When I got my first Nalgene Bottle, I filled it with ice cold water and hit the climbing gym.
About an hour in, I was shocked to find the bottle soaking wet, so bad it left a small circular puddle when I picked it up for a sip. It wasn't leaking, it was just sweating A LOT.
Over time I've learned using ice in my Nalgene causes it to sweat even more. Knowing exactly why Nalgene bottles sweat can help you to prevent it, which is great for when I have it on my desk at work and I don't want it wetting and ruining my papers.
Nalgene Bottles sweat due to condensation. Cold water in the bottle causes water vapor in the air to be converted into a liquid that clings to the bottle. To stop your Nalgene bottle from sweating, use an insulating sleeve that will limit condensation and absorb any that does occur.
I found an insulating neoprene sleeve for a few bucks on Amazon, and haven’t had any issue since. It also has the added benefits of keeping the water in my Nalgene colder for longer, making it a worthy investment.
Why Do Nalgene Bottles Sweat?
We all know that when a bottle sweats, it’s not the water in the bottle leaking out. But it’s less well known where those little beads of water are really coming from and why they make your bottle sweat so much and become so wet.
Are they just appearing out of thin air?
Well, yeah actually. Sort of.
What you’re seeing is a process called condensation.
You may have noticed that your bottle sweats more when it’s particularly hot and humid outside and your bottle is particularly cold — the exact conditions needed for condensation to occur.
I have personally noticed that when I put ice cubes in my Nalgene (so my water stays cold for longer) it’ll sweat A LOT more than if I just use water out of the fridge. Also, when the water in my bottle warms up to room temperature the sweating usually stops.
The air around you always contains some amount of water vapor. Like how clouds contain water vapor that can turn into rain the air around you contains water in its gas form, you just can’t see it.
Because Nalgene bottles aren't insulated the cold water in your bottle causes the outside of the bottle to become cold to touch.
When the cold surface of your bottle cools the surrounding air below its dew point, some of the surrounding water vapor in the air is converted back to liquid water — which is what you see clinging to your bottle.
The warmer and more humid the air is the more likely you are to get condensation and sweating on your bottle.
Also, the colder the water in your Nalgene the more sweating you’ll get. This is because the colder the outside of the bottle the faster it’ll turn at water vapor into liquid which clings to your bottle.
This is also why when you have room temperature water in your Nalgene you don’t get any sweating anymore. The plastic walls of the water bottle aren’t cold anymore so the process of turning water vapor into a liquid stops.
How To Stop Your Nalgene Bottle From Sweating
If you want to prevent your Nalgene Bottle from sweating, you have two options.
For starters, you could simply drink room temperature water. When the contents of your bottle are of a similar temperature to the surrounding air, condensation is unable to occur.
But seriously…who wants to drink room temperature water if they can avoid it? Nothing beats ice cold water on a hot sunny day at the beach, out on a bushwalk or climbing at the crag.
If you prefer ice cold water like I do your best bet is to use an insulating sleeve, like this fun patterned neoprene sleeve by Sok It.
For a cheaper insulating sleeve for your bottle check out this insulating Nalgene sleeve made by the brand itself (at Amazon).
This handy neoprene sleeve fits perfectly onto any 32 oz Nalgene bottle and helps to keep your drinks colder longer and will reduce sweating. Features a draw string for a tight fit and a side clip for easy carrying.
By insulating your bottle, it’s less likely to cool the surrounding air below its dew point to allow condensation.
Any condensation that still occurs (no sleeve is able to completely prevent it) will be absorbed by the sleeve and kept off your hands, desk, cupholder, or gym floor.
It also has the added benefit of keeping water cold longer in your Nalgene bottle AND making your Nalgene easier to carry.
Do Metal Nalgene Bottles Sweat?
For those who don't like plastic Nalgene also makes stainless steel bottles. Do these stainless steel Nalgene bottle sweat like the plastic ones or are they sweat-free?
Nalgene stainless steel bottles are non-insulated and so will sweat just like the plastic Nalgene bottles. In fact, the stainless steel bottles are likely to sweat MORE than the plastic bottles because stainless steel conducts heat better.
If you want a sweat-free bottle then you need to get a double-walled vacuum-insulated stainless steel bottle. Currently Nalgene doesn't sell any vacuum insulated bottles.
The Best Alternative To Nalgene Bottles That Doesn’t Sweat
Sweating, or condensation, isn’t a problem exclusive to Nalgene bottles. It’s an issue with any non-insulated bottle, cup, tumbler, or mug filled with cold liquid.
As long as the temperature of the container cools the surrounding air below its dew point, sweating will occur.
If that’s a dealbreaker, and you don’t want to use an insulating sleeve to manage the issue, a Nalgene bottle may not be the best fit for you.
Instead, you'll need to invest in a vacuum-insulated stainless steel bottle like Hydro Flask, Yeti or any other reputable brand.
For a cheaper option, Simple Modern Water Bottles share many of the same benefits of Nalgene Bottles, but are insulated to prevent sweating.
They come in a 32 oz size, the same as the standard Nalgene Bottle, and only cost a few dollars more (unlike some premium insulated bottles that may cost two to three times as much).
And because they’re made of vacuum-insulated stainless steel instead of plastic, your water will be kept ice cold for up to 24 hours while the exterior of the bottle remains at a neutral temperature — and won’t sweat no matter how hot and humid it is outside.
Regardless of sweating, Nalgene Bottles are some of my favorite water bottles (and I have more than I care to admit). They’re lightweight, durable, easy to clean, eco-friendly, affordable, and help me reach my water intake goals.
My friends at the climbing gym all swear by them, and ever since I got my own, I certainly see why.
Made with BPA-free Tritan Renew plastic these Nalgene bottles are made with 50% recycled plastic.
This is the best selling water bottle that has been around for 30 years (and likely to last you 30 years). Suitable for warm and cold beverages (-40 to 212ºF) this is marked with milliliters and ounces for easy measurement.
- Nalgene bottles sweat due to a process called condensation, where water vapor is converted back to liquid water as the air surrounding your bottle is cooled.
- To prevent your Nalgene bottle from sweating, switch to room temperature water or use an insulating sleeve.
- If you want a bottle that won’t sweat, any well-insulated bottle should do the trick.