At One Place

What is a Wetsuit made of?

What is a Wetsuit made of?
Closed-cell neoprene foam full of nitrogen bubbles, faced with stretch jersey — the gas insulates, not the water.

The common explanation — that a wetsuit works by trapping a thin layer of water that your body heats — is mostly wrong. The insulation is the nitrogen in the closed cells of the foam; trapped water is a liability that carries heat away, which is why suits are fitted tightly and why flushing at cuffs and neck is what makes you cold. The consequence at depth is that the foam compresses, the bubbles shrink and both insulation and buoyancy drop sharply, so a 5 mm suit at 20 metres is not a 5 mm suit any more. A drysuit avoids the whole problem by keeping water out entirely and insulating with undergarments.

Component by component

Every material is a choice, and the third column is the constraint that drove it.
Part Material Why that material
foam core closed-cell polychloroprene (neoprene) foam Millions of sealed nitrogen bubbles make it a poor conductor of heat, and being sealed they do not fill with water.
facing nylon or polyester jersey laminated to one or both faces Raw neoprene tears easily and grips skin; the jersey makes it durable and possible to get into.
seams glued and blind-stitched, or taped and liquid-sealed Flushing at the seams is the main route for cold water entry, so seam construction matters more than thickness in cold water.
alternative rubbers limestone-derived neoprene, or natural rubber from guayule or hevea Conventional neoprene comes from petroleum; both alternatives address that, and the natural rubber versions are also more elastic.

Other clothing and kit objects

Common questions

What is a Wetsuit made of?
Closed-cell neoprene foam full of nitrogen bubbles, faced with stretch jersey — the gas insulates, not the water.
What is the foam core of a Wetsuit made of?
Closed-cell polychloroprene (neoprene) foam. Millions of sealed nitrogen bubbles make it a poor conductor of heat, and being sealed they do not fill with water.
What is the facing of a Wetsuit made of?
Nylon or polyester jersey laminated to one or both faces. Raw neoprene tears easily and grips skin; the jersey makes it durable and possible to get into.

Related pages

Sources

  1. Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked