Closed-Cell Foam

Closed-cell foam describes a foam structure where each bubble of air is completely sealed, creating a dense, non-porous material. This foam architecture is common in PVC, TPE, and many other yoga mat materials, and it has significant practical implications for hygiene and performance.

How Closed-Cell Differs from Open-Cell

In closed-cell foam, each gas bubble is encapsulated in its own polymer wall. In open-cell foam, the bubbles connect and form an interconnected network (like a sponge). This structural difference creates dramatically different material behavior.

Closed-cell foam does not absorb water or sweat, is easy to wipe clean, maintains structure over time, but is less breathable and heavier per unit of cushioning.

Open-cell foam absorbs moisture readily, is more breathable and softer, requires thorough drying to prevent mold, and compresses more easily over time.

Why Closed-Cell Matters for Yoga

Most mainstream yoga mat materials (PVC, TPE, EVA) use closed-cell foam construction:

• Hygiene: Sweat stays on the surface where it can be wiped away, rather than soaking in
• Durability: The sealed structure resists compression and maintains cushioning longer
• Grip consistency: Surface properties stay consistent as the mat ages

The downside of closed-cell construction is that the surface becomes slippery when wet. Sweat cannot soak in, so it pools on the surface.