Heat transference between layers (when camping)

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Vorpal
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Re: Heat transference between layers (when camping)

Postby Vorpal » 3 Sep 2019, 7:05pm

Tangled Metal wrote:To think a double layer of think nylon or polyester is a great insulator! I'll wrap my house in it and watch my heating bills shrink this winter!

Sorry for the facetious comments above. The tent only cuts out the wind and rain. It offers no insulation in itself. You can find shelter without a tent or tarp and just using your sleeping bag and mat if you know a good location. Not to recommend it as a tent or tarp is kind of reassuring.

Mat and sleeping bag are the only real ways of getting your insulation right. You have to get the right ones for your intended conditions and your personal choices. The tent is just the windbreak.

I disagree. The tent doesn't hold much heat, but it does hold some. Most tents have an inner and an outer, and they trap air between. Thin layers of nylon may not be *great* insulation, but it is *some* insulation.

A 4 season tent does a better job of that, as it is designed to do so. An extreme weather winter tent will do even better.

I certainly would rather sleep in a tent on a cold night than just a mat and sleeping bag under a tarp. A bivvy bag is another alternative, but that puts another layer of insulation around you. It's probably a more effective way to stay warm than a tent, as long as it's not too cold for your face, or severe weather.
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Re: Heat transference between layers (when camping)

Postby mattheus » 4 Sep 2019, 3:49pm

So is the warmest test the one that only traps a thin layer of air around you (and your bag); thus limiting convection effects?

(of course you lose the comfort of being able to sit-up. And store your kit inside with you. And watching your wide-screen TV, etc ... )

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Re: Heat transference between layers (when camping)

Postby Vorpal » 4 Sep 2019, 6:53pm

mattheus wrote:So is the warmest test the one that only traps a thin layer of air around you (and your bag); thus limiting convection effects?

(of course you lose the comfort of being able to sit-up. And store your kit inside with you. And watching your wide-screen TV, etc ... )
For two tents that are otherwise equivalent, the smaller one will hold heat better than the bigger one. Of course other factors typically affect it as well, such as shape, whether your kit is inside or out, etc. The space taken up by kit might help a little with staying warmer, especially if you bring it in before the temperature drops much at night. I doubt that most people would be able to tell the difference.

The difference between a small one person tent and a 2 person tent is likely to be more noticeable, but I still suspect that not everyone would be able to tell the difference.
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Re: Heat transference between layers (when camping)

Postby sizbut » 5 Sep 2019, 12:11am

Indeed, the size of tent is a factor. Our 4-person tent, where I can stand in any part including the sleeping compartment, is great in summer, but distinctly cold at other times. The number of bodies can't heat the space as fast as it cools and the space is big enough to have its own internal convection even when sealed. So yes, this weekend (tomorrow actually) I'll be in a small 2-person tent even though it means I'll only be able to sit-up.

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Re: Heat transference between layers (when camping)

Postby horizon » 5 Sep 2019, 12:46pm

Vorpal wrote:
A 4 season tent does a better job of that, as it is designed to do so. An extreme weather winter tent will do even better.



Looking at various tent ranges, I get the impression that a four season/extreme tents will be much stronger and have, for example, snow valances. But I'm not sure it will be warmer as the actual material is still the same. So size may be more important: would a two-season small tent be wamer than a four-season 4-man tent with one person in it for example?

Having said that, an old cotton extreme tent might be warmer than a modern high-end synthetic.
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Re: Heat transference between layers (when camping)

Postby horizon » 5 Sep 2019, 12:54pm

Vorpal wrote: I doubt that most people would be able to tell the difference.

The difference between a small one person tent and a 2 person tent is likely to be more noticeable, but I still suspect that not everyone would be able to tell the difference.


I'm going to be taking two temperature gauges from now on - one for completely outside and one for the inner tent. I don't know how many degrees will be noticeable or indeed matter (two? three? five?) but I think it will be good to establish the role of the tent itself in keeping warm.

I have argued in the past that cotton is warmer than synthetic but weight for weight it might not be whereas tent size might be very beneficial and the tent itself (of whatever make or size), better than outside.

BTW, if it is true that smaller is better (i.e. warmer), this augurs extremely well for cycle camping, obviously! :D
I have two doctors, my left leg and my right leg. (G. M. Trevelyan)
PS I always wondered why the YHA HQ was called Trevelyan House. :)

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Re: Heat transference between layers (when camping)

Postby Sweep » 5 Sep 2019, 1:02pm

horizon wrote:I'm going to be taking two temperature gauges from now on -

I bought a Lidl temp thing for just that purpose (old thread on here) - measures inside and outside temp in one neat unit.

It seemed pretty good/accurate.

The wire dropped off it eventually though so now it's inside only.

