What we've learned about Insultex

[MacEntyre]

So wouldn't putting IX on the outer surface of a KAQ produce similar results?

Depends on the conditions and the occupant, as always with condensation.

[sclittlefield]

Depends on the conditions and the occupant, as always with condensation.

Very true. Folks who use the Hennessy SS have reported good results. That's a vapor barrier bottom and OCF. So it clearly can work for some.

There are certainly trends to look at, and even when the science is sound - there are so many variables that two people with the same setups in the same place on the same night can have very different results.

[ikemouser]

Thankyou for this thread, i missed out on alot of the insultex stuff, nice cathcup. Looking forward to your summaries everytime something goes down mac.

[JohnSawyer]

Excellent report-out. I'm still trying to figure out how to keep my (always cold) feet warm with a 2/3rds quilt.

So what I'm hearing is:

1. Don't put a multi-layer IX pad under my legs as compressing the IX is an issue.

2. Tie up an extender to my current UQ, with another layer of conforming insulation between the hammock and the IX?

Since I sometimes still have CBS with my UQ (did I mention I'm a COLD sleeper?), adding a smal piece of IX under the south-end of the UQ may fix that...

If that would work, does anybody have 1-2yds of IX they'd be willing to part with? :-)

[MacEntyre]

1. Don't put a multi-layer IX pad under my legs as compressing the IX is an issue.

I use IX under my legs without issue...

2. Tie up an extender to my current UQ, with another layer of conforming insulation between the hammock and the IX?

That could work well! Try it first without the conforming layer.

Since I sometimes still have CBS ...adding a small piece of IX under the south-end of the UQ may fix that...

Done that! Works for me!

If that would work, does anybody have 1-2yds of IX they'd be willing to part with? :-)

PM sent.

[Albert Skye]

I've not personally inspected Insultex but I've read about it and seen these pictures (thanks to Grizz! ).

As it appears to me, Insultex basically provides an insulated membrane; i.e., the air trapped by the membrane is the primary insulator (not the membrane itself), much like an air-filled plastic bag (Garlington Insulator), but better because convective heat loss and condensation is reduced due to its low thermal conductivity (the insulation of the membrane itself).

The more layers the better, but I think each layer should be supported to prevent collapse of the air space. A small amount of down (or other fluffy stuff) might work well, or one or more inflatable airtight chambers (plastic bags are quick and easy).

In any case, it seems that Insultex is very similar (if not essentially identical) to some thin foam packaging materials which are available in various forms (airtight or perforated, polypropylene or polyethylene, thick or thin, &c.); it can be purchased new on rolls or scavenged from the various products it wraps. It can be somewhat fragile, and I imagine that's why Insultex has a layer of scrim (though I don't see it the pictures above); otherwise, I don't know what makes Insultex different.

Comments?

[MacEntyre]

I think you have it for the most part, Albert!

Insultex may be more breathable than we think. That is the biggest difference between it and generic polyehtylene sheet.

Also, the scrim does a lot to create the necessary air gap underneath the covering material. It doesn't take much.

A down Karo quilt with IX on the outside is something I would like to see... maybe I'll make one next winter!