Foam under or over

[Rightfoot]

Heading out this weekend to Red River Gorge. Over night temps in the low teens. I have a neo aire and ridge rest foam pad. Total R value is 6.2. Should I put put the foam
pad under the neo aire or on top.
regards,
Rightfoot

[egilbe]

Depends on who you ask. I prefer foam on the bottom, but others will disagree.

[Shutter]

Wouldn't it make most sense to lay directly on whichever has the highest R value? Highest R value on top, lowest R value on bottom.

[Dogwood]

This weekend at RRG light winds 5 mph, no rain, night time lows at 14*. If it rains tonight(50%) and snow/showers Thurs(60%) ground will likely be damp. I'd be cowboy camping which I really enjoy particularly in cold temps. Mylar ground sheet, 1/8-1/4 CCF, Womans NeoAir, Katabtaic 15* Sawatch quilt or FF 20* Swallow UL. With the Sawatch I likely wouldn't need the CCF. Foam pad would be under the NeoAir Xlite Womans.

You have the R value needed if you are sleeping in an enclosed tent on the ground with a 15-20* sleeping bag with an accurate temp rating so no need for the mylar. I don't see a world changing difference to warmth with that being the case where your pace the CCF pad. Personally, I like the inflatable to the top under this scenario to warm the air inside it without a restless missing turning sleeping position. Maybe, if you toss and turn and are a side sleeper the CCF can go on top.

No wrong or right just my opinion. I think you'll be fine either way. Do what's most comfy for ya. Enjoy the RRG with some light snow. Sleep on the edges of the escarpments. With the leaves off the trees and partially cloudy but occasional clearness the night should be gorgeous for cowboy camping.

[T.S.Kobzol]

Foam on top

[Dogwood]

Foam on top

Is that when you're hanging or even when on the ground?

[nsherry61]

On the ground, at least when it is below zero, I find foam on top to be noticeably warmer. Like, a lot warmer. I don't know why.

I'd rather put the CCF underneath. It seems neater and more stable and better looking, and more logical and, and, and, BUT it's warmer on top, at least when it is really cold and you're pushing the temperature limit of the pad system.

[Tipi Walter]

On the ground, at least when it is below zero, I find foam on top to be noticeably warmer. Like, a lot warmer. I don't know why.

I'd rather put the CCF underneath. It seems neater and more stable and better looking, and more logical and, and, and, BUT it's warmer on top, at least when it is really cold and you're pushing the temperature limit of the pad system.

I agree with this and TS Kobzol---foam on top. But why believe us---just do it both ways and see for yourself.

[SWODaddy]

An air pad is more susceptible to heat transfer via convection with the cold air, whereas a CCF pad is more susceptible to heat transfer via conduction with the cold ground (think I got the terms right, but you get the point).

Short answer: foam on top.

[Dogwood]

On the ground, at least when it is below zero, I find foam on top to be noticeably warmer. Like, a lot warmer. I don't know why.

I'd rather put the CCF underneath. It seems neater and more stable and better looking, and more logical and, and, and, BUT it's warmer on top, at least when it is really cold and you're pushing the temperature limit of the pad system.

I agree with this and TS Kobzol---foam on top. But why believe us---just do it both ways and see for yourself.

Now we get top the place where a mixed under insulation system with an inflatable pad in the mix and the inflatable psssts you just lost your major R Value pad if the inflatable is next to ground with the CCF on top. This could have been prevented if the CCF was on the bottom. NOT GOOD losing your main insulation in 14* temps?

That's why I said and I ask how are you sheltering if at all...tent, hanging, cowboying, groundsheet?, type of ground, quilt, sleeping bag. temp rating of either the bag or quilt in regards to the lowest environmental sleeping temp...

[Dogwood]

An air pad is more susceptible to heat transfer via convection with the cold air, whereas a CCF pad is more susceptible to heat transfer via conduction with the cold ground (think I got the terms right, but you get the point).

Short answer: foam on top.

And what happens if the OP is cowboy camping? What happens if no groundsheet is being used? Do you still suggest laying the higher R Value Neo Air inflatable directly on the ground risking deflation? It happened to me on a Sheltowee Trace Thru-hike having a very cold night only on a 1/4 CCF pad using a quilt that was 5* rated above the minimum night time temp. Shivered most of the night despite wearing everything I had and putting my knees to feet in my empty backpack.

[nsherry61]

An air pad is more susceptible to heat transfer via convection with the cold air, whereas a CCF pad is more susceptible to heat transfer via conduction with the cold ground (think I got the terms right, but you get the point). . .

Right or wrong, it sounds great. I'll run with it. Now we know. Thanks!

And what happens if the OP is cowboy camping? What happens if no groundsheet is being used? . . .

So, use a friggen ground sheet. Duh.

[Dogwood]

Duh? Doo da da.

You're missing the point. Does the CCF pad under the Neo Air give it greater or less protection from deflation? Could this be important if the main R Value component in the under insulation is the R Value of the inflatable pad?

[jellyfish]

An air pad is more susceptible to heat transfer via convection with the cold air, whereas a CCF pad is more susceptible to heat transfer via conduction with the cold ground (think I got the terms right, but you get the point).

Short answer: foam on top.

Science the heck out of this problem. Love it.


Sent from my iPhone using Tapatalk

[rocketsocks]

The way it was explained to me and the way I remember it is the small indents in the ccf pad take less energy to heat up when coverd by a layer (ie; person in bag) than the larger volume of the air mattress below...but I don't mind saying that after reading this thread...I'm more confused than ever blinded by science

i put my my ccf on top

[Engine]

Depends on who you ask. I prefer foam on the bottom, but others will disagree.

+1 Bottom protects pad, stops slipping, adds same R value. (but in all fairness to the put it on top folks, I haven't tried it with my current 1/8" GG pad)

[T.S.Kobzol]

Is that when you're hanging or even when on the ground?

Ground. From experience, and I did try it both ways.


Coincidentally also in a hammock as the bottom quilt is always under the hammock and I slid the foam in the double sleeve. I have never tried inflatable pad in a hammock and probably never will...doesn't seem to make sense to me.

[Tipi Walter]

One caveat with foam pads---These things are bulky and usually placed on the outside of the pack whereby they occasionally pick up thorns from briars or hawthorn trees or whatever else. These spikes break off into the foam and are invisible. THEN when you sandwich your inflatable with the foam the thorn pokes out and punctures your beautiful inflatable. It can happen. CCF's act like pin cushions . . . at times.

[Starchild]

Ever sleep on a foam mattress or a mattress with a foam topping, it is very warm. Air mattresses are colder than normal mattresses.

[SWODaddy]

And what happens if the OP is cowboy camping? What happens if no groundsheet is being used? Do you still suggest laying the higher R Value Neo Air inflatable directly on the ground risking deflation? It happened to me on a Sheltowee Trace Thru-hike having a very cold night only on a 1/4 CCF pad using a quilt that was 5* rated above the minimum night time temp. Shivered most of the night despite wearing everything I had and putting my knees to feet in my empty backpack.

The context of the question was clearly heat retention. My answer was appropriate in that context, so I don't know why you're trying to quibble over "what if" scenarios. Nobody here needs lectured on the fact that a foam pad is more durable than an air pad, that's obvious.