That sounds pretty good to me but maybe someone with more cozy experience could chime in.

It's too bad that we don't have a way to test the R-value of this material. I wonder if there is someone here on BPL that would test a sample?

"The smallest roll you can order is 4' x 25' and $60 which would make you 8 pads....that's just $7.50 per 24" x 74" pad"

- I'd be willing to go into this with a few people. Any takers?

someone needs to test the R value of prodex and reflectix in a backpacking set up ... at the end of the day i doubt you'd save very much

interesting note that the el cheapo MEC blue foamy is actually more efficient than the more expensive evazote ...just less durable ... hmmmm

and the RR solar is da boomba for foooamy efficiency

prodex ...7.78 oz / yd 2 ... assume R value of 1.1 then ... R per oz/yd of 0.14 ... if R of 1.3 then R per oz/yd of 0.17 .... note that i seriously doubt tat a 5 mm thickness gives you anywhere near these R values ... the R values for the blue and yellow mec below are for 1 CM pads, double the thickness of the prodex

the reflectix is listed as 1.25 oz/ ft2 ... so 11.25 oz/ yd 2 ... for an R value of 1.1 if we accept the manuf claim ... which is an R per oz/yd of 0.097

the mec blue standard 9.25 oz / yd if my math is correct ... for an R value of 1.36 .. R per oz/yd of 0.146

the mec yellow standard 13.75 oz / yd if my math is correct ... for an R value of 1.6 .. R per oz/yd of 0.116

the yellow thermalest zlite is 12.93 oz / yd 2 ... for an R value of 2.2 ... giving and R per oz/yd of 0.17

the RR Solar is 17 oz / yd 2 ... for an R value of 3.6 ... giving and R per oz/yd of 0.21

Edited by bearbreeder on 11/18/2010 14:04:25 MST.

Tyson...I'd be in for a pads worth of Prodex and I'd pay double the $7.50/pad cost. I can't place the order because I'm in Canada and Prodex wants $100 to ship a roll here which is insane. I'd pay you $15 + $10 shipping for a 2' x 6' length. $10 should easily cover shipping via the cheapest option (USPS First Class Mail International). If we could get 2-3 more people this could work.

Eric...I agree with your analysis but I do have 2 points to add. Also the RR Solar is R 3.5, not 3.6.

1) The RR Solar is indeed the standout in terms of warmth for the weight, but a lot of times this much R-value isn't needed. I personally have no need to add R-3.6 to my sleep system, so I'm looking for the pad that will add about R-1 for the least weight. With my NeoAir I've fairly pretty well on snow on several occasions and I'm just looking for a little extra safety margin.

2) This sorta goes against point #1, but I think there is a real possibility that Prodex will do better than R-1.1. Reflectix uses large bubbles which offer very little insulating value since the air is free to move around in the bubbles. Prodex uses CCF between the reflective layers, so it should be more insulating as the air can not move around nearly as much.

Prodex is almost like a thinner version of the RR solar. Both are CCF pads with reflective layers. Based on this, we can calculate a very rough R-value estimate for Prodex:

The RR solar is 19mm thick. We know the R-value of it without the reflective layer (3.1) because the old RidgeRest Deluxe is the same thing without the reflective layer. The R-value of CCF foam rises linearly, so a 5mm thick version of the RR Deluxe would be R-0.8. So Prodex at 5mm thick should be about R-0.8 plus the benefit of the reflective layer. This isn't totally accurate since they are different kinds of CCF, but I think we're in the same ballpark here.

We know that the reflective layer on the RR Solar adds R-0.4 even though it's only reflective on the top side. Prodex is reflective on both sides. The reflective stuff on the bottom probably won't do much, but it might help a bit. So as a rough estimate, Prodex should be about R-0.8 (5mm CCF) + R-0.4 (Reflective on top) + maybe a little more (R-0.1?) for the bottom reflectivity. So that adds up to a very rough estimate of R-1.3.

