How to Manage Condensation in Your Tent

We’ve been there – you wake up in your tent in the morning and everything’s damp or there’s moisture accumulating on the groundsheet. The first thought that might pass through your mind is that there’s a leak, but there’s another culprit that you’re much more likely to encounter. Condensation.

Unless you can change how physics works, tents accumulate condensation. From your basic weekend camping tent through to high end technical tents, none are immune – some may be better or worse, but none are exempt. The good news is there are some simple steps that you can take to minimize the problem, though.

The first thing to understand is what condensation is and where it comes from. The air around us holds moisture – warm air can hold more moisture, cool air less. If you have warm air meeting a cooler environment, the moisture condenses out and forms tiny water droplets (breathing out clouds on a frosty morning or the moisture on a cold glass on a hot day are good examples). In camping terms, when the warm air inside your tent makes contact with the cool surface of your tent fabric overnight or in cold, wet weather, the moisture in the air condenses and forms water droplets. If this happens enough, you and your gear can get damp and means that condensation is worse in a single walled tent than an inner tent and flysheet setup.

Where did all that moisture come from? A lot can be in the air anyway in the form of humidity, but a good amount comes from us being inside the tent. Over the course of a night, the moisture in your breath can be around 500ml (estimates do vary) – by the time you have two, three or more people in a tent, that’s a lot of water! If you then add in wet gear, steaming cups or even a pet dog, you can quickly have a big problem.

So now we know where condensation comes from, how do we manage it?

1 Ventilation, Ventilation, Ventilation

A well ventilated tent has good air flow between inside and outside which reduces the accumulation of humidity (moisture). Leave any air vents in your tent open and if weather conditions allow, try to leave door and window panels slightly open (make sure they are bug mesh protected). During the day, open as many door, window and other flysheet roll backs as possible without allowing bug entry to relieve humidity built up overnight. It is still important to make sure that your tent is well ventilated on cold nights, even though that seems counterintuitive. A good sleeping bag will keep you warm if the air in your tent is a little cooler than it might be with the vents shut, a damp sleeping bag from excess condensation won’t!

2 Pitch Your Tent Correctly

If your tent has a separate inner tent and flysheet (lots do), make sure that the flysheet is properly set up and not touching the inner tent. The inner on most tents is breathable allowing moist air to exit, this moist air makes contact with the waterproof flysheet, condenses and will then usually run off following the curvature of the tent. If the flysheet contacts the inner tent, the flow will be interrupted and things get wet. The same goes for tent fabric that needs tensioning – avoid sagging sections where the condensed water can run off inappropriately.

3 Pick the Right Location

Pitching your tent in a tucked away, sheltered area may seem ideal, but in condensation terms it’s not good. Pitch your tent where it can catch a natural breeze to aid ventilation and avoid pitching in hollows where colder air may accumulate on cool nights. Don’t pitch up too close to water – dams and rivers look beautiful right next to your tent but you’ll also find additional moisture in the air, so pick a spot further back than the bank edge. Also, this one is common sense, avoid overly wet ground when pitching your tent.

4 Don’t Add More Moisture Than Necessary

Your tent is not the place to be drying wet gear – keep wet towels, swimwear and laundry outside on a line. If you’ve got wet clothes after a downpour, keep a dry set handy to change into and hang your wet gear outside when you can. If you’re camping with man’s best friend, towel off soggy doggies before they come in!

5 Cooking is an Outdoor Activity

You shouldn’t be cooking in your tent anyway – flames and fabric are a really bad combination from a health and safety perspective. In terms of condensation, though, steaming pots are a nightmare and you don’t need all that additional moisture in your tent.

If you are in a situation where condensation does get out of control and your tent does get excessively wet inside, then use a compact camp towel to dry surfaces off where you can. It may be worth considering taking off your flysheet if the next day is sunny and leaving the inside of the fly to dry in the sun (this one won’t work easily for large family tents – leave as many doors and windows open as you can). If you do still suspect that your tent is leaking in wet weather, then check out how to leak test your tent.

©CAMPCRAFT