Warm tents?

[nonaeroterraqueous]

I spent some time investigating four seasons tents and ended up buying a very nice tent that was fairly expensive. I wanted to be able to camp out in the cold, in the snow, in January. The fly was full, and the structure was a freestanding dome, and it had all the features of an ideal tent, I thought, but when I took it out in freezing weather it only measured a 10º F (5.6º C) difference between outdoor and indoor temperatures. That was after being inside it four several hours to warm it up. After looking into it, I discovered that this is about the best that can be expected from the best of tents, except...

Then I discovered the Crua Tri tent, which is about the only tent, anywhere, that actually adds insulation to the walls. It has two downsides, though. Firstly, it was invented almost yesterday, and it has no reviews, anywhere. Secondly, it costs almost $600, which is a lot to invest into a small tent that I know almost nothing about.

Right now, I'm looking into the prospect of making my own tent liner, using a pleated synthetic fabric with polyester fill. Doing anything so unusual to solve such a common problem tends to have its drawbacks, namely that if I've never heard of anyone doing it before, then it probably hasn't worked for anyone.

So, the question to anyone out there is this:

1. What's the greatest temperature difference you've actually measured between the inside and outside of a tent (at night), and the kind of tent?
2. Or, have you ever modified or augmented a tent to make it warmer? Did it work?

Some have argued that it's the sleeping bag, and not the tent that makes all the difference, but the sleeping bag does nothing for inhaled air, which exposes considerable bare surface area to a humid, cold, moving air, and represents a huge loss of heat.

 

[Murby]

My wife and I have spent a lot of time cold weather camping while hunting..

Short of a canvas tent with a stove, there's nothing you're going to find or build that will raise the temperature inside the tent.
First, unless you have a heat source inside the tent, what reason is there for it to ever get warmer than the outside air temperature? In order to heat the tent, there must be a heat source. If you're considering your body as a heat source, then that itself is a problem because it means you're not properly insulated.

Breathing cold air will NOT make you cold.. if you feel cold, its because of a poor quality sleeping bag and/or inadequate ground insulation. The air you breath isn't really an issue until the ambient temps drop below zero or so.
We've slept comfortably in 5 degF weather. You need an air mattress and a good quality bag as well as good quality cold weather clothing.

The reason you can't insulate a tent is because they require air flow through the tent.. all the insulation in the world isn't going to make a difference if you have giant air leaks... if you close up those air leaks, you can quickly build moisture inside the tent making things even worse.

What kind of camping do you do? When we went hunting, our campsite was there for two full weeks so we set up in a semi permanent way.. We even had a campfire heated hot shower setup.

If your campsite is long term and you're not climbing mountains and moving every night, I might recommend getting a canvas tent.. then you can put a wood stove in it and even the air will be warm and toasty.

 

[nonaeroterraqueous]

Short of a canvas tent with a stove, there's nothing you're going to find or build that will raise the temperature inside the tent.
First, unless you have a heat source inside the tent, what reason is there for it to ever get warmer than the outside air temperature?

Actually, yes. I have made a tent much warmer by covering it with a blanket. That was without any artificial heat source.

Breathing cold air will NOT make you cold.. if you feel cold, its because of a poor quality sleeping bag and/or inadequate ground insulation.

I don't mean to sound argumentative, but...I am. I've used a heat exchanging mask, and I can confirm that sparing exhaled heat will warm an entire body. I've used the warmest sleeping bag that I can get my hands on, and the fattest air mattress, and covered the mattress and the rest of the floor with a comforter, and I've lied awake at night wishing I weren't cold. When you're lying in that sleeping bag, if you feel the outside of it with your hand you'll feel no heat coming from the bag. That's because no significant heat is coming from the bag. Yes, I'm still cold, and you can't possibly say that the warm air I feel coming out of my mouth (yes, I'm a mouth-breather) is not the cause of heat loss. I'm losing heat through my breath. I can feel it leaving through my breath. Don't kid me, man. The surface area of the inside of your lungs is the same as half a tennis court, and the humidity is 100%, and the wind chill factor is never zero. That's going to make a difference. At some point, adding more insulation to the outside of your body won't make any appreciable difference, because you're blowing heat right out of your nose (you nose-breather, you), while the outside of your clothing or sleeping bag is cold (not losing heat).

The reason you can't insulate a tent is because they require air flow through the tent.. all the insulation in the world isn't going to make a difference if you have giant air leaks... if you close up those air leaks, you can quickly build moisture inside the tent making things even worse.

