Highest Temp Your Xtherm is Comfortable; Lowest Temp Your Xlite is Comfortable

I have camped at 0F on an Xlite with a TR Ridgerest SolLite short and my backpack under my feet. I was warm, no cold spots.

I don’t have an XTherm.

“What’s the highest temperature you can tolerate sleeping on your Xtherm?”

Hmm…. What temperature can you tolerate sleeping on your bed mattress at home? (which is probably at least R-20)

Mattresses with higher R value are not “warmer”. They simply resist conductive heat transfer much better.

Therefore, a pad with a higher R value would theoretically be better at keeping you comfortable (thermally neutral) whether the ground temperature was either cooler than your body, or warmer. I remember cowboy camping on a plateau in the Grand Canyon on a summer backpacking trip. When I went to bed, my ccf pad was protecting me from the 80-90+ degree heat radiating off of the granite I was sleeping on.

One other thought: since the Xtherm uses a little bit of radiant barrier technology, it’s possible that your own body’s heat could inadvertently warm you to a level creating discomfort. But if this were to actually happen, why not kick your quilt off?

Regarding your second question, while I suspect you are asking for anecdotal experiences from folks, keep in mind that the “real world” R value of an X-Light is woefully small.

(Personally, since I have only used my X-lite with a ccf pad on top, I honestly can’t tell you how low I’ve camped with it, other than to say that the last time I used it with the ccf it was in high 30’s and I using a 40 degree quilt (with down pants & jacket).  But one’s experience would also have to depend on what the temp of the quilt I were using, the ground temp, what I had for dinner, am I a “warm sleeper”, etc…)

Thank you Matt for the feedback. My question was prompted by having only tried an Xtherm in cold (not very cold weather) and a few people telling me they found it too hot to use in warmer conditions. I’ve not yet tried the Xlite, and since I always take a CCF pad in cooler and cold weather, I was wondering about Xlite use in cold conditions together with a CCF and wondering if there’s an upper temp limit for the Xtherm.

Personally I’ve been hot sleeping on some mattresses in warm weather and kicking sheet and blankets off left me still uncomfortably hot on the mattress side (happened one summer in university with a stiff foam mattress). And even in warm weather I sleep better with a cover of some kind, like a thin sheet, rather than no cover.

Me too. For some reason, I always need a sheet over me, even if it’s paper thin.

Fwiw, my favorite sleeping mattress of all time was an old self-inflating “Luxury Edition” Thermarest from the late 90’s. It was at least R-6, but it had a very thin, fuzzy fleece-like surface (similar to what’s currently used on their “Dreamtime” mattress.)

On hot/humid days, I never felt clammy on it because the surface wicked away any sweat that was about to form. I could sleep right on top of it with a thin sheet, and always felt comfortable.

Nowadays, I sleep with a quilt inside a silk liner, directly on top of a ccf pad over an Xlite or more recently an Axl Air. Since the silk is between myself and the surface of the pad, I never experience the clamminess and sweating.

While “too hot” can be uncomfortable, “too humid” can be downright unbearable.

I have both. I’ve never found an upper limit for the Xthrm. The coldest night I’ve spent on it has been maybe 55 deg F.

The lower limit of the Xlite of course is a different story. Definitely can’t handle direct to snow contact. I was cold sleeping on snow even when the nights were in the 50s.

On bare, dry ground, I’d guess that I’ve been “OK” into the low 20s F – during the summery seasons – when days are warmer. In the winter, even on bare dry ground, it’s a different story, because the ground is colder as a result of the colder days.

I’m happy to use the XTherm all summer. If you camp year round and don’t want to buy a quiver of pads, the XTherm makes a lot of sense.

I use an Xtherm year round with no issues – two actually – a large and a shortened large (53” long).  The coldest was in a tent with air temp of -10f on snow.  Don’t know the temp of the snow but most likely much warmer than -10f.  The warmest I have used the Xtherm was mid 60’s and was fine.  I find in warmer temps that it is the non breathable nature of any coated fabric mattress to be the cause of most discomfort and not the r value of the pad.  I sleep on 14” of open cell foam at home but it breathes.  I also sleep in silk weight long base layers, when backpacking regardless of how warm it may be, as it adds a bit of comfort compared to direct contact with the pad and keeps things cleaner as well.

I use my XTherm for 3 season backpacking and have never been too warm, even when air temps were in the 60’s.  Good discussion on resisting conductive heat transfer.  It’s not like the pad generates heat that would make you too hot.  And you didn’t specifically ask, but I have used my Exped Downmat (R value approx. 8) indoors and never been too hot, but I have certainly been comfortable!

Thank you guys, I appreciate the feedback.

Matt and John, I think you nailed it. High humidity + lack of breathability of the surface material explain why some users report the Xtherm too warm in milder conditions. What conditions? I’d say high humidity with night temps of +68/70F. One friend I have in mind who complained about the Xtherm in summer is in the coastal Southeast, where hot humid summers are the norm.

Jenny in cold winter temps I’ve used the Exped Downmat 9 and 7. Super comfy and durable, but of course a lot heavier.

Dan and Ryan, hot + humid nights are probably a rarity in your stomping grounds as they are in N California, where cool nights are the norm and it’s hot for just a few weeks and even then it’s rarely too hot at night. In the NE with higher humidity it’s really only the hottest summer nights that may be an issue, and they’ll be uncomfortable in any case.

I’d possibly consider another lighter NeoAir for the warmest summer conditions, but just to save some weight.

I start to feel less comfortable with my xlite at around 35. More and more, I just grab the xtherm and don’t think too hard about it.

I was too cold on my x-lite around the mid-30s F, with a 10 degree bag.   I haven’t been too warm on the x-therm yet, but I could see it getting clammy against bare skin in the high 70s or low 80s perhaps.

I made the mistake of underestimating the low temps in Shining Rock, NC a couple of weeks ago and took my X-lite pad and 30deg Marmot Hydrogen bag. Slept in a two man MSR Hubba Hubba with my wife and woke up to 12deg temps and everything covered in ice. Somehow I slept warm the entire night wearing a pair of lightweight nylon pants, short sleeve shirt, and a montbell down jacket. Never got cold from underneath using just the X-lite. I’ve never used my X-therm above freezing.

^^^

“Somehow I slept warm the entire night …”

Remember user name. Ignore comments about tents, bags, and pads.

Ok so I’ve got an xtherm and a women’s xlite. I’m a 5’10” man.

I have found the xlite women’s with the ccf gossamer gear thin pad comfortable down to 15F at 12k feet in light snow and frozen ground. That total weight is 13.1oz. I think it’s like 3.9+0.6 R but the women’s pad is rated differently so I think this works well for the weight.

Ive tried my xtherm at 20f and that was comfortable at 30. However I sleep better knowing I’ve got the ccf pad as a little extra.

I know that wasn’t your question but hope it helps

So Greg, Is Brian not to be believed?

Ive slept on xlite at 17f, no problems .

Was starting to feel coolness, but i was warm.

A lot depends on your top insulation too

“So Greg, Is Brian not to be believed?”

Oh I believe him. But anyone who is comfortable on a uninsulated air matt, in a 30° bag, in 12° temps, has a “comfort perspective” that is irrelevant to me, struggling to stay warm on a R-6 matt, in a 15° bag when the temps are 35° and above.

He is a one end of the bell, I’m at the other.

Haha, sleeping warm definitely isn’t one of my problems. If I could just find a comfortable position that I could stay asleep in for more than a half hour I’d be set. I guess all that rolling around generates some heat.