An Ode to DWR

Being a true KitPest isn’t just as matter of buying loads of gear.  It’s about knowing what gear is worth buying, and most of all how to get the best out of it.

Gear maintenance is vital in making sure that expensive bit of kit you’ve purchased keeps performing as advertised.  If you don’t maintain your kit, that £400 super-sexy jacket will shit the bed just as rapidly as a £20 one.

For this article I’m going to concentrate on DWR and how that relates to maintaining your kit.

DWR stands for Durable Water Repellence. DWR is a chemical or otherwise artificial coating that is applied to a substrate to repel water.  It is found in all sorts of places.  From clothing to helicopter rotor blades.

DWR is not a new thing.  Adding a coating to fabrics to increase their water repellence has been done for centuries.  Cloth has been waxed or oiled.  Boots have been waxed or polished.  All of which are means of DWR.

Waxed Jacket

For the purposes of this discussion I will focus on clothing and equipment.

In clothing the most common place you will come across DWR is on your Gore-Tex jacket.   It is what makes water bead up on the outer surface, and run off.  In a water resistant jacket that uses a Gore-Tex, or other selectively permeable membrane, the DWR coating on the outer layer of the fabric is a vital part of the jacket’s ability to keep you dry.  When the outer layer can no longer shed water from its surface, you experience wet out.  At this point the super sexy membrane in your jacket that takes moisture away from your body can’t do that any more.  You are now wearing a cold, wet bin bag.  Possibly a very expensive one.

A “wetted-out” jacket.

All is not lost however!  All you need to do is renew this coating.  There are tons of products available which will do this for you.  My personal preference is Nikwax TX Direct.  This comes either as a spray or as a liquid you can add to your washing machine. Hey presto your expensive bin liner is now back to being the super sexy, high performance jacket you bought originally.

Wet kit is heavy kit.  Millilitres mean grams.  Not to mention the nause of water seeping into backpack and making the contents wet.

As a hiker, backpacker or backcountry hunter, it is well worth treating your load bearing gear too.  When you bring your pack into your tent at the end of the day, you don’t want it adding to the damp in the air or increasing the condensation as it dries out.

Shall we go a little further again?

It’s well worth treating other equipment too.  Personally I keep my gaiters treated, as well as any outer layer that would be worn when it’s not raining but still damp. Not to mention my sleeping system.  Keeping the outer shell of my sleeping bag treated means that condensation drips don’t soak into the insulation and degrade its performance.  This worked so well on my Carinthia Defence 4 sleeping bag on a recent trip, that I came back from a day on the hills to find a small puddle on the surface of the bag which hadn’t penetrated to the insulation!

One more step…

Shelters.  Tarps/bashas and tents.  All of these have weak points along their seams.  Seam sealing is a must.  However DWR applies here just as much as it does on any other equipment. 

Tents are usually advertised as having a water repellence based on a  measurement called hydrostatic head.  This is usually presented in millimetres.  What it means is if you were to get a tube of water and stand it on the tent fabric, the given height of millimetres of water in that tube is the point at which it will penetrate the fabric, and seriously ruin your day. 

This will be degraded if the outer surface cannot readily shed water.  Your 5000mm hydrostatic head is now significantly less! 

Your Basha or tarp is no different.

Further you need to think about your tent inner.  Tent inners are usually made of an absorbent (cheaper…) fabric.  The inner serves to isolate you from the condensation that will form on the inside of the flysheet, as well as provide an airspace for insulation.  This condensation will drip onto the inner.  Wouldn’t it be better if this beaded up and ran off rather than soaking into the fabric and making your living space damp?

Your basha is no different.  Better to be able to shake off most water before you put it away and make your kit soaked through…

Keeping on top of your DWR on your gear is well worth the effort, and also will enhance your comfort when you are out in the elements.  You’ve spent the money, so now make the most out of your gear!

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