No great newsworthy info here, but I thought it was interesting to see the results of not considering expansion/contraction when using Azek.
This is a garden cart that I built from T-111. The lid is also T-111, but I wanted to add a little rigidity by doubling up around the perimeter. I had some Azek (It could be Koma, but it’s all the same stuff) lying around so I used that.
I didn’t really consider the expansion/contraction issue, nor do I really care, but here you can see the lid has taken a curve due to contraction in the current cold temperature. When the weather warms up, it lies flat again.
As I said, it doesn’t bother me a bit, but it does serve as a reminder (at least to me) to always consider expansion/contraction when using PVC trim.
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It's a PITA but with that limitation its still better than wood. Everything has is negatives but pvc trim has much fewer.
<Everything has is negatives but pvc trim has much fewer.>Okay, it doesn't rot... then what?... I'm trying to go in a positive direction for 2009!http://www.tvwsolar.com
Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
no knot holes
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<no knot holes>Yep, does have some voids, though. The stuff is usually pretty straight, too.I really dislike working with it, especially the "sawdust." I use it where ever I think moisture may hang around for a while, but anything else we use Miratec, never have seen that stuff move.http://www.tvwsolar.com
Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
what kind is Mioratec? Like GP primetrim hardboard? I haven't used it.I dislike Azec for a lot of reasons too. This time of year, it is too brittle to use for exterior trim. you can do it, but very carefully, predrilling and leaving room for expansion....
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Exterior MDF... smooth on one side, grained on the other. I wouldn't use it for column bases, or as trim against brick... but use it almost everywhere else.But, it is MDF, and except for being able to get wet, it behaves just like MDF. Edges can flake, splits when nailed at edge, hard to set nailheads, fine dust from cutting, on the other hand, takes paint exceptionally, doesn't warp, check or cup, no shrinkage or expansion, and way less money than pvc.Is it like primetrim?http://www.tvwsolar.com
I went down to the lobby
To make a small call out.
A pretty dancing girl was there,
And she began to shout,
"Go on back to see the gypsy.
He can move you from the rear,
Drive you from your fear,
Bring you through the mirror.
He did it in Las Vegas,
And he can do it here."
sounds very similar.The guys nicknamed the GP product. "Pus wood" probably because working it without dust masks gets your nose puss-y
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there have been a few stories here of full lengths splitting when it is installed in the heat of summer, then shrinking 1/2" in length when it gets below zero.
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Taunton University of Knowledge FHB Campus at Breaktime.
where ...
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I think its a classic case of BOTH changng. The 'Tijuana elebben' may have got fatter as the azek shunk?
Early humidty measuring devices were 2 thin strips of wood, one cross grain to the other and glued. As the hum. rose the crossgrain swelled and made a straight stick..when it fell, it would shrink and curl the longgrain sliver along with it. I forget the name and inventor ( DaVinci? maybe).
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
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That's possible, but the humidity tends to be lower in winter so the T-111 should be smaller too.
Then again, is humidity really lower in winter? Indoor relative humidity is lower, but I never really thought about the relative humidity outside. The amount of moisture in the air is less, but it's ability to hold moisture is less too, so that probably means that the exterior relative humidity remains similar all year long. And what does that tell us about wood shrinkage?
What about the joint surfaces between the two? Completely water tite?Spheramid Enterprises Architectural Woodworks
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What about the joint surfaces between the two? Completely water tite?
No. They are simply screwed together. What difference would that make?
The underside of the t-111 is wetter than the top and swelled, the azek has not. Any laminating of dissimalar materials , when one moves hydroscopically and one don't creates funny movements.
Plus T-111 is the most warpy damm stuff I have ever seen..the old Fir wasn't as bad as the SYP we mostly see today.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
Here in NorCal, we don't have to deal with temps below freezing too often (maybe 20 days per year) but I have yet to see any trouble with Azek, despite temps up to 110 dergrees. That said, when we installed Azek, we firmly screwed off every single joint (butts, laps, whatever...).
It holds, still.
Don't know how you people deal with all of that cold weather...or high temp will be 45 and I am freezing to death...lol, what a sissy...
I'm with sphere i don't think it's the azek as much as the t-111 pulling the azek
It may well be a combination.
As an experiment, I cut a piece of wood and a piece of Azek to exactly the same length (about 3') in my 65° basement. Then I place them both outside where it was about 35°. After a few hours, I compared them to each other. The Azek was just about 1/16" shorter.
Allowing them to both warm up in the house results in them both becoming the same length again.
So, Azek shrinkage is real. I don't know how much this expansion/contraction can be resisted when PVC trim is secured in place, but it's still something that needs to be considered.
thats good to know
I think some of us are getting confused. The expansion/contraction is due to temperature not moisture.
We've been working with wood and it's moisture issues for so long that we are thinking plastic acts like wood ;^)
Yeah but if the 1-11 is wet and swelled, and atached to something that doesn't swell, you get a bow. Add the cold shrink to the Azek and it compounds the issue.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
I agree! The t-111 is picking up moisture from below or loosing it on top.
Some of the posts seemd to be saying moisture was swelling the aztec.
I think I've heard of some plastics picking up moisture and swelling.
It got cold here. Still cold this morning. The wall of this house sure could use some insulation! Freezing!
Edited 1/5/2009 10:17 am ET by popawheelie