Therm-A-Rest says breath inflation "perfectly safe" for pads?

When my pads have delaminated, it’s been more aesthetic than functional.  I just keep using it.  It slowly gets worse.  Doing a week trip – no need for any backup.  Maybe a month trip I might consider a backup or starting with a new one.

If the reflective layers started to lose that reflective coating it wouldn’t be a big deal.  At least if it was just a few places.  If most of the reflective coating was gone, you’d only lose a little of the insulation, you’d still have air layers with baffles to reduce convection.

I’ve always used the pads that partially self-inflate. They all required a few puffs to fully inflate.  But the reason I gave up Thermarests was not that, it was because they weren’t very comfortable. After trying a number of brands that were not much better, tried the Nemo’s and was sold.  Don’t know why they are more comfortable, but there is a big difference.  Maybe it is the more gel-like foam, but don’t know for sure.  It’s just less bouncy.

First tried the ‘Zor’ because it was extremely light, but one of the dog’s claws punctured it.  Easy to repair, but didn’t want it to happen again during a trip, so accepted a little more weight on a slightly heavier model.  Especially in rainy weather, considering the time for adhesives to dry, my intolerance for sleep interruptions, and dislike of sleeping without some kind of padding underneath, carrying a repair kit was not a complete solution.

Never had a delamination in the Nemo’s, but vaguely remember one in an old Thermarest.  At any rate, there have been no failures in the Nemo’s because of the few puffs, or any other reason outside of accidental piercing, by dogs or otherwise.

When weight is “less” of a concern and I want absolute comfort, I’m also a NEMO sleeping pad fan, especially the Tensor Insulated. I love that it comes in a regular wide.

I don’t care about mold. As some surely know, mold is how penicillin was discovered. For me a bigger reason to use a bag is deflation. When you blow up a mat with warm air from your lungs it will deflate meaningfully at night in cold climates.

When you blow up a mat with warm air from your lungs it will deflate meaningfully at night in cold climates.

Possible solution: Inflate your mat or inflatable pillow hard, a while before you go to bed. Let the air cool and the mat shrink. Just before you go to bed, add a couple of breaths to restore desired firmness. You shouldn’t have any trouble getting through the night, because most of the air will be cold already, and you’ll be adding body heat.

Used the same technique to inflate hundreds of whitewater rafts which have much more air inside. Pump up with warm air, drop raft in the cold river, wait a while, top it up again. Raft was often good to go for many days, if it didn’t have slow leaks.

— Rex

Rex,

I have had for years a similar problem trying to explain just how easy it is to overcome the famous silnylon sagging. You wait for the fabric to cool down then set the tent taut. Once the fabric has stretched it can’t stretch anymore.

Yet apparently the above will remain a misterry for many…

Inflate your mat or inflatable pillow hard, a while before you go to bed. Let the air cool and the mat shrink. Just before you go to bed, add a couple of breaths to restore desired firmness.

I have to do that sometimes even using a Schnozzel for inflation if it cools down a lot before bedtime.  It’s just part of the routine.

…just how easy it is to overcome the famous silnylon sagging. You wait for the fabric to cool down then set the tent taut.

Also part of the bedtime routine.  Occasionally the tent will do a little more stretching overnight, especially if it rains, but rarely enough to matter.

I’m always in the market for a new pad system but read some negative reviews on the Nemo Tensor Alpine and like with other pads it can leak.

Sadly the website has no mention of Rvalue which is a big negatory—and they probably left it off since the pad is really just an air pad with no fill insulation.  (Instead relying on a reflective thingie).  They do mention “good to -20F” but alot of pad makers use these low numbers for their pads.

And I don’t like pads with such thin denier numbers—like 20 denier.  I’m used to using beefier pad fabrics like 70 denier on the bottom, maybe 40 on top.

And I dislike the valves they use (like with the Expeds).  And I really dislike blowing up a pad with an external “bellows sack”.  Think I’ll stick with my blow-up twist-valve Thermarests.

I learned a bit more about the Exped a few days ago.

First the Schnozzle does work with the version I have . A mate has an older version DM than mine but the Schnozzle has the adaptor to work on both. (4 bags full of air did it)

Second , never say never with mats. As he was inflating the mats he was telling me how the one his partner had burst a bubble just after the 6th (or so) trip whilst his has worked for many years.

