Pex-Aluminum-Pex ?'s

[custom1]

If you used Pex-Aluminum-Pex instead of Pex-A, Pex-B, or Pex-C, can you tell me some reasons you went that way. What are some of the positives and negatives? Would you use it again?

I am leaning toward it for the following reasons:

Easy to work with, from what I've read it stays where you put it as you unroll it. Is this true?

100% O2 barrier instead of just meeting some standard. (DIN 4726 is a German Standard. This standard says that no more than .1 milligrams of oxygen will enter a system per liter of water in the system per day. )

Maybe better heat transfer because of the metal.

I found it for not much more $ than regular Pex-A, B or C at a few places online including this place http://www.blueridgecompany.com/ Anyone deal with this company?

I know one negative is: It is bigger than regular Pex, so you need different size compression fittings.

Comments?
Thanks in advance, John

 

[walrus]

I've used it but not in a radiant application. My understanding is it has better heat transfer characteristics. It bends like soft copper, not sure if thats a good thing when rolling it out or not? The fittings I used were compression fittings and I believe they are quite expensive. I've been leaning toward using it for a radiant slab I plan to pour this spring .

 

[custom1]

Thanks for the input walrus.

One other positive is less longitudinal thermal expansion. I know... It's in cement. Where's it going to go.

I thought for sure someone had used it.

Anyone?

 

[CARLOONEY66]

I was a first time user of the Pex-al-Pex and found it quite easy to work with once you get the hang of it. It is nice that it takes a bend like copper and is difficult to kink. I would highly recomend getting or making an unspooler and I used some clips that snap on 6x6 mesh to hold the tube. I found a 10" sheave was helpfull to use for bending the tubing. It was more damage resistant during the pour as well. When you get 3-4 guys in pouring the conrete it will get trampled pretty good. Make sure your concrete guy pulls the mesh up into the slab as it is poured. We did a 6" floor with a area dug out to yield a 10" thickness for later mounting of a twin post lift.

 

[custom1]

Thanks for the info and welcome.

Looks like a nice neat install. How many feet of pex did you use?

I had visions of myself and a helper just rolling it along my pattern. Maybe not. Never did it before.

I think I can make an unspooler. Looks like a plywood base and some way to allow the roll to spin. How much would you say a 1000' roll weighs? I am planning on four loops of about 240' each.

I am also using 6" mesh. Where did you get the clips?

John

 

[CARLOONEY66]

It is split into 7 zones almost 1800ft of tubing.

I bought the 1000' rolls and they are a handfull as far as the weight let alone unspooling them. I laid the tubing by myself but if you bought smaller rolls might be managable. The Wirsbo unspooler has an arm that the tubing passes thru as it comes off the reel and works to straighten the tubing.

Clips can be purchased here : http://www.shop.insulationmaterials...A1149DB6813985E770.qscstrfrnt02?productId=122

I have a ton of clips left over - if you are interested please PM me as I could make you a great deal on them. With the Pex-Al-pex you dont need as many clips as with regular pex.

 

[walrus]

They make clips to hold it to the screen? nylon wire ties is what I've seen used, not sure which is cheaper.
I'm going to use 300 ft coils

 

[custom1]

I'll send you a PM. I already have a bunch of zip ties that I bought CHEAP at HF, but you never know.

 

[Possum]

Looking at using this myself. Any new installations or info out there?

 

[walrus]

I've got 4 300 ft spools in my garage, need to get the insulation down and rebar down and then I'll tell you how the pex al pex went down

 

[custom1]

I ended up not getting the pex-al. Went with the pex-b. I can't remember the reasons why I went that way. I know the price adjusted up while I was procrastinating. Pex-al doesn't tolerate freezing as well.(Though I don't plan on letting that happen) I guess it was the price and I just got tired of thinking about it and just got up one day and called in the order.

I did order thru Blueridge and am happy with their service. They offer a free tubing layout if you order there, but their program only does a back and forth pattern and I am planing 4 inverted spirals(one in each corner). I have my insulation in, but I still need to get the mesh and tubing down.

 

[tdkkart]

I am planing 4 inverted spirals(one in each corner). I have my insulation in, but I still need to get the mesh and tubing down.

I did the spirals in my system that I laid out this spring, just seems to make more sense.
Unfortunately I don't know if I'll be able to find out how it works this winter as I still need insulate and sheet the interior of my building, but my wife is about to get laid off so the money may not be there to finish the project this year.

 

[Possum]

Thanks for the feedback guys. I found pex-al-pex for about the same price as regular pex so I am guessing that usually its more $$?

Also, in regards to layout - someone here mentioned a program called "loopCAD". I downloaded a free trial and it is awesome to use.

 

[Possum]

I ordered 900' of 3/4" Pex-al-pex today so I will soon find out how it works!

LoopCAD layout attached.

 

[walrus]

Here's a pic of some pex al pex installed in my slab. You can see the areas I left clear for a future lift

 

[Possum]

So how did it go down? What size and spacing did you use?

 

[walrus]

So how did it go down? What size and spacing did you use?

I used 1/2 inch, tried to stay about 12 inch spacing but I had to move it around a bit to try and keep my 4 runs as close to the same length as possible. My understanding is 10% is the most you can be off and still have equal flow thru the runs.?

It went down easier than I though, I used rebar ties(bag ties) to tie it down. 300 ft rolls made it easy to manage, I did 2 rolls by myself in a few hours. The kid helped me on the last 2.

I also had a diagram done by a cad system so I knew what way to lay it out. The 2 spaces I left vacant kind of screwed it up but.....

 

[Dragster Racer]

You can get too pickey when you are laying it. You are transfering heat to a big heat sink, so being precise is not needed. I used plastic staples with a staplier I borrorwed from my plumber, and it made things easier. The stapler kept jamming though. I had a plan, but it wasn't very well suited to my setup. So we ran by the seat of our pants, and it worked out fine. You quickly learn the best ways to use up a little tubing before heading back. If you end up with a little more space in an area, like by a wall, than you like, and want to transfer a little more heat there, just do a squiggle along that line. Remember that the heat transfer in an area is related to the amount of tubing there. I would say that the hardest part of the job is unrolling the 250' spools without making a mess of them. Just a bit awkward.

 

[Possum]

Thanks for the info guys!

 

[Possum]

Well 900' (3 x 300') down today finally after rebar yesterday...

All I can say it 3/4 pex-al-pex is pretty strong stuff. It takes a bit to bend and stays bent. I used Weil-McLain AlumiPEX. All in all it went pretty well. And yes, the loop layout does get modified on the fly.

Walrus- did you leave the steel rebar ties on the tubing for the pour? I was going to use zip ties but didn't get any and ended up using rebar ties instead. Just wondering if its okay to leave them? Thanks.

 

[walrus]

Well 900' (3 x 300') down today finally after rebar yesterday...

All I can say it 3/4 pex-al-pex is pretty strong stuff. It takes a bit to bend and stays bent. I used Weil-McLain AlumiPEX. All in all it went pretty well. And yes, the loop layout does get modified on the fly.

Walrus- did you leave the steel rebar ties on the tubing for the pour? I was going to use zip ties but didn't get any and ended up using rebar ties instead. Just wondering if its okay to leave them? Thanks.

I left them, the pex will(could) float otherwise, just bend the ends down so they aren't high enough to screw up the surface