New Gore Bivvy Bag Helps You Breathe More Easily

Gore has announced a new bivvy bag fabric with greater gas permeability which, they say, means the bag can be used completely sealed in extreme weather conditions.

The fabric uses a new, improved Gore-Tex membrane which, says Gore, not only allows more gas to flow both in and out of the bag, even when sealed, but also improves insulation. Gas permeability is crucial with bivvy bags, which use a different grade of Gore-Tex to shell clothing since without gas permeability, it's erm, impossible or difficult to breathe.

In tests Gore found that the air inside a bivvy bag made from the new fabric remained 'up to 19 degrees warmer when the outside air temperature was minus 20 C'. Water and wind proofing remains unimpaired, but volunteers were 'more comfortable' even in 'exceptionally heavy rainfall'.

It's an interesting development for the UK where generally wet, damp conditions mean that most bivvy bags are simply impractical because they don't breathe sufficiently well to prevent internal condensation. The new fabric, says Gore's John McDonald, 'Remains comfortable in even the most extreme conditions'.

New generation Gore bivvy bags will be in the shops early next year with models available from Terra Nova, Mountain Range and Equip.

Gore-Tex web site