Quick Answer

For most three-season camping, an R-value of 4 to 5 keeps you warm down to about 20°F. If you sleep cold or camp in winter, aim for R-value 6 or higher. The HEST Dually Custom S is designed for comfort in a camper van, but its exact R-value isn't published—so plan your insulation layers accordingly.

Why R-Value Matters More Than Thickness

R-value measures how well a material resists heat flow. The higher the number, the better it insulates you from the cold ground. Thickness alone doesn't tell you how warm you'll be—a thick pad with low R-value can still leave you chilly. That's why checking R-value is more reliable than just looking at loft.

How to Match R-Value to Your Trip

Your ideal R-value depends on the season, your sleeping bag, and whether you tend to sleep cold. A summer pad with R-value 2 might be fine in July, but it won't cut it for shoulder-season nights. For most camping from spring through fall, an R-value of 4 to 5 is a safe middle ground. Winter campers should look for R-value 6 or higher, especially if you sleep on snow or frozen ground.

The Trade-Off: Insulation vs. Packability

Higher R-value often means more material, which can add weight and bulk. But a custom camping mattress like the HEST Dually Custom S prioritizes comfort and space in a van, not ultralight backpacking. If you're car camping or van camping, the extra weight is less of a concern, and you can focus on warmth and comfort instead.

R-Value FAQ

What is a good R-value for a camping mattress?

For three-season camping, look for R-value 4 to 5. For winter or cold-sleepers, choose R-value 6 or higher. If you're unsure, err on the warmer side—you can always vent. When in doubt, go higher R-value for comfort.

How do I choose R-value for camping?

Match R-value to the lowest expected temperature. A simple rule: R-value 2 for summer, 4-5 for spring/fall, and 6+ for winter. Also consider your sleeping bag's rating and whether you sleep cold. Check the forecast and your sleep style before buying.

What R-value does the HEST Dually Custom S have?

HEST doesn't publish an R-value for the Dually Custom S. It uses temperature resilient memory foam, which helps with comfort and heat retention, but for winter camping you should add an insulating layer or use a warmer sleeping bag. If you plan to camp in cold weather, ask the manufacturer or test the pad yourself.

Can I increase the R-value of my camping mattress?

Yes. Add a closed-cell foam pad underneath or a down blanket on top. This boosts insulation and protects against punctures. It's a simple way to extend your mattress into colder seasons. Layering is a budget-friendly way to boost warmth.

Product Fact: HEST Dually Custom S

  • Dually Custom S: The Dually Custom S features two layers of temperature resilient memory foam in a portable, foldable form. The dual-layer foam helps regulate temperature better than a single layer, but since HEST doesn't publish an R-value, you'll need to combine it with a suitable sleeping bag or extra insulation for cold-weather trips.

    Dually Custom S

    Dually Custom S