DWR

When you start to see some water not beading up and rolling off — then it's time to wash your garment and reapply the DWR. But "frequent" reapplication isn't required. I would say once every couple of years under normal use — or once every year under more frequent use.

Testing was done by a UK outdoor magazine. DWR often only lasted for a few hours of use! You can read the article here.

Mike:

The report above is so far off from my own exprience! But if the report is true, then I would expect A LOT OF BITCHING right here on this and other forums about the frequent, frequent need for DWR re-app. — but this is just not the case, is it?

My beloved MontBell claims its DWR treatment maintains 90% effectiveness even after 100 washes! While I would take that with a few grains of salt — I would also wonder if the tests linked above were done in lab conditions that had little to do with reality? Who knows?

I dislike being critical of other magazines, but this report by a UK outdoor magazine does not impress me at all. It's very amateur in its planning.

They seem to have missed a number of rather important factors in the basic chemistry of DWR treatments, and just done a blind shotgun test without much understanding of what they were doing.

Also, they tested a number of obviously not very good treatments while missing out on a number of well-known and better treatments.

My experience doesn't tie in with its findings either.
The magazine in question is very amatuerish in its approach to all its testing and reviews.
It is anti-lightweight in its approach, so is no favourite with UL UK backpackers.
I just posted the article to highlite that there isn't much scientific info about, on the merits of different DWR treatments.
A project for BPL maybe?

Interesting subject. My point of reference on this subject has been a post by Richard Nisley.

The durability is primarily determined by the DWR type rather than the fabric. DWRs, available retail, last about 30-50 miles of abrasion from either your pack rubbing on your upper body or brush rubbing against the front of your pants and lower arms. DWR life in an application like a bivy/quilt will primarily be determined by how clean you keep the Momentum90 and how much abrasion results from your use stuffing and un-stuffing.

The most durable type of DWR available to the DIYer is fluoropolymer based. Examples are: Deluge, Granger's, ReviveX, Scotchguard, or Tectron. The bivy can be easily renewed whenever you notice that drops of water soak in (wet out) rather than bead up. Key things to remember are: wash the bivy with non-detergent soap; double rinse it; spray or wash in the DWR; and then heat set it in the dryer for 50 minutes at medium heat.

The quilt's DWR renewal procedure is dependent on the insulation you used to make it and how durable the quilting technique you used is. At minimum, you can wash it as mentioned previously, spray on a DWR, and heat set the DWR with a hair dryer used on the surface for an equivalent time to the dryer.
http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/7947/index.html

I had like to hear more comments from other members.

Sounds like he got it from the same magazine source?

30-50 miles is one lousy weekend or long weekend trip! Makes me wonder why we aren't all buying six to a dozen bottles of DWR every time we shop — if in fact DWR needs to be re-applied that often?

> A project for BPL maybe?

A good thought.
A bad thought is the amount of time and gear and sample fabrics required to do a survey to the standards we set for ourselves. One day … :-)

Cheers

My experience is similar, to the point that I ignore most products claims regarding DWR. Aside from rainjackets, I consider most of my gear is eithe waterPROOF but not breathable, or not waterproof. I always get a chuckle out of folks who ask if their DWR windshirt can be used as a rain jacket!

Hi Joel

Fwiiw, you could try reading the articles on waterproofing at
http://www.atsko.com/technical-info.html

They are a bit more than half-way down the (long) page. Note especially that applying a DWR without first washing the gear in the RIGHT way is worthless. So read about Sports Wash as well.

Cheers

thank you for your comments guys.