Therm-a-Rest ProLite Air Mat Product Review

Good to see a review of this new model.

By the way, it's not called a Prolite 3, it's called a Prolite.

And the old Prolite 4 is now called a Prolite Plus.

You might want to change the article to have the correct name so as to not be confusing (as if that's possible with their screwy naming convention).

I am not sold on the Prolite (by any name). It failed on me part way through my JMT hike last year (just after leaving VVR going south), and despite numerous attempts at field repair, it continued leaking. At first, I located two slits on the underside that I patched. But after patching these leaks, more slits became apparent that I either had not noticed the first time, or developed after the first patch. This happened three or four times until I finally resigned myself to a flat pad for the remainder of the trip. This was not so bad until the last three nights (starting at Tyndall Creek) when the temperature dropped into the 20s at night (late August). That's when I missed the lack of insulating capability of a flat airmat. Upon my return, I took the pad back to REI, and have gone old-school, with an old-fashioned blue foam closed-cell, cut to the shape of a Prolite. A bit bulkier to pack, but lighter, cheaper, and totally flat-resistant.

I verified that – thanks Jerry! The changes are made everywhere but the URL, where I can't change things without breaking other things.

I've used my regular size Prolite for about 150 nights.

No problems with leaks.

Fairly comfortable to sleep on but I sleep better in a regular bed.

It doesn't slip on my silnylon, but that's because I coated the silnylon with silicone diluted with mineral spirits (1:4) so it's almost sticky.

There's all this buzz about the Neo-Air, but I think this Prolite is better – only slightly heavier, not as comfortable, self-inflating but I always add about two puffs, I think it's less likely to have an air-leak and if it did it would retain some warmth and comfort

+1 to the ProLite series. I've used one for years and it's served me well. The only time I've ever had a leak was definitely operator error. I was trying one of the thermarest chair converters and for some reason thought it was a good idea to have a seat next to the fire. Yeah…

If I were going to buy a new one I'd probably buy the women's version. It's only six inches shorter and has an R-Value of 2.8 instead of 2.2. A pack or extra clothes would easily make up the missing 6" as a pillow or footpad.

Very nice review as usual.

Another excellent review. Thanks.

Really enjoy the pictures with your views looking out of you tent. Beautiful places!

Roger,

As usual, great article.

Regarding ignoring the transient…it makes since that you would for R-value determining. But IMO that transient would definatly be a piece of info to consider. A long time to reach steady state means a long time of elevated heat loss.
Two pad w/ equal steady-state R-values but significantly different heat capacities will feel much different during that transient period. For pads of equal R-value I would want the one with the lower heat capacity (and thus the shorted trasient in your test).

James

Roger, how do you measure R value?

I've used the 3/4 pad for the past several years, purchased one for my oldest son before we went to Philmont, since then purchased another one for my youngest son at an rei attic sale, said it leaks. I patched the leak & I use it now with no problems.I too add air since I like a firm surface. As far as something under my legs I put clothes under by sleeping bag. I have no complaints with all our backpacking trips over the past three years and will be taking it back to Philmont this year.

> Two pad w/ equal steady-state R-values but significantly different heat capacities will feel much different during that transient period.

True, but …
I don't think the thermal mass of the airmat is more than 1% of a human body. (Actually, way less than that.) As such, I seriously doubt that the transient found during measurement will be significant in the field. Certainly, I have never noticed the effect myself, after sleeping on many of the mats.

Cheers

> how do you measure R value?

Ah yes. We have an article devoted entirely to the Thermal Insulation Measurement System I have built to specifically measure R-values. It will be published soon.

I will add that this is not the first one I have built: my team did build one when I was working for CSIRO Textile Physics many years ago. Anyhow, it's coming … soon.

Cheers

"I will add that this is not the first one I have built: my team did build one when I was working for CSIRO Textile Physics many years ago."

You aren't trying to gather wool over our eyes, are you?

–B.G.–

That should be an interesting article, Roger

You're probably right about the relative importance but it would still be interesting to confirm.

I am very surprised that you do not mention one of the big problems of the Therma-Rest: Delamination!

I have been hiking and cycling for the last 3,5 years straight and I am always using a Thermarest Prolite (3) short. In these 3,5 years I have gone through 5 (five!!!) thermarests – all exchanged under warranty due to delamination.

I want to mention that in this whole period and 5 mats I never had a single leak. But after about 6 months of constant use the mat starts delaminating. That means that on chamber created by the punch out bursts, connects with the chamber next to it and creates one big chamber. If you continue using the mat more and more chambers will burst and create a bigger and bigger bubble – until you cannot sleep comfortably on it any more.

I am treating my gear very carefully (never had a leak), so this delamination does not stem from mistreatment of the mat – I think it is a quality problem. The only reason why I continue using Thermarest is their worldwide warranty policy. When the delamination starts, I just exchange it. The problem is so common that dealers in various countries (Germany, US, Australia and NZ where I had to exchange mats) knew about it at once and exchanged it immediately with no questions asked.