Still, worth looking out for if it makes a return.
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Re: Heat transference between layers (when camping)

Postby Vorpal » 5 Sep 2019, 1:07pm

horizon wrote:
Vorpal wrote:
A 4 season tent does a better job of that, as it is designed to do so. An extreme weather winter tent will do even better.



Looking at various tent ranges, I get the impression that a four season/extreme tents will be much stronger and have, for example, snow valances. But I'm not sure it will be warmer as the actual material is still the same. So size may be more important: would a two-season small tent be wamer than a four-season 4-man tent with one person in it for example?

Having said that, an old cotton extreme tent might be warmer than a modern high-end synthetic.

Extreme cold weather tents normally have a double layer inner and a stove/heater vent. The material on some brands is also thicker &/or coated (e.g. with silicon). I imagine that there is plenty of discussion about that sort of thing on camping or survivalist sites & forums?
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Re: Heat transference between layers (when camping)

Postby horizon » 5 Sep 2019, 1:22pm

Vorpal wrote:
Extreme cold weather tents normally have a stove/heater vent.


Now we're talking. :D

Actually I was looking at Hilleberg but it could be that even they do some specialist stuff.
I have two doctors, my left leg and my right leg. (G. M. Trevelyan)
PS I always wondered why the YHA HQ was called Trevelyan House. :)

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Re: Heat transference between layers (when camping)

Postby Vorpal » 5 Sep 2019, 2:49pm

horizon wrote:
Vorpal wrote:
Extreme cold weather tents normally have a stove/heater vent.


Now we're talking. :D

Actually I was looking at Hilleberg but it could be that even they do some specialist stuff.

There are a number of different types of winter tents. An all-purpose winter tent like a Hilleberg Jannu is somewhat different than an extreme cold weather tent, like North Face ECWT or an Arctic Oven.

If you will be camping in places with heavy snowfall, you might make a different decision than a 4 season tent for the UK and yet a different decision for a mountaineering tent for Alpine expeditions.

BTW, apparently I was mistaken that extreme cold weather tents normally have a stove. That's the impression I've had, but a quick google shows me that's only one type. Here in Norway, I have encountered people in the forest with lavvus and small wood burners.
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Re: Heat transference between layers (when camping)

Postby horizon » 5 Sep 2019, 2:59pm

Vorpal wrote:There are a number of different types of winter tents. An all-purpose winter tent like a Hilleberg Jannu is somewhat different than an extreme cold weather tent, like North Face ECWT or an Arctic Oven.

If you will be camping in places with heavy snowfall, you might make a different decision than a 4 season tent for the UK and yet a different decision for a mountaineering tent for Alpine expeditions.

BTW, apparently I was mistaken that extreme cold weather tents normally have a stove. That's the impression I've had, but a quick google shows me that's only one type. Here in Norway, I have encountered people in the forest with lavvus and small wood burners.


Here's the link to the Hilleberg Nammatj:

https://hilleberg.com/eng/tent/black-la ... matj-2-gt/

It's a bit misleading as it shows an all-round tent (they say, "a weekend walk in the local hills") being used in snow. So I suppose it's saying - here's a winter tent you can use in the summer! I was camping in 6 deg C a couple of weeks ago (SW England, lowland, August) so there's a fair bit of camping that might be termed challenging long before you get to the snow line.
I have two doctors, my left leg and my right leg. (G. M. Trevelyan)
PS I always wondered why the YHA HQ was called Trevelyan House. :)

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Re: Heat transference between layers (when camping)

Postby Vorpal » 5 Sep 2019, 3:15pm

I guess it depends what you want from your tent.

I don't think I would bother with the weight (or cost!) for any above / near zero temperatures. Last weekend, I was comfortable in a 3 season Helsport, even though I woke up to frost on the tent (Norwegian mountains). I think if I added an extra bag on my sleeping bag, I'd be okay down to -5 or so. I have to admit that I don't have much taste for winter camping anymore, but I might be persuaded to try the lavvu & mini wood burner on a skiing trip or something. I don't think that a lavvu and wood burner weigh any more than the Hillberg you linked to, and it eliminates the need for a cooking stove. It does require fuel of some sort, which could be a disadvantage, if you have to carry it.
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Re: Heat transference between layers (when camping)

Postby horizon » 5 Sep 2019, 3:55pm

Vorpal wrote:
I don't think I would bother with the weight (or cost!) for any above / near zero temperatures. Last weekend, I was comfortable in a 3 season Helsport, even though I woke up to frost on the tent (Norwegian mountains). I think if I added an extra bag on my sleeping bag, I'd be okay down to -5 or so.


I think this thread has been really helpful - it's been pointing to solutions (e.g. smaller tent, using a hat) that don't involve specialist equipment but using what you have better, as you have said yourself. Having said that, I do think that it is possible to find UK conditions challenging even in summer and obviously just with a bike.
I have two doctors, my left leg and my right leg. (G. M. Trevelyan)
PS I always wondered why the YHA HQ was called Trevelyan House. :)