Yeah, it probably gets more humid inside. It might be a problem. Still, like I say, a blanket over the top of the tent works wonders. It just doesn't work well in a rain storm. Granted, the tent needs to breathe, so I can. If I'm not suffocating, then it's breathing enough. If it breathes more than that, then I'm losing heat needlessly. Perhaps the moisture has never been a problem where I've camped. It tends to get pretty arid. I know people keep saying that you can't insulate a tent or the moisture will build up, but I've already done it on an experimental level and it worked fine. Heck, my bedroom is insulated, and I don't wake up each morning in a pool of water.

What kind of camping do you do? When we went hunting, our campsite was there for two full weeks so we set up in a semi permanent way.. We even had a campfire heated hot shower setup.

I do all kinds: Back woods light backpacking; heavy backpacking with a Dixon Roller Pack (a trailing backpack); improved campgrounds. The heavy backpacking is fun, toting large quantities of supplies for longer treks into the middle of nowhere. Summer camping is fun enough, but it means competing with others for space. Pushing into the colder months means being totally alone, out there in the snow, on a mountain in the middle of nowhere. It gets really quiet.

If your campsite is long term and you're not climbing mountains and moving every night, I might recommend getting a canvas tent.. then you can put a wood stove in it and even the air will be warm and toasty.

Aah, that sounds nice. It's the only way I haven't camped, yet, I think. There never seems to be a yurt when you need one. The closest I ever came to that was a canvas tepee, and it was quite cold. You could almost see your life flying away through that blasted hole in the ceiling.

 

[Murby]

Actually, yes. I have made a tent much warmer by covering it with a blanket. That was without any artificial heat source.

Where do you think that heat is coming from? Thermal energy doesn't just appear out of now where, it has to come from someplace, that place is your body, and yes, even the heat expelled from your breath.

The one thing that covering the tent will absolutely do is to increase the moisture content inside the tent.. When the moisture content goes up, so does the heat loss.

If you're a cold weather camper, you should know this part.. When you fall into freezing water, what's the first thing you're supposed to do when you get out? The answer is to strip naked, remove all bits of clothing, and get dry.. even if its sub-zero it MUST be done.. Why? Its because water is 750+ times more dense than air and it transfers heat something like 25 times faster.. This is why its harder to stay warm in cold humid weather than cold dry weather. The water vapor in the air helps remove heat.. it speeds heat transfer and thermal energy always flows from hot to cold, never the other way around.

I don't mean to sound argumentative, but...I am. I've used a heat exchanging mask, and I can confirm that sparing exhaled heat will warm an entire body. I've used the warmest sleeping bag that I can get my hands on, and the fattest air mattress, and covered the mattress and the rest of the floor with a comforter, and I've lied awake at night wishing I weren't cold.

The only way you're going to solve your problem is to get hard core science about it.. all the experimenting in the world won't help you much if you don't understand the science. What seems to work in cold dry air my make things worse in cold humid air, learning about heat transfer and the physics behind it will make all the difference. You may also want to consider some of your own habits.
What are you doing in the hour or two before sleeping? Drinking cold beer or other cold fluids? Drinking hot fluids? Where you physically excreting yourself and sweating? Do you change clothing before sleeping?
Do you wear a ski mask to bed? (I always do if the temperature is below 35F).. Sometimes I'll even wear a mask and a hat on top of it.. You'd be surprised at how much heat goes out your head.

When you're lying in that sleeping bag, if you feel the outside of it with your hand you'll feel no heat coming from the bag. That's because no significant heat is coming from the bag.

Oh that statement is so wrong its not even funny.. Your body is basically a 100 watt heater.. While it varies from person to person, that's about the average. With my big brain, its probably more like 250 watts..
So if you spread out that 100 watts evenly across your sleeping bag, assuming a sleeping bag with a top surface area of 72 inches x 24 inches, that's a total surface of 1728 sqInches of surface area. Divide that 100 watts by 1728 sqInches and your bag will radiate 0.06 watts per square inch... Even in a warm room where the temperature was equalized, your hand would never detect that difference.. Absolutely no chance when its cold.. and yet, that energy loss adds up incredibly fast.
If you're wearing a heat exchanging mask and you put a blanket over your tent to seal off the vents, and if your tent still gets warm inside, where do you think that energy is coming from?

