Closed-cell foam pad

Closed-cell foam pads are a longstanding choice for backcountry sleeping systems. The foam consists of tiny sealed cells that trap air and provide insulation, while the structure resists water absorption. These pads are typically folded or rolled on the outside of a pack and can withstand significant rough handling.

One of the main advantages of closed-cell foam pads is their durability. Unlike air pads, they cannot leak and will continue to function even if nicked or compressed. They also provide a dependable layer of insulation on snow or cold ground, though the level of comfort and warmth depends on the specific product.

Because they are relatively bulky, foam pads are often carried externally on packs. Some designs are scored or accordion-folded for easier packing and multi-use configurations. Hikers may use sections of foam pads as sit pads during breaks or as reinforcement in frameless pack designs.

In particularly cold conditions, some hikers combine a closed-cell foam pad with an air or self-inflating pad to increase overall R-value and redundancy. This layered approach can provide both comfort and a backup in case one component fails.

For long-distance hikers, closed-cell foam pads represent a low-maintenance, reliable option that trades some comfort and packability for simplicity and resilience.