Why Do Tents Get So Hot?

If you've ever spent any time camping in summer, you know that tents can become toasty places in next to no time. But why is this the case? And what can we do to help keep the mercury at a more tolerable level?

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Written by: | Reviewed by: Brian Conghalie
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One of the greatest fears of many newbie campers is freezing to death while out trying to catch their kip in the wilds. In reality, however, most experienced campers know that overheated tents are a far more common problem than underheated ones.

But why is this the case?

Below, we offer a short, straightforward explanation as to why our tents get so hot along with a handful of handy tips to help you keep things cool inside your backcountry crib.

…and if all else fails, you can always check out our guide to the best tent fans.

Daytime Overheating

The main cause of daytime overheating in your tent is simple: the sun…

…or, in technical parlance, solar gain—the increase in thermal energy in any space or structure as a result of it absorbing solar radiation, i.e. sunlight.

In short, tent fabric allows most solar wavelengths to pass through and heat up the inside of your tent. This creates a kind of Greenhouse effect, with heat coming in but having limited means of getting back out.

How to Prevent Daytime Overheating

To avoid your tent turning into a sweltering torture chamber during the daytime, take the following steps:

  • Make use of natural shade from trees and bushes
  • Open all ventilation zips
  • Maximize airflow when pitching your tent by ensuring there is a gap between the tent body and fly
  • Leave the rainfly off if there’s no risk of rain
  • Buy a lighter-colored tent—dark colors absorb more energy from UV radiation
  • Wait until sundown to pitch your tent
  • Suspend a tarp above your tent to provide shade instead of using a rainfly

Nighttime Overheating

The main source of nighttime overheating is not anything outside your tent but, rather, what’s inside it: humans.

We humans naturally heat our bodies to an average temperature of 98.6° Fahrenheit, which is normally much warmer than the temperature of the ambient air that surrounds us. While outside temps cool down as the day progresses, our body heat and the warm air from our breathing essentially cancel out that decrease in temperature and can leave things a little bit stuffy inside our tent without adequate ventilation.

How to Avoid Nighttime Overheating

The first step to ensuring your tent isn’t intolerably toasty in the evening is to make sure it is well-ventilated in the evening. On particularly hot days, the sun can heat up the inside and contents of your tent, and the stored heat or “thermal mass” will release slowly after sundown.

Other tips that can help reduce nighttime overheating include:

  • Ditch the rainfly if the skies are clear and forecasts are good
  • Opt for a larger tent—smaller tents maximize thermal efficiency; big ones do the opposite
  • Store your gear outside your tent so your body heat is dispersed throughout more cubic footage

Other Tips for Staying Cool in Your Tent

1. Pitch your tent near a river or lake to take advantage of the cooler air.

2. Take a dip before bedtime to lower your core temperature.

3. Reflect heat away from your tent by laying reflective thermal survival blankets on the tent wall most exposed to the sun.

4. Bring along a camping cooler if car camping or not venturing too far from the roadside.

5. If backcountry camping, hike into higher ground—where temps will be lower—before pitching your tent.

Why do Tents Get So Hot? Wrapping It Up

Tents can overheat for various reasons, but in most cases they do so due to the ‘greenhouse effect’ caused by sunlight penetrating their diaphonous walls. If you’re keen to beat the heat, park you tent in the shade cast by natural landscape features, throw a tarp or thermal blanket over the side of your tent, and open all vents and doors to make sure there’s plenty of airflow!

Last update on 2023-05-29 / Affiliate links / Images from Amazon Product Advertising API

Kieran Avatar

Kieran James Cunningham is a climber, mountaineer, and author who divides his time between the Italian Alps, the US, and his native Scotland.

He has climbed a handful of 6000ers in the Himalayas, 4000ers in the Alps, 14ers in the US, and loves nothing more than a good long-distance wander in the wilderness. He climbs when he should be writing, writes when he should be sleeping, has fun always.

Kieran has taught mountaineering, ice climbing, and single-pitch and multi-pitch rock climbing in a variety of contexts over the years and has led trekking and mountaineering expeditions in the Alps, Rockies, and UK. He is currently working towards qualifying as a Mountaineering and Climbing Instructor and International Mountain Leader.

Kieran’s book Climbing the Walls—an exploration of the mental health benefits of climbing, mountaineering, and the great outdoors—is scheduled for release by Simon & Schuster in April 2021.

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