What kind of sleeping bag do you have? Make? Model Number? What are your physical parameters? Age, height, weight?

The surface area of the inside of your lungs is the same as half a tennis court, and the humidity is 100%, and the wind chill factor is never zero. That's going to make a difference.

Yes it is.. but you can combat it if done right.

Yeah, it probably gets more humid inside. It might be a problem.

Its a huge problem.. it might be one of your bigger problems.

I know people keep saying that you can't insulate a tent or the moisture will build up, but I've already done it on an experimental level and it worked fine. Heck, my bedroom is insulated, and I don't wake up each morning in a pool of water.

It doesn't work that way.

Aah, that sounds nice. It's the only way I haven't camped, yet, I think. There never seems to be a yurt when you need one. The closest I ever came to that was a canvas tepee, and it was quite cold. You could almost see your life flying away through that blasted hole in the ceiling.

You should try one.. well worth the cost and will keep the inside of the tent at 60 deg even on a really cold night.

Here are some tips to help you:
Might want to try getting a couple of water bottles for your bed.
http://www.dailyfinance.com/2011/02...d-other-old-fashioned-ways-to-keep-warm-on-t/
These things work great! Get two or three of them and you'll be amazed.

Drink hot fluids before going to bed and make sure your clothing is absolutely dry. When it gets really cold, I wear my Carhart's overall's to bed..

My sleeping bag was a bit over $200 new.. Cheap bags are garbage.. Nothing you buy at a big box retail store is going to be worth anything for cold weather.. even if they say they're good to zero, its just hype. A good cold weather bag is almost always north of $150 to $250.

Another trick I used to do was to provide electric heat.. I made my own heater. Go to any hardware store and buy a low density hot water heater element.. it needs to be the common 240 volt / 2400 watt type. Hook it to a 12 volt car battery and it will get just hot enough so you can't keep your hand on it.. but not so hot it will burn you. I would slide it into a short piece of copper pipe and then wrap it with dish towel and some tape.. Its like having a hot water bottle that never cools off. It will put out about 12 watts of power when hooked to a 12 volt battery.. you'd be surprised at how warm it will keep you.

 

[dusseldorf]

I spent some time investigating four seasons tents and ended up buying a very nice tent that was fairly expensive. I wanted to be able to camp out in the cold, in the snow, in January. The fly was full, and the structure was a freestanding dome, and it had all the features of an ideal tent, I thought, but when I took it out in freezing weather it only measured a 10º F (5.6º C) difference between outdoor and indoor temperatures. That was after being inside it four several hours to warm it up. After looking into it, I discovered that this is about the best that can be expected from the best of tents, except...

Then I discovered the Crua Tri tent, which is about the only tent, anywhere, that actually adds insulation to the walls. It has two downsides, though. Firstly, it was invented almost yesterday, and it has no reviews, anywhere. Secondly, it costs almost $600, which is a lot to invest into a small tent that I know almost nothing about.

Right now, I'm looking into the prospect of making my own tent liner, using a pleated synthetic fabric with polyester fill. Doing anything so unusual to solve such a common problem tends to have its drawbacks, namely that if I've never heard of anyone doing it before, then it probably hasn't worked for anyone.

So, the question to anyone out there is this:

1. What's the greatest temperature difference you've actually measured between the inside and outside of a tent (at night), and the kind of tent?
2. Or, have you ever modified or augmented a tent to make it warmer? Did it work?

Some have argued that it's the sleeping bag, and not the tent that makes all the difference, but the sleeping bag does nothing for inhaled air, which exposes considerable bare surface area to a humid, cold, moving air, and represents a huge loss of heat.

 

[dusseldorf]

There are thermal suits. For the test people spent a week outside in a dug out snow bank.
Made to fit your body specifically.

 

[pescador]

I always camp on the theory that my tent will protect me from the elements and unwanted animals and insects. The key word is protection. I have never thought of my tent as providing warmth. Warmth comes from a combination of heat and insulation. For me, producing warmth comes from body heat and insulation comes from my sleeping bag and/or clothing, never from an external appliance. I have camped in very cold (near zero) conditions on occasion and never felt cold using this approach.

 

[Mudinyeri]

If you want a warm "tent," I would suggest something along these lines.

Like others in this thread, I've camped when it was quite cold. My insulation came from a pad or hammock that kept me off the ground, a good sleeping bag and layered clothing ... not from my tent.