I would like to see a technical explanation for this problem on BPL. When I last exchanged a Thermerest in Australia I received a standard letter from the Australian Thermarest distributor claiming that this problem is caused by bacteria and funghus growth due to contamination through body oils – which did not make much sense in my eyes.

Could you give some explanation for that problem?
Christine

6 months of constant use – 180 days

Most people would take years to use it that much

Maybe it would be reasonable for something to wear out after years of use

Maybe that's just beyond what the Thermarest mattresses are capable of doing

I don't think that half a year of constant use is an unreasonable amount of time for a sleeping pad – especially for one that is not exactly cheap either…

To give you a comparison:
I am using a Tarptent Contrail and it has gotten more than 400 nights of use – and is still doing fine. I only had to replace the zippers.
My WM sleeping bag has seen more than 500 nights of use and still does fine.

In comparison to that 180 nights of use is not really much…
I think that Thermarest is aware of the delamination problem, but as not many people use their mats that long they just accept the return rate for delaminated mats. Still I think that Thermarest produces mediocre quality – they have not been able to resolve the delamination problem in 4 years. The delamination occured with the "old" Prolite 3 (orange) mat as well as it does with the new Prolite (red) one.

Christine

Hi GT
Franco

". Still I think that Thermarest produces mediocre quality"

now that there is a pretty hard slam at a company made up of some very skilled and polite people.
i suspect that what might be a better choice of slams is that they produce products of excellent quality, but that do not possess outstanding longevity. (i bet we might all agree on that feature.)

those of us who use their products at length know well of the delamination issue. i sleep on one at home, and recently, as expected, it inevitably delam'd, and now has a big bubble in it.

you can see a delam coming. and except on a very long trek, it's hardly an issue in that they'll front you another one.

for along trip .. buy a new one. you can always use another air mattress.
considering the landfills heaped with castoff computers gratis microsoft, and hp printers tossed by the millions, a mattress repair now and again is small pick'ns.

it has been my experience that delam occur directly under where is pivot on my right elbow when moving about. i suspect that the elbow imparts considerable shear into the fabric, and this is a contributing factor.

questionable as thermarest longevity may be, those chinese ones from pacific outdoor are worse.

"it has been my experience that delam occur directly under where is pivot on my right elbow when moving about. i suspect that the elbow imparts considerable shear into the fabric, and this is a contributing factor."

That's interesting

I'll be more careful putting my weight on it with hand or arm when I get on or off

I'll now watch out for delamination and replace it if needed, thanks for bringing this up

I have had 5 delaminated Thermarests and the delamination occured in a different place each time. Therefore I don't think that outside pressure (like your elbow) has any influence on the problem.

For me the delamimation problem is a big issue. The problem usually occurs in the middle of nowhere and it can take me quite a while to get to a place with an outdoor shop. And then that outdoor shop must stock Thermarest and be willing to exchange them under warranty. When on a long hike I have other things on my mind than dealing with defective sleeping pads…. Some countries are very easy when it comes to warranty issues like the US or Germany. But in Australia for example you have to send the mat in for inspection and wait for them to send you a new one. On a long hike you cannot just wait for 10 days till Thermarest is so kind as to replace a defective mat. And in countries like Korea you don't have a chance to get a replacement.

I am still using Thermarest because other mats are probably still no better. But I still think that Thermarest quality is rather mediocre especially considering the rather high price and the persistence of a problem that is known for so long.

Again: It would be interesting to hear a statement for the BPL tech people on that subject. What is the cause for the delamination? Is it really funghus growth? What can the user do to prevent or delay the problem?

Christine

Hi Christine

Some of our TaR airmats are now many years (15+) old, and so far I haven't seen this problem on any of them.

> it has been my experience that delam occur directly under where is pivot on
> my right elbow when moving about. i suspect that the elbow imparts considerable
> shear into the fabric, and this is a contributing factor.
I would go further than that and say it was the direct cause of the delamination. I know we do avoid this sort of twisting on our mats. What is happening is probably not 'delamination' per se, but ripping of the very light foam core.

I bet TaR know exactly what causes the delamination. That TaR are willing to stand by their product and take the hit without argument speaks a lot for the company. You simply cannot have UL and bullet-proof at the same time. Make your choice and pick the appropriate brand and model.

Cheers

The delamination problem is not caused by age, but by use!

Also, you would not have this problem in a 15 year old mat simply because delamination only occurs in mats with punched out foam – and this type of mat was not produced 15 years ago….

Christine

> you would not have this problem in a 15 year old mat simply because delamination only occurs in mats with punched
> out foam – and this type of mat was not produced 15 years ago….

Um … our TaR Deluxe LE mats (limited production) which we bought in the mid-90s and still use on snow trips are cored. And our original TaR mats which they replaced were cored too, and are still in use by one daughter and her family.

Is there a difference between 'cored' and 'punched out'? Dunno, but it would seem that others are still using similar old mats quite happily.

Cheers