Frequently Asked Questions
Choosing a Mattress
How do I choose a mattress?
Begin choosing a mattress by going to the home page and choose the series that's right for you.
When buying a mattress, how should I compare comfort versus weight?
Shoot for a mattress that’s comfortable but within your goal for weight. Comfort and weight are trade-offs, as the thickest mattresses are often the heaviest. Minimalists and those taking long trips generally opt for the lightest mattress possible. Our lightest self-inflating mattresses require extra care to prevent punctures, so if you spend a lot of time bushwhacking you should consider a Z-Lite™ or RidgeRest® closed-cell pad as a puncture-proof alternative.
Which closed-cell pad is more comfortable—a RidgeRest or a Z-Lite, and why?
Our Z-Lite pad is slightly more compliant due to the materials used and the shape into which it is molded. It also folds into a smaller volume. The trade-off is that RidgeRest is slightly warmer.
What type of user should consider the Fast & Light™ series?
These mattresses are engineered for users who will be carrying their mattress, and consider mobility and packability slightly more important than durability and comfort. Fast & Light mattresses are durable and comfortable, but our Trek & Travel mattresses are slightly more durable and comfortable, with only a minor increase in weight.
How do I determine the best mattress width for me?
The mattress you select should be wide enough that your torso does not hang over the edges. This is a matter of individual comfort, so lie on the mattress you’re going to buy to make sure it’s a comfortable width. Our mattresses come in 20", 25", and 30" widths.
What are “R-values”?
R-values are a measure of insulation and are based on a mattress being fully inflated. The higher the value, the warmer you will sleep. For a higher R-value, fully inflate your mattress.
If I buy a ProLite 3, will it be warm enough on the snow?
No. The ProLite 3 is recommended for three-season use. Some people sleep colder than others, and many snow camping pros prefer to sleep with a RidgeRest or Z-Lite under their self-inflating mattress for increased warmth. If you sleep particularly cold, we recommend the combination of a closed-cell and self inflating mattress for extra protection. See Pro Tips for more snow camping ideas.
Are there CFCs in Therm-a-Rest mattresses?
Therm-a-Rest has not used CFC’s for more than a decade. We have not used chlorinated hydrocarbons for at least four years.
Why don't you sew accessory straps to the ends of the mattresses?
Because the fabric is so heavily coated, stitching causes a perforation and a likely path for the sewn-on strap to rip off and damage the mattress.
Why not offer repair kits or stuff sacks as standard features on your mattresses?
Not all users want these. Rather than increase the cost and weight of every mattress, we decided to let users decide which accessories made sense for their applications.
What type of user should consider the Ambush™ mattress?
Our Ambush hunting mattress, like the ToughSkin™ in our outdoor line, is designed to be extra-rugged, making it ideal for everything from overnights in the backcountry to bugling elk and lying in comfort while blind hunting. Its multilayer construction—featuring an air-holding seal sandwiched between a top layer of open-cell foam and a bottom layer of closed-cell foam—prevents punctures from thorns and sharp rocks, and, in the unlikely event of a puncture, continues to provide backup warmth, comfort, and performance, with the same R-value (2.3) as a RidgeRest®.
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Care and General Use
How do Therm-a-Rest mattresses self-inflate?
When you open the valve, the open-celled foam responds by soaking up air, similar to a sponge absorbing liquid. Self-inflation is what makes Therm-a-Rest mattresses easy to use and comfortable. Once the mattress has inflated, you can adjust the firmness by adding or letting air out. It's that simple.
What is the best way to store my mattress when it is not being used?
Store your mattress unrolled and with the valve open. Because the mattress foam tends to “remember” the shape it holds most, your mattress will self-inflate faster if stored unrolled. Also, store your mattress dry. It will dry quickly with exposure to the air. If a mattress is left damp, mildew may damage the cover’s air-holding urethane. Many people store their pads under a bed or behind a door.
Can I blow into a mattress if I am sleeping on snow?
Yes. Doing so will increase the loft of the pad as well as its warmth.
What about moisture buildup in the mattress when I blow into it?
If you let your mattress self-inflate for a while and then add only a few puffs of air, you don’t have to worry about moisture buildup. Even in winter, freezing of moisture in the pad isn’t an issue unless you are doing this daily for months at a time.
Can I ever get my mattress back to the same rolled size as when I bought it?
Option1: Fold the mattress several times and sit on it to get most of the air out, then start at the end and roll toward the valve, using your knee as pressure to keep it rolling tightly.
Option 2: Fold mattress in half lengthwise, then fold again. Now sit on mattress and open the valve. When all the air is out, close the valve and roll up your mattress.
What side of the mattress do I sleep on?
The side of the mattress with the logo and serial number will most often be made of our nonslip fabric—this is the “top.” The fabric greatly increases friction between your Therm-a-Rest and a slippery sleeping bag, so you stay put on your mattress all night long.
What is the best way to insert a mattress into a chair kit?
