What a sleeping pad does
A sleeping bag keeps you warm only where it is lofted. Underneath you, the insulation is squashed flat, so the cold ground pulls heat out of your body all night. A sleeping pad solves that problem by putting insulation between you and the ground, and by cushioning you from rocks and roots. In cold weather, the pad is often more important than the bag.
Types of pads and mattresses
| Type | How it works | Strengths | Watch out for |
|---|---|---|---|
| Closed-cell foam | Dense foam that does not absorb water, often folded or rolled | Cheap, light, nearly indestructible, works as a backup | Bulky; firm; usually low to medium R-value |
| Self-inflating | Open-cell foam sealed in a shell that expands when the valve is opened | Easy to use; good comfort; decent insulation | Heavier and bulkier than air pads; can lose loft with age |
| Air pad (inflatable) | Chambers of air, sometimes with insulation inside | Lightest and smallest packed; thick and comfortable | Can puncture; may be noisy; needs inflating |
| Insulated air pad | Air pad with foam, reflective layers or synthetic fill | Higher R-values for cold weather | Cost; weight; more complex |
| Air mattress | Large, thick, usually for car camping | Roomy; familiar feel | Heavy; needs a pump; cold air circulating inside can chill you |
| Camp cot | Raised fabric bed on a frame | Gets you off the ground; good for rough terrain | Cold air flows underneath; needs insulation on top |
Many experienced campers use a combination: a closed-cell foam pad under an air pad, which adds insulation, protects against punctures and provides a backup.
Understanding R-value
R-value measures a pad's resistance to heat flow, so a higher number means more insulation. Most pads are tested to the ASTM F3340 standard, which was developed so that ratings from different manufacturers can be compared. Common guidelines are:
- Summer: about R1 to 3
- Three-season: about R3 to 5
- Winter: R5 and higher
These are guidelines, not guarantees. How warm you feel depends on your sleeping bag, your clothes, your food, the wind and your own body. Use our sleeping pad R-value picker for a quick estimate, and read the sleep system guide for how the pieces fit together. If you stack two pads, their R-values roughly add.
Size, shape and thickness
- Length. A "regular" pad is commonly around 72 inches, and a "long" pad around 77 to 78 inches. If you are taller than about 6 feet, check the length. Some people cut costs and weight with a torso-length pad, using a pack or rope under the feet.
- Width. Many standard pads are about 20 inches wide, while wide versions are around 25 inches. If you sleep on your side, roll a lot or share the tent, wide is worth the extra weight.
- Thickness. Thicker is not always warmer, because a thick air pad with no insulation can feel cold. Thickness mostly adds comfort, particularly for side sleepers on hard ground.
- Shape. Rectangular pads use space well. Mummy-shaped pads are lighter. Tapered pads save weight, but your feet and elbows may hang off.
Always check the dimensions on the label. Makers use different names for the same sizes.
Comfort, noise and stability
Some air pads crinkle when you move, and some have a springy feel that can roll you off. Look for baffle designs that keep you stable and a top fabric that is quiet and does not slide on your sleeping bag. If your pad is slippery, a sleeping bag with a non-slip bottom or a thin grippy mat under the pad can help.
Inflating and deflating
Blowing into a pad adds moisture, which can lead to mildew over time and, in freezing weather, can freeze inside. Many pads come with a pump sack, and small electric pumps are sold separately. Do not overinflate, and let a little air out if the pad feels like a drum. When deflating, open the valve and roll or fold from the far end, pushing the air out. Do not force it.
Finding and fixing leaks
- Inflate the pad fully and listen. A hiss can lead you to a leak.
- Check with soapy water. Brush or spray a mix of mild soap and water over the pad and look for bubbles. Check the valve and seams too.
- Mark the hole, dry the pad and apply the maker's patch following the instructions.
- Retest overnight. Slow leaks may take hours to show.
A small repair kit weighs very little. Carry one on every trip that uses an air pad.
Care and storage
- Keep it clean. Wipe with mild soap and water, and rinse. Avoid harsh cleaners.
- Dry fully before storing, with the valve open.
- Store unrolled or loosely rolled, in a cool, dry place. Long-term compression can damage insulation and foam.
- Protect from sharp objects and heat. Use a ground cloth or a footprint under your tent, and do not leave pads in a hot car.
- Do not use in a campfire environment. Synthetic pads melt.
Common mistakes
- Choosing by thickness alone. R-value measures warmth, not thickness.
- Skipping the repair kit.
- Ignoring size. A pad that is too short or narrow ruins sleep.
- Storing it compressed for months.
- Putting an air mattress on cold ground and expecting warmth. Air mattresses can be cold without insulation.
Frequently asked questions
What R-value do I need?
Common guidelines are R1 to 3 for summer, R3 to 5 for three seasons and R5 or more for winter. Adjust for how you sleep and how cold the ground is.
Are self-inflating pads still worth buying?
Yes. They are simple, comfortable and durable, but heavier and bulkier than most air pads.
Can I stack two pads?
Yes. The R-values roughly add, and a foam pad under an air pad protects it and gives you a backup.
How do I find a leak?
Inflate it, then brush soapy water over the surface and watch for bubbles.
Do I need a pad if I have a cot?
Yes, in cool weather. Cold air circulates under a cot, so you still need insulation between you and the fabric.
