# Composite Decking on 24 inch joist spacing?



## Eagle One (Feb 11, 2011)

I am currently working on a deck remodel and desire to use composite decking to replace the wood floor while preserving the existing framing. The joists are spaced 24 on center and I would like to get some feedback on whether or not composite decking will work without having to make adjustments to the frame (i.e. adding more joists). 

Are there certain brands better designed for this? Even with the best style available, am I still risking flexing issues in the future?


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## Nealtw (Jun 22, 2017)

I haven't seen any that will work with more than 16". You only have to move one and add one in a 4 ft space. Depending on age, you may find some joists in tough shape. the trick now is to protect the top of the joists with peel and stick.


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## stick\shift (Mar 23, 2015)

With the current decking removed, I would add a joist in-between each of those you have now.


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## Eagle One (Feb 11, 2011)

Nealtw said:


> . Depending on age, you may find some joists in tough shape. the trick now is to protect the top of the joists with peel and stick.


I see that Home Depot sells this product called Deckwise Joist Tape. 75 ft for almost $30...seems pricey but if I get this I think I would try to cut the 3 inch tape in half and just put it on the very top of the joist rather than wrap around the sides. Some reviews say the sides won't stick well anyway...


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## Nealtw (Jun 22, 2017)

Eagle One said:


> I see that Home Depot sells this product called Deckwise Joist Tape. 75 ft for almost $30...seems pricey but if I get this I think I would try to cut the 3 inch tape in half and just put it on the very top of the joist rather than wrap around the sides. Some reviews say the sides won't stick well anyway...


I would want 2" so it wraps the top. You could get three out of this.
https://www.homedepot.ca/en/home/p.blueskin-weather-barrier-6-inch.1000403475.html


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## ron45 (Feb 25, 2014)

Just my opinion.
Peel and stick is a waste of money and time, when the wood gets that bad why purchase it in the first place.

Have you thought about aluminum decking.
No need to beef up the existing.

http://www.lastdeck.com/images/gallery/Last-Deck Galleries/album/gallery.html


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## Nealtw (Jun 22, 2017)

ron45 said:


> Just my opinion.
> Peel and stick is a waste of money and time, when the wood gets that bad why purchase it in the first place.
> 
> Have you thought about aluminum decking.
> ...


It is not about saving bad wood. it is about saving the good ones and new ones.


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## ront02769 (Nov 28, 2008)

I would forget the peel and stick. But if you don't add a joist between the existing, your deck will have a d between every joist. Ron


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## ron45 (Feb 25, 2014)

Nealtw said:


> It is not about saving bad wood. it is about saving the good ones and new ones.


You took what I said out of context. 
If the wood itself is not going to last that long then don't buy it in the first place.


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## woodworkbykirk (Sep 25, 2011)

ok. back to the question the topic is about..

no you cant span composite over 24" o.c joists.. the product sags when it heats up. you have to do 16" o.c for straight decking and then for herring bone design it has to be 12" oc


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## Nealtw (Jun 22, 2017)

ron45 said:


> You took what I said out of context.
> If the wood itself is not going to last that long then don't buy it in the first place.


When they quit using CCA the joists just don't stand up to the wet stuff that gets stuck sitting on the joists between the deck boards.:vs_cool:


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## ron45 (Feb 25, 2014)

Nealtw said:


> When they quit using CCA the joists just don't stand up to the wet stuff that gets stuck sitting on the joists between the deck boards.:vs_cool:


I haven't found that to be the case here in my neck of the woods.
Only with the ground contact. 

My opinion.
It defeats the purpose 
The gaps left after shrinking of the tread boards is not enough to cause for alarm.
If it is then why purchase the wood in the first place for a deck that is completely subject to the weather.

Looking at your train of thought why not cover the railings.?


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## red92s (Nov 14, 2012)

ron45 said:


> I haven't found that to be the case here in my neck of the woods.
> Only with the ground contact.
> 
> My opinion.
> ...


Taping the joists/beams is not intended to limit periodic exposure to water when it rains. It's intended to limit prolonged contact with moisture and organic material once leaf litter and other detritus builds up between the decking, on top of the joists, and between the plys of multi-ply beams. Railings are a different situation: they don't tend to collect organic trash over time and trap moisture against the wood.


4" rolls of Grace Vycor can be bought for $21. The time and frustration involved with trying to cut it in half to get double the yield out of a 4" roll isn't worth the $50 or so you'd save on an average size deck where you are already spending several thousand dollars. Buy the 4" tape, apply with a head gun to dry lumber, and move on with life.

https://www.amazon.com/Grace-Vycor-...coding=UTF8&psc=1&refRID=YS41VXV9W6S19GA3K246


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## woodworkbykirk (Sep 25, 2011)

red92s said:


> Taping the joists/beams is not intended to limit periodic exposure to water when it rains. It's intended to limit prolonged contact with moisture and organic material once leaf litter and other detritus builds up between the decking, on top of the joists, and between the plys of multi-ply beams. Railings are a different situation: they don't tend to collect organic trash over time and trap moisture against the wood.
> 
> 
> 4" rolls of Grace Vycor can be bought for $21. The time and frustration involved with trying to cut it in half to get double the yield out of a 4" roll isn't worth the $50 or so you'd save on an average size deck where you are already spending several thousand dollars. Buy the 4" tape, apply with a head gun to dry lumber, and move on with life.
> ...


its also to seal the holes from the decking fasteners so water doesnt creep deeper into the joists where the treatment hasnt fully penetrated into


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## ron45 (Feb 25, 2014)

red92s said:


> Taping the joists/beams is not intended to limit periodic exposure to water when it rains. It's intended to limit prolonged contact with moisture and organic material once leaf litter and other detritus builds up between the decking, on top of the joists, and between the plys of multi-ply beams. Railings are a different situation: they don't tend to collect organic trash over time and trap moisture against the wood.
> 
> 
> 4" rolls of Grace Vycor can be bought for $21. The time and frustration involved with trying to cut it in half to get double the yield out of a 4" roll isn't worth the $50 or so you'd save on an average size deck where you are already spending several thousand dollars. Buy the 4" tape, apply with a head gun to dry lumber, and move on with life.
> ...