There's a huge number of assumptions in the above calculation and you could easily pick that estimate apart, but I think that the point stands that if you are looking for a pad to add about 1 to 1.5 R to your sleep system then Prodex does stand out as being the lightest option mentioned so far that does this.

Perhaps we could send a sample of Prodex to a BPL tester? I think Roger Caffin did R-value tests for that recent POE review and perhaps he could test a sample?

Edited by dandydan on 11/18/2010 14:38:12 MST.

dan ... the RR has air gaps in the ridges between yourself and the pad

since prodex is foam ... my bet is that it wont be much better or worse than putting mylar film on both sides of a cheap foam pad

A sleeping bag would fill any gaps in the top of the RidgeRest so I don't think those change anything. I think they're mostly just to save a little weight.

"my bet is that it wont be much better or worse than putting mylar film on both sides of a cheap foam pad"

If by 'mylar film' you mean reflective mylar film, then yeah Prodex would essentially be like a cheap foam pad with reflective mylar...but right now you can't buy that besides Prodex.

Edited by dandydan on 11/18/2010 16:54:26 MST.

I'd like to give this another go. It kinda fell off the map...

So a friend of mine got me a piece that is 28 by 21 and about 5 to 7mm thick and weighs 2.75 oz. I use it to suplement my neo short under my feet or where ever is cold. Easly twice as warm as my thinlight. Not as durable, it is delaminating in a few spots that fold often. (Quarter sized or smaller spots.) I have maybe 15 nights on it. By my calc a 72*20 pad would weigh 6.75oz aprox.

Thicker AND lighter! I like your calculations better than mine! :)

Have you tried making a cozy out of the material?

I'd like to buy a roll of it, who's in?

I'd forgotten all about this. I'd be in for a pad.

Me too, I'll try one out.

I haven't made a cosy because the piece i got second hand was so small. It was used to package fish... until i saw this thread, i couldn't find a source for it. I have used reflectix as a pad and cosy and like the prodex better as it SEEMS IN MY OPINION to be warmer and lighter, tho slightly less durrable. Im down for a group buy... two 72" pieces for me, or as much as $20 can get me. :)

here

This site shows an R value of 15.67 for 13/64" thick Prodex.

Doesn't seem right. Am I reading this incorrectly?

That is not an error, it is for use as an IR barrier with at least 4" of air space. It isn't really applicable to the use as a sleeping pad or cooking cosy, as the dead air space isn't there. My GUESS is that using this as a sleeping pad would provide an r value similar to other quarter inch foam pads of similar density (cheap blue foamies) with a bonus of ir reflection. I use the piece i have under my feet when it's not too cold, and move it under my inflatable when it gets colder, (maybe) utilizing the ir feature. seems to work good :)

ymmv

Edited by pecos on 08/01/2012 20:54:11 MDT.

I'll snag a master roll of 4' x 25' (or 4' x 50', if enough people want it).

Dan - 1
Chris - 2
James - 1
Me - 1

Anyone else?

Cheers,
Tyson

Tyson,

I'd like a 4' wide by at least 6 foot long piece.

Daryl

I made an error when I said I wanted 1, I want 2. That pretty much finishes up a 4' x 25' roll. If I still lived in Snohomish, this would be very convenient! Now I live in SoCal...

Okay, this is what I have:

Dan
(2' x 6')

Chris
(4' x 6')

James
(2' x 6')

Me
(4' x 6')

Daryl
(4' x 6')


**Chris (or anyone else), what do you suppose is the best way to cut this stuff?

Edit: It will be more like 6' 3" (give or take)

Edited by sheepNgeese on 08/02/2012 10:10:21 MDT.

Scissors or a razor, i had the best luck triming my piece with a razor on plywood.

I placed the order this morning. The total was $74.95. Please email me your shipping address. I will probably ship all of these USPS, unless someone has a special request. Suggestions? Let me know.

marshall (dot) tyson (at) gmail (dot) com

Cheers,
Tyson

Dan - $9.37 + shipping

Chris - $18.75 + shipping

James - $9.37 + shipping

Me - $18.75 + shipping

Daryl - $18.75 + shipping

email sent