Sleeping pads insulate the same way that sleeping bags and clothing layers do. They trap and hold a layer of "dead" (non-circulating) air between your body and the cold (in this case, the cold ground). Your body gradually warms this layer of dead air and it becomes an insulating barrier.
Beneath you, though, a sleeping bag's heat-trapping loft gets compressed to almost nothing due to the weight of your body. As a result, you need a pad to buffer you from heat-depleting contact with the cold ground (this is known as "conductive" heat loss). The insulative performance of a pad depends upon how much air it holds inside and how free that air is to circulate.
These pads use air for cushioning and must be manually inflated. Some models integrate foam, insulative fill or reflective materials to increase warmth.
Pros: Comfortable and lightweight. Fine for backpacking or camping in warm conditions; insulated models can be used year-round.
Cons: Can puncture, though field repairs are not difficult. Noninsulated models offer poor insulation due to free circulation of air inside.
Shop REI's selection of air pads.
Pioneered by Therm-a-Rest® pads, these offer a combination of open-cell foam insulation and air. Open the pad's valve and air fills the vaccuum. These pads are wrapped in air-tight, waterproof nylon shells. Popular with backpackers, a few of the thickest models are better suited for car campers.
Pros: Comfortable; excellent insulation; firmness is adjustable; very compact when rolled up.
Cons: Heavier than simple foam pads and more expensive. Can be punctured or ripped, though field repairs are not difficult.
Shop REI's selection of self-inflating sleeping pads.
These basic backpacking pads feature dense foam filled with tiny closed air cells.
Pros: Lightweight, inexpensive and durable; excellent insulators; won't absorb water.
Cons: Less comfortable. Relatively stiff and firm, so they tend to be bulky.
Shop REI's selection of foam pads.
These car-camping mattresses use air for comfort and are much thicker than foam pads. They are as close to a real bed as you can get and are usually sized to take regular sheets.
Pros: Very comfortable. Easy and quick to inflate with a pump. Suitable for car or boat camping, or as a guest bed at home.
Cons: Relatively heavy and bulky. Pump required for proper inflation. Can puncture or leak. No insulation; for mild conditions only.
Shop REI's selection of air mattresses.
Your pad decision can be narrowed quickly by considering your type of travel.
Length: At a minimum, your shoulders and hips need to fit on a pad. Regular (typically 72" long) and long (from 75" to 78") pads will insulate your legs and feet—a big plus on chilly fall and winter trips. A short or 3/4-length pad (usually 47" or 48") weighs less and packs smaller.
Width: Nearly every pad offers a standard width of 20". If you tend to roll around a lot, you may want a width of 25" or 30" that's found in some large sizes. Tapered designs reduce volume a bit and pack smaller.
Women's pads: These pads are shorter (66" is typical), with added insulation at the hips and feet where women need it most.
R-value: Insulation is measured according to its capacity to resist (that's the "R") heat flow. The higher a pad's R-value, the better you can expect it to insulate you from cold surfaces. The R-values shown on REI.com product pages are provided by the manufacturers and range from 1.0 (minimally insulated) to 9.5 (well insulated). Thicker pads generally offer higher R-values.
Eco-friendly pads: A growing trend is pads made with recycled foam or shell-fabric materials.
Sleeping pads come in a variety of styles, shapes and lengths. If possible, visit your nearest REI store to try out a few different pads before deciding on a single model. This will help you get a feel for:
Finally, consider any additional pad features. These include multiple air chambers (for a custom adjustment), built-in pillows (for comfort), textured pad surfaces (for better insulation, less slip and more comfort) and tapered pad shapes (for less weight and bulk).
By Steve Tischler
Read Author Bio
Last updated: 09/03/2013
In This Article
How are we doing? Give us feedback on this page.