Trex question


  #1  
Old 09-07-04, 02:35 PM
pdelucia
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Trex question

Hello,

I have an old desk made from pressure treated lumber. I want to rip off the railing and steps and re-built it (not the railings, just the steps and the floor) using trex. However, I originally thought that since the original supports on 16" on center and that trex needs center to be 12" that I could just put the trex right on top of my existing pressure treated floor. Is that ok?

Thank you,
Peter.
 
  #2  
Old 09-07-04, 04:23 PM
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Most composite decking is 16" OC, not sure where you got the 12 from. And its not a good idea to go over the existing PT decking.
 
  #3  
Old 09-07-04, 05:37 PM
Homebuilt44
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Trex Question

I have used trex a lot and not by choice remember when you use trex it will sun bleach no matter what you do to it. Now on to your question trex is unique it does require a 12" on center joist work. If you do not follow the 12" recomendation you will find that in hot climates it will sag badly between joist.

As for decking over the old deck NO WAY you will cause rot of the old deck and mold. Its not a good thing to smell when your grilling.

I suggest you check into E board decking (or of that type)it has a better installation time and dosen't kill saw blades as fast. It also looks better than trex and it will install on 16" centers. It is a little more expensive than trex but in my opinion it looks a lot better and is more durable.

E borad is exactly what its called it looks like a E points down

Hope it helps
 
  #4  
Old 09-08-04, 05:15 PM
pdelucia
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Thank you. I will definitely check out E board. Is there a site online? I'll search around..

Thanks again!
Peter.
 
  #5  
Old 09-08-04, 07:18 PM
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Homebuilt44,

Where are you coming from? 2X6 Trex needs joists set at 20" O.C. 5/4 Trex needs joists set at 16" O.C.

pdelucia,

No matter which composite you use, follow the mfgr's recommendations for joist spacing. MOST are 16" O.C., but there are exceptions.
 
  #6  
Old 09-09-04, 10:28 AM
pdelucia
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Thanks. I just don't want to have to add footings when I rip up my current deck (floor, walls and steps). If that is all pressure treated lumber, that should still be ok, no? (If I replace everything except the supports?

Thank you,
Peter.
 
  #7  
Old 09-11-04, 03:08 PM
Homebuilt44
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Lefty

When I use trex here in florida the hot sun causes a bad sag in it if you dont use 12" centers on 5/4 people here love it but it sags bad from the heat.

Thanks for asking

I also have one1 deck in court right now because I followed the homeowners wishes and put in 16"o.c. joist. Go figure! I did what they asked and I kenw better. LOL
 
  #8  
Old 09-11-04, 03:33 PM
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Homebuilt44,

I don't use 5/4 Trex, I use the 2X6, and I put the joists at 20" or less. Have never had a problem with sag, and trust me, Redding is a WHOLE lot hotter than Florida. (We usually compete with Death Valley for being the hottest place in the U.S., and occasionally, we win!!) Virtually every day from early June to early Sept. is triple digits, and most are above 110.

pdelucia,

As long as your present beams are properly supported by your present posts, adding extra joists on top of the beams won't result in you having to add more footings and posts. As to the CONDITION of your posts, beams, joists, etc., that is something you will have to look at when you get the decking removed. Just because it's P.T. doesn't mean you won't find rot.
 
  #9  
Old 09-13-04, 10:09 AM
pdelucia
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Hmm.. Thanks for reponding.. I am in Central New Jersey.
Not too hot.. can be very humid though.

So, just do I understand,
If I use 2x6 trex, I would get away with 16" OC.
If use 5/4 trex, I might be able to get away with 16" OC. 12" would be better.
I cannot/shouldnot put it over my existing P.T. desk..
I should replace my existing P.T. posts?

Thanks,
Peter.
 
  #10  
Old 09-13-04, 11:04 AM
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pdelucia,

1. Humidity won't bother Trex, or any other composite. Heat would be what makes them subject to sag if they aren't properly supported.

2. 2X6 Trex can span joists that are 20" O.C., but 16" would be better. 5/4 Trex can span joists that are 16" O.C., but 12" would be better. The shorter the spacing between the joists, the more solid the deck will feel when you walk on it (no 'bounce'), and 'sag' of the decking becomes a non-issue.

3. Don't install the decking over your present decking. Remove all of that and put the new decking directly on the joists.

4. Once you get the old decking off you will be able to determine the condition of your current substructure -- the joists, the beams, the posts, etc.If you find rot, replace the necessary pieces to get rid of it. You could be replacing nothing, parts, or everything. You won't know until you get it exposed.
 
  #11  
Old 09-14-04, 05:14 AM
pdelucia
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Hello,

This is perfect. Thank you!

Peter.
 
 

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