I mean the cost difference between 16oc and 24 oc can't be that much. Mahogany, Ipe, and Bubanga even though they can be used on 24oc, 16 oc gives you a better product. The spacing on the joists should be determined by the thickness of the deck. This information is all avaiable online and at any good public library.
Let us not forget the option of cubit spacing if it helps.
;-).
Excellence is its own reward!
This may be a job for "Black Diamond"
Who ever invented work didn't know how to fish....
Who's turn is it to let that cat out?.
Excellence is its own reward!
Have fun... I just got the issue of differently color coded meter stuckes and their assorted markings issue to lay down...
I'm a little tired....
Who ever invented work didn't know how to fish....
"Who's turn is it to let that cat out?"
Cat, Black Diamonds, Black Cats, sounds like Fireworks to me.
Splinter,
I rebuilt my 20 year old deck this summer. The old decking was 2x6 cca that had started looking pretty ratty. We decided to use the 5/4 cca decking with rounded edges, mainly for the appearance. The joists are 2x10's on 16 inch center and I can still feel the difference between the new stuff and the old 2 x 6's. It definitely moves a bit under foot so I can imagine it would really feel flimsy with the joists on 24" centers.
Hope this helps your decision,
Mr Bill