Tent temperature

“I spent a cold Friday night on Mt. Rogers last weekend. At 3 am the outside temp. was 9 degrees outside the tent and 25 degrees inside the tent (two man zipped up tight). My questions are: How much warmth does a tent add to your sleeping bag? And: If I had used a tarp, would I have noticed the difference since the tent holds moisture from breathing (at 9 deg.)?”

“BS when we were at Linville last year I think the outside temp was around 24 degrees yet a distinctly remember inside my tent was 38 when I got in and went up to about 42 after I was in it for awhile.”

“Was it..................in the Sun???
I get stuck on concepts like thermo-equalibrium, etc...”

“Nope no sun it was rainy and gloomy!”

“Tent is warmer than a open trap for sure.
I think it would depend on the size of the tent and the type of tent, the number of bodies in it to figure out how much warmth it holds in among other factors like relative humidity, tent location.

I vent mine, because the walls aren't screened just the doors and a small one one in the top.”

“Inconceivable!!! LOL”

“The tent has very little insulating value and if it is vented properly the air will be changing frequently. If it is warm it is because there is a heat source putting heat into the tent faster than the heat can move out. To heat up a tent increase the heat source or slow the heat lose or both. Its that simple. Ask my Hubby, I know how to heat up a tent.”

“I bet you do mtn gal! LOL

My tent is the Vaude Quest and the rainfly cover the entire tent all the way to the ground. It is actually set up to be used by itself iffin ya want a tarp type set up. The inside is mainly just mesh. Thats the reason it is so toasty. No vetalation unless I want it.”

“If the ground is considerably warmer than the night air temperature then you've got one nice heat source. I'm talking only 20F or so here which is conceiveable if you pick your site well. Cut down on the ventilation and use a full cover fly and your tent should stay warmer than the outside air temp by 5 to 15 F.

If the ground is actually colder than the ambient air then expect the opposite.”

“Yes, I agree with mtn. gal about a tent having little insulating value. However, a tent tends to hold some heat. My SD Clip Flashlight (rainfly very close to the ground) tends to stay about 10-15 degrees warmer than the outside temp., especially if there is little wind. Like mtn. gal said, it has to do with more heat output inside the tent than the outside temp. and air circulation can take away.”

“The "rule of thumb" I learned and have used is that a tent will add about 10 degrees to your sleeping bag rating. I have found that to be true in my case.”

“I'll go along with the tent adding 10 to 15 degrees. It definitely helped with the 20+ mph winds on Friday night.


Do any of you tarp users sleep under just a tarp in single digit or less temperatures?


And what about staying in the AT shelters? Last couple of times in a shelter with the temp in the low teens, I 'bout froze.”

“Around here if it's single digit or less and not a lot of snow in the forecast, we don't need the tarp!”

“Yea, Le Subtil, and you are carrying a little more that a 2.5 lb. - 35 degree sleeping bag too!”

“True, a tent may only provide 10 degrees or so, but it also eliminates wind chill, so that can be another 30 degrees or so (relative).”

“Uh... thats a +35 deg. bag.

The tent definitely helped with the wind.”

“Moist air holds much more heat energy than dry air. A 4-season air-tight tent tends to keep moisture from escaping, and therefore holds more of the heat given off by the occupant(s). Plus, there is no windchill factor within the tent, which occurs with a 3-season tent when it is used in cold windy situations.

I don't think the tent really adds to the sleeping bags warmth. Just that the winter tent is a shelter to keep out the frigid wind and hold what heat is generated within during the night.”

“But how does it rain when its 24 degrees???”

“LOL!!!!

gojo, we all were wondering the same thing. it was really bizarre and reeeally chilly.”

“sorry, i meant...


LOL!!!!

flyguy6x, we all were wondering the same thing. it was really bizarre and reeeally chilly.”

“I'd say its a strange world we live in! Certainly if'n it can snow at 38 degrees, its possible to rain at 24. Also the forest floor decomposing and heat trapped in the earth could account for temps in excess of air temp. I was being a doubting Thomas.
Thanks, Rad, for not calling me Sarabelle!
Sounds like the makings of a new thread "STRANGE PHENOMENA on the trail"”

“I have noticed a 10 or 15 degree increase in temperature inside a tent. I've slept out under the stars in the winter and a tent seems a lot warmer especially if there's any wind.”

“I should clarify my earlier post - I agree a tent will most certainly be warmer; that's common sense. I do like to sleep under the stars whenever possible, so if there are no bugs, or precipitation, and not much wind, I'll sleep out in the open. I wake up a lot and then I can just open my eyes and look at the skies as long as I like...”

“I been in a tent at around -10, with a wind chill another -25. The inside did get up to 0, but that was with three guys and two stoves going. Can't say is something I would go out and plan but it is fun to look back at.

Also, been out on the snow down to around 0, used a bivy and a dam good bag, it is nice untill you have to pee.”

“No one mentioned radiant heat loss to deep space on a clear night. Even a tarp would help minimize this. It is possible to freeze water at temps above freezing using deep space radiant heat loss. Our forefathers did it all the time.”

“Ever notice how much difference a candle lantern makes in a tent? Just a thought. H.T.”

“I can say that a tarp serves no protection from the cold. Just wind.”