Waterproof Breathable Fabrics

Waterproofing and Breathability are NOT just a yes or no feature in a Shell.  There is a wide spectrum of both Waterproofing and Breathability and knowing the difference can mean the difference between you being very wet or nice and dry on an outing. 

About Waterproofing and Breathability 

Prior to 1976, you had 3 choices for waterproofing: vinyl; waxed or treated cotton; or just getting wet and staying warm with wool.  Part of being in the rain was getting wet, either by not having a rain shell or from the accumulation of perspiration under your shell.

Gore-Tex was introduced in 1976 and changed how we enjoyed the outdoors with the introduction of a waterproof AND breathable fabric.  The new choice was simple - stay dry with Gore-Tex or get sweaty with a nonbreathable shell.

Fast forward to 2008/2011 and eVent and Polartec NeoShell enter the market as alternatives to Gore-Tex.  eVent promoted increased breathability by not using a polyurethane protective coating and NeoShell was made with a more affordable polyurethane membrane.  Shortly after that, many of the big outdoor companies started manufacturing their own proprietary waterproof/breathable fabrics.   There are now now dozens of different materials to choose from and it's no longer a choice between Waterproof/Breathable and Waterproof/NonBreathable.  There are now full spectrums of waterproofness and breathability to choose from.  Unfortunately, it isn't always clear when shopping for clothing and gear how waterproof or breathable things really are. 

Summary 

• Fabrics vary greatly in their waterproofness and breathability 

• High performance Waterproof/Breathable Fabrics are desirable for Pacific Northwest Winters where it gets really really wet

• Without a shell with a rating of 20K/20K, expect to get wet from snow, rain and perspiration

• Wetness in the winter leads to discomfort, misery and places you at risk of hypothermia

• Gore-Tex is very waterproof and reasonably breathable and is the preferred fabric for your shell layer

• Gore-Tex Pro is more breathable and even better

• Other fabrics will protect you from moisture to varying degrees

  • Most other fabrics are not as waterproof or as breathable and Gore-Tex

  • A few are as good or better than Gore-Tex

• All fabrics need to be maintained, otherwise they lose breathability as well as fail to shed water 

Waterproofing Ratings

• There are multiple ways of measuring how waterproof a fabric is

• The most common method is the Water Column Test

  • Waterproofing is measured by placing a 1” x 1” square tube over the test fabric and measuring how high a column of water in mm you can suspend over the test fabric before it begins to leak

  • <5000mm: Light Rain/Snow and NO Pressure

    • Water Resistant 

    • Protects you from light rain or snow for a short period of time

    • REI Co-op considers 3 psi (2,109mm) or higher to be "rainproof"

  • 5,000-10,000mm: Moderate Rain/Snow and Light Pressure

    • 5,000mm is good for intermittent moisture

    • 10,000mm good for wet days where you can take breaks and sleep indoors

    • Many argue that 10K Waterproofing is sufficient for all needs

  • 15,000-20,000mm: Heavy Rain/Snow and Moderate Pressure

    • The Pacific Northwest has extremely wet snow

      • The Pacific Northwest has a maritime, temperature driving snowpack resulting in a very wet and dense snowpack

      • "Cascade Concrete" is very wet snowfall that is just cold enough to fall as snow and warm enough to easily turn liquid

      • Unlike other snowy alpine environments that are dry, temperatures here are often hovering around or above freezing

      • Kneeling/sitting/lying/falling on PNW snow and exposure to heavy winds, snow and rain require more protection than in other environments

    • 20K Waterproofing is preferred for the Pacific Northwest Winters

  • 20,000+mm: Heavy Rain/Snow and High Pressure  

    • Pressure becomes more important when kneeling or sitting on snowpack

    • 30K or vapor barrier waterproofing is often used for maritime use

    • Motorcyclist who ride at high speeds in cold rainy environments are going need extra protection 

    • Classic and Pro Gore-Tex is rated at 28,000mm

• Seams MUST be seam taped or welded, otherwise water will just leak through seams

Breathability Ratings

• • There are several methods for measuring breathability

    • The different test methods don't always yield the same results and it is difficult to compare ratings

    • There are 2 main systems of Breathability Rating - MVTR and RET

  • MVTR (Moisture Vapor Transmission Rate)

    • Ratings estimate the amount of moisture in grams that can pass through a square meter of fabric in a 24-hour period

    • 5,000-10,000g/m²

      • Satisfactory or breathable

      • Urban use or camping in rain

      