Mattresses insert into chair kits more easily if they are only partially inflated instead of fully inflated or fully deflated. Note the location of the valve access hole in your Therm-a-Rest chair kit and insert your mattress so that the valve is accessible. Please note that chair stays are often put in the wrong way.
What is the best way to store a RidgeRest pad?
Store your RidgeRest flat or loosely rolled. Don’t use rubber bands to hold it rolled, as they deform closed-cell foam pads.
When carrying the RidgeRest on the outside of the pack how does it do in rain? A downpour? Do you need to use a pack cover or tote sack with the RidgeRest closed cell?
Due to RidgeRest’s use of closed-cell XLPE foam it will NOT absorb water even in a downpour. You can give your pad a good shake when setting up camp and remove any surface water. The only reason to cover a closed cell pad is to protect it from brush and branches tearing it up while you are hiking.
Is it OK to leave my mattress inflated in my car or tent?
No. Don’t leave your mattress inflated in your car or tent on a hot day! The air trapped in the mattress will expand, and the heat can lead to fabric delamination or a burst pad and will not be covered by your warranty. You don’t have to roll it up as long as the valve is left open.
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Repair and Maintenance
My mattress has a slow leak. How can I find it?
1) Inflate mattress as much as possible and close valve off.
2) Fold pad in half or thirds to increase pressure.
3) Immerse the mattress in water.
4) Look for a stream of small, escaping bubbles (the source of the leak) and mark it with a piece of electrical tape.
5) You are now ready to make your repair.
My mattress developed a leak after just one use.
We test all mattresses before they leave our factory in Seattle, but there are a number of ways they can be damaged during shipping, in a retail store, or even after only one use. It doesn’t take a huge puncture to cause a pad to deflate overnight, and some areas like the American Southwest are covered in prickers. Call us at 1-800-531-9531 to arrange an RA #, so we can repair your mattress, or find the leak (see above) and repair it yourself.
My mattress has a metal valve and I want to replace it with a plastic one, but it doesn’t look like the plastic valve will fit.
The diameter of the ends of the metal and plastic valves that fit into the plastic wedge-shaped vent tube is the same. Only the cap on the plastic valve is larger.
When repairing my Therm-a-Rest, do I always have to use HotBond™?
That depends on the size of the leak. HotBond needs to be used with a patch; tests have proven that HotBond alone will not stop a leak. If you have a small leak that does not require a patch, a urethane-based glue should be used. Some popular brands are SeamGrip, SeamSeal, AquaSeal, and the glue that comes with a bicycle repair kit. These all work well. Allow 24 hours for drying.
What is the best way to clean my mattress if it gets really dirty?
DO NOT put your mattress in the washing machine. A quick scrubbing with Formula 409 or a household cleaner is best. Use soap and water in the field. Remember to close the valve while washing.
What if I puncture my mattress out in the field and don’t have a repair kit?
Duct tape will do for a temporary repair, but its sticky residue sets over time and can make a permanent repair virtually impossible. A bicycle tube repair kit or self-adhesive ripstop nylon repair tape, normally used to repair parkas or tent flies, is better. You can also use a piece of urethane-coated nylon over the tear with a urethane-based adhesive such as Urebond, AquaSeal, or SeamGrip.
Is there a special way to store my mattress when carrying it outside my pack?
Store your mattress in one of our stuff sacks when carrying it on the outside of your pack. We get a lot of mattresses back that have been scraped on the edges by branches and bushes.
How can I be sure that my mattress is holding air?
Roll all the air out of your mattress and close the valve tight. The mattress should stay in the rolled-up position.
What do I do if water gets inside my mattress?
Roll the mattress up to force the water out of the open valve. If there is a lot of water, you may have to do this several times. Hang the mattress upside down with the valve open in a warm dry place. It will take about three days for the mattress to dry out.
How do I repair my mattress?
Download Instructions for Mattress Repair
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Pro Tips
Which mattress or combination of mattresses do you recommend for snow camping?
Many experienced mountaineers and cold-climate adventurers find that using a ProLite 3 or 4 mattress in conjunction with a RidgeRest or Z-Lite pad is a great way to increase warmth without the bulk or weight of a single large mattress. This combo also offers extra puncture protection for your self-inflating mattress. If you were to choose a single mattress for cold weather usage, it should be the Trail Comfort™, which is designed to deliver our best combination of comfort, warmth, and weight. One final snow camping tip: Try over-inflating your mattress with a few extra breaths of air. Your mattress will be a bit more firm, but the added air will increase the foam’s loft for extra insulation.
Using a Therm-a-Rest self-inflating mattress for back support in a rucksack:
When using your self-inflating Therm-a-Rest pad in a rucksack to increase back support you should roll the pad up completely and store it against your pack with the valve up (and closed) while you put in the rest of your items. You can then open the valve, and the mattress will expand to secure items in your pack, giving you more back support when you are hiking.
Medical evacuations:
In an evacuation, many rescue pros use their Therm-a-Rest mattress to insulate an improvised litter to help stave off hypothermia and to increase comfort.
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