That very night a buffle burst on his. Almost identical to the one I had on my older DM that I finally ditched a week or so ago. (it had blown over 10 years ago but kept just in case I figured out how to fix it)

Thermarest delamination likely due to friction.

John S—explain.

Relevant extract from a Therm-a-Rest blog:

Cleaning your mattress preserves its life expectancy. It’s your body oils that can bring on your pad’s early degradation. Often times, mattresses that are neglected and dirty also start delaminating. Through research, we’ve discovered that the fatty acids in body oils make the film beneath the mattresses’ fabric gummy.

— Rex

Rex—This is what Thermy told me 20 years ago in an email—delaminations are caused by “body oils” and “overuse”.  Since the pads are airtight I’m trying to figure out how body oils pass thru the air tight and waterproof fabric barrier??

Any gearheads want to explain this to me??  If it can’t be explained then it may be an attempt by Thermarest to not address their improper glue choices.

@Tipi

Their comment may date from many years ago, when the fabric they were using were coated on one side (inside) only. It was probably a PU coating too.

Cheers

body oil could soak into an airproof material and cause the adhesive to loosen

like, put some oily food substance with tomato or pepper in a plastic food container and that container will absorb it and you can’t wash it off.  But, it seems like it stays close to the surface and doesn’t go all the way through the plastic.

maybe body oils could cause delamination

Another quote from Therm-a-Rest on the effects of mouth inflation on their pads:

“We have mattresses that are 30, 40 years old that come into repairs and are irreparable for whatever reason. We have cut them open and you can see that there’s no degradation in the foam because of mouth inflation …”

https://www.thermarest.com/blog/winglock-twinlock-valve-technology-overview/

For pads with reflective insulation or made by other manufacturers – who knows?

— Rex

PS – TaR also says their new valve yields “3x faster flow rate” not “3x faster inflation,” a subtle distinction that’s not understood by most consumers. Don’t let engineers write marketing copy!

Even if you inflate a pad with outside air (i.e., NOT your breath) in the afternoon…by the middle of the night, when the air has cooled, the air volume inside the pad will have decreased. Some people might confuse this with an actual leak.

Additionally. if you inflate the pad with afternoon air (when the air is warmer and can hold more water vapor) then, in the middle of the night, once the air inside the pad has cooled due to the temperature having dropped, water vapor will have condensed into droplets inside the pad. My wife and I have seen the water droplets (some pads use a very translucent fabric) on many a trip.

So, when we get home, we inflate the pads (again, NOT using breath (we use the Exped shnozzle sack), We thenl et them sit for a while at room temp (to allow the droplets trapped inside the pad to evaporate (i.e., turn back into water vapor). Then, we deflate the pad. We do about three cycles of that.

So, even without using your breath at all you can have moisture collect in a pad. Whether that can lead to mold or not I do not know. But I do know that the baffles inside a pad can suffer (i.e. fail) from hydrolysis, caused by any water, moldy or not.

But there are measure you can take to try to get the moisture out.

P.S. We never breathe a breath into our schnozzle sacks, instead, we fill them with air by a quick flick of the wrists.

I have the kind with a little bit of foam in it. It has lasted very long and weighs the same as my former cut-down zrest and takes only about 6-8 puffs of air. No problem with it whatsoever after a decade or so.

I don’t think a Thermarest sleeping pad can be judged by how old it is—as in decades—but by how many “bag nights” it has.  I find thru hard-gained experience that a Thermy inflatable lasts about 200-250 nights before either failure and replacement or “precautionary” replacement—as in—get a new one before the old one dies on Day 2 of a 24 day trip.

I always thought down mats were the only ones you shouldn’t be inflating with your breath.

>> I always thought down mats were the only ones you shouldn’t be inflating with your breath.

Until this happens:

That is, lots of condensation inside the mat. It does not help.
Yes, that was my mat and my breath.

Cheers

Yeah, I agree with Tipi. I bought a pair of originals that lasted about 300 nights each, since I have been only getting about 220. I have been through 6 of them now. I have not ever managed a puncture (knock on wood) but I know sooner or later…

In every case but one, they started to de-laminate/balloon before they actually started leaking, though older valves seem to be more difficult to use.