does anyone have experience with pertex quantum fabrics in rain wear?

i'm looking at Rab's bivies, one made of pertex and one of event. the weight difference is 10 oz, the price difference is $120. my uses for the bivy will be:

1. when hiking solo as a stand alone shelter
2. adding warmth and extra protection for winter/cold with my current 3-season shelter (tarptent)
3. using it as an emergency shelter for alpine climbing

i understand event is waterproof, and pertex is described as "highly water repellent". so what do you guys think?

Rab Superlight - event - 17 oz - $190
Rab Ultra - pertex quantum endurance - 7 oz - $80

I think you answered your own question:

"I understand eVENT is waterproof, and Pertex is described as "highly water repellent". So what do you guys think?"

That's the critical difference - one is waterproof and one is merely resistant...and which you choose depends on the environment you're in. Most folks who use tarps often use a Pertex (or similar) bivy as it deals well with condensation, dew, etc. If you're using an exposed bivy, then something like eVENT is a better option. Since you mentioned using it as a shelter by itself, then eVENT seems like the best choice.

Pertex is a family of fabrics, some of which are waterproof. Pertex Shield, as used in the Rab Survival Zone bivi bag, is waterproof. Pertex Quantum Endurance is just about waterproof - it has a hydrostatic head of >1,000mm - but this probably won't last.

Edited by Christownsend on 08/24/2009 17:05:35 MDT.

Pertex Quantum is great for what it was designed for - Down Proof - not water proof. It will wet out and get you wet in the first rain that lasts more than a few minutes.

E-vent and Pertex Shield are designed to be water proof.

Go with the E-vent and you will be happy.

Oops! I missed the word Endurance out of my first post (I've added it now). Pertex Quantum is not very water resistant, Pertex Quantum Endurance, which is used for the Ultra, is the one with the 1,000mm hydrostatic head.

Hi Chris,

Their is no such thing as Pertex Quantum Endurance. Pertex has a line of what they call Endurance. My Pertex swatch book lists 8 different versions of Pertex Endurance.

You are correct that it has a 1000 mm water column, listed as "highly water resistant". Pertex says, "We don't classify Pertex Endurance as waterproof. The outer surface of the fabric is treated with a water repellent finish to prevent water being absorbed into the nylon fabric."

Hi Bill,
I've had a Rab Quantum Endurance 250 sleeping bag for years. From what i believe, it was the Quantum fabric with the Endurance coating. The specs seemed to change over the last few years, although Quantum Endurance is still listed on the Rab website.

Pertex used on Rab products HERE

Edited by MikefaeDundee on 08/24/2009 23:05:13 MDT.

Bill, the Pertex website is confusing. But as Mike points out Rab use Pertex Quantum Endurance so it certainly exists. As well as the DWR it has a thin membrane on the inside to provide the waterproofing.