Just my opinion...

Decks have went 20+ years without any additional treatment at all. You can tell because they turn grey.

When the wood shrinks it also shrinks around screws/nails
When you treat the treads the treatment also covers the exposed joist.
But again, the gap is not enough to worry about.

You have your opinion and I have mine.


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## Nealtw (Jun 22, 2017)

ron45 said:


> Just my opinion...
> 
> Decks have went 20+ years without any additional treatment at all. You can tell because they turn grey.
> 
> ...


Ron, it is about the number of treated joists that have rot in the area just below the gap in the decking. This really shows up in decks built after 2006 when they changed the treatment. This is a cheap fix that may help the deck last that 20 or more years. We first saw tar paper being used for this about 2010 by people who do nothing but decks when they started to get call backs on decks only a few years old.


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## Eagle One (Feb 11, 2011)

FYI - After removing all the deck boards, I have indeed found plenty of trapped organic debris (mostly pine needles) that was causing some staining/minor rot on the top of joists but nothing major.

QUESTION: Instead of this tape, couldn't I just get some good waterproofer/sealer and apply it quickly with a brush to the tops of the joists? Probably cheaper AND faster....?


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## Nealtw (Jun 22, 2017)

Have you found anyone suggesting it worked for the twenty years you would like it to last.


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## Eagle One (Feb 11, 2011)

I will also add that I will only have a few days to 'protect' the joists because the weather is going to turn worse. The tape seems unavailable IN STORE anywhere so ordering online probably won't work. I may have to opt for the sealer by default


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## Eagle One (Feb 11, 2011)

Nealtw said:


> Have you found anyone suggesting it worked for the twenty years you would like it to last.


No, but how long has the tape been around? Do we REALLY know it will last 20 years? I think most of us probably realize that manufacturers embellish their claims (or outright lie) and most of the junk made nowadays is cheaply made overseas and probably designed to last an intermediate time frame so that companies can make their quick profit while the consumer is left with no recourse! 

(Sorry, I am venting a bit here because a new air compressor I bought recently developed a leaky drain valve right after the one year warranty expired! My father's old Craftsman compressor is still running strong after 40 years!!)


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## Nealtw (Jun 22, 2017)

Eagle One said:


> No, but how long has the tape been around? Do we REALLY know it will last 20 years? I think most of us probably realize that manufacturers embellish their claims (or outright lie) and most of the junk made nowadays is cheaply made overseas and probably designed to last an intermediate time frame so that companies can make their quick profit while the consumer is left with no recourse!
> 
> (Sorry, I am venting a bit here because a new air compressor I bought recently developed a leaky drain valve right after the one year warranty expired! My father's old Craftsman compressor is still running strong after 40 years!!)


People in the field were finding this rot on very young decks and started putting tar paper in there. House framers get a supply of peel and stick for windows and always have extra, so they started using peel and stick because they have it.
I put a little Blueskin over a couple holes on the roof of a van and it was still good 8 years later when the truck went down the road. 

The question is how much is your time and troubles and material worth.


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## Nealtw (Jun 22, 2017)

Stuff like this is what has been happening.


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## ron45 (Feb 25, 2014)

Nealtw said:


> Stuff like this is what has been happening.


Not a good example.
In between the treads is just discolored not rotted.

As for the other two spots that is a result of piss poor workmanship/planning, even if paper had been used it still would have happened.


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## Nealtw (Jun 22, 2017)

ron45 said:


> Not a good example.
> In between the treads is just discolored not rotted.
> 
> As for the other two spots that is a result of piss poor workmanship/planning, even if paper had been used it still would have happened.


Besides the workmanship, When water and dirt is trapped, it causes problems.


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## red92s (Nov 14, 2012)

ron45 said:


> Just my opinion...
> 
> Decks have went 20+ years without any additional treatment at all. You can tell because they turn grey.


The longevity of treated framing lumber today is not comparable to what decks were made out of 20+ years ago. I've got no doubt that taping beams and joists may have been an unnecessary expense with the materials available two decades ago. The fact that it wasn't required "back then" doesn't mean much when discussing building projects _today_.


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## Eagle One (Feb 11, 2011)

red92s said:


> The longevity of treated framing lumber today is not comparable to what decks were made out of 20+ years ago. I've got no doubt that taping beams and joists may have been an unnecessary expense with the materials available two decades ago. The fact that it wasn't required "back then" doesn't mean much when discussing building projects _today_.


Are you saying that even treated wood from today is substandard due to poor quality from manufacturers?!!


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## red92s (Nov 14, 2012)

Eagle One said:


> Are you saying that even treated wood from today is substandard due to poor quality from manufacturers?!!


No. It has nothing to do with the declining quality from manufacturers. It has to do with EPA regulations that have been in place since 2004 that banned the production of CCA treated lumber.


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## Eagle One (Feb 11, 2011)

red92s said:


> No. It has nothing to do with the declining quality from manufacturers. It has to do with EPA regulations that have been in place since 2004 that banned the production of CCA treated lumber.


Ah, yes, thanks for clarifying


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