Forum Index » GEAR » Radiant sleep pads in summer


Display Avatars Sort By:
Kier Selinsky
(Kieran) - F

Locale: Seattle, WA
Radiant sleep pads in summer on 03/27/2012 17:08:06 MDT Print View

Just thinking something through here - the NeoAir all season, XLite, and upcoming XTherm all get their R values through reflective barriers in the pad. Is there any data on how these will perform in summer? In other words, is there a risk that the radiant XTherm, at an R value of 5.7, will be too hot in summer? As opposed to a traditional self inflating foam mattress.

My plan has been to get an XTherm to use through all four seasons, but wondering if that's just going to make me sweat through the summer.

Lee Fitler
(tdilf) - F
Thermarest on 03/27/2012 18:30:36 MDT Print View

Is it possible that you could just turn the pad over and use the other side to get less radient heat.

Steven Paris
(saparisor) - M

Locale: Pacific Northwest
Radiant sleep pads in summer on 03/27/2012 18:49:42 MDT Print View

The radiant layers of the NeoAir/X-Therm/X-Lite pads are inside, basically coating the internal structures. This is unlike the RidgeRest and Zlite lines, where the radiant coating is on one side of the outside of the pad.

Btw, Kier, I was wondering the same thing about any of these insulated/radiant pads for the PNW, where there aren't really that many months where I think they would be too hot. I guess here you could always buy a RidgeRest SOlite for August/early September when the temps are maybe in the high 50s or low 60s at night.

Kier Selinsky
(Kieran) - F

Locale: Seattle, WA
Re: Radiant sleep pads in summer on 03/27/2012 19:34:59 MDT Print View

I guess here you could always buy a RidgeRest SOlite for August/early September when the temps are maybe in the high 50s or low 60s at night.
There ain't no way I'm spending that kinda money on an XTherm to spend a few months on foam! :) No but really, I like the idea of the XTherm because between its lightness and warmth, it's One Pad to Rule Them AllTM.

But with all the radiant shininess, I can't help but think of supermarket chickens turning on the spit surrounded by all the reflectiveness and wonder if I'm not going to roast as well.

Nathan Watts
(7sport) - MLife
Re: Radiant sleep pads in summer on 03/27/2012 20:05:34 MDT Print View

You will still lose heat to the ground. The R value is an indicator of what rate you will transfer heat, but so too is the ground temperature, or rather the difference in temperature between your body and the ground.

Likely you coul easily make up for a more efficient pad by losing heat from the top side via venting or a thinner bag or quilt.

Barry P
(BarryP) - F

Locale: Eastern Idaho (moved from Midwest)
Re: Radiant sleep pads in summer on 03/28/2012 13:01:20 MDT Print View

It’s only 90F at night with 90% humidity; I’ve ran into that a lot in the Midwest.
And then you’re sleeping on a pad that radiates your body heat back up to you. Great.
On those trips I only take an Egyptian Cotton liner (no bag/quilt). This is the only time for me that I love cotton. It’s much easier for me to lay on cotton than on nylon when hot and sweaty.

So yep, I’ll keep my hot neoair and cover it with cotton.

Good luck in the hot humid sleep.

-Barry

Nigel Healy
(nigelhealy) - F

Locale: San Francisco bay area
Re: Radiant sleep pads in summer on 03/28/2012 13:52:32 MDT Print View

I know more about physics than mats, but I'd say the loss by radiation is linear on the temperature difference between the two surfaces, i.e. a much colder ground will chill quicker than a warmer ground, and this is linear on temp difference.

So a high R value is reducing this radiating loss. The smaller the temp difference, e.g. warmer ground, the linear reduction of this loss, so the less the impact of the high R value. For example if the ground is the same temp the R value is irrelevant. So logically you can use high-R in heat via using heat loss from other means (breeze, no bag, thin bag, etc). FWIW I used an All Seasons in a warm September and just pushed my bag to my waist.

So theoretically the only downside of an Xtherm is your are wearing an expensive bag when you dont need the insulations so it lasts less winters. I bought a All Season regular and it packed size same as my Prolite regular so backpedalled to a Neoair short which is about half the size.

Bradley Danyluk
(dasbin) - MLife
R-Value on 03/28/2012 13:54:04 MDT Print View

Keep in mind your mattress at home likely has a far, far higher R-Value than any pad you can bring with you, and you probably sleep on it all-year round (right?)

Nigel Healy
(nigelhealy) - F

Locale: San Francisco bay area
two pads on 03/28/2012 14:42:50 MDT Print View

If you want an all-seasons solution, consider the lower cost Neoair (used as-new, discounted new purchase) and a CCF. You might own one or both of these and so cost can be less than a new Xtherm. Also affords some redundancy if event of puncture, and obviously you can use just one of them in hot weather, say the Neoair being the comfiest.

Unfortunately, whilst the idea has some $ and R-value merits, it sucks on the weight. Xtherm is lightest Thermarest solution for that those high R-value needs.

Example, Neoair short R=2.4 9oz, CCF example Zlite Sol R=2.6 14oz. Combined R=5 (on the torso area) 23oz. Compare to Xtherm regular R=5.9 15oz.

There's also the women's Xlite only in regular (but shorter) R=3.9 12oz.

I'm sure there some creative combinations taking what one owns or looking at sales items.

Nigel Healy
(nigelhealy) - F

Locale: San Francisco bay area
Re: R-Value on 03/28/2012 14:45:22 MDT Print View

"Keep in mind your mattress at home likely has a far, far higher R-Value than any pad you can bring with you, and you probably sleep on it all-year round (right?)"

Your home mattress breathes a lot better than a plastic Thermarest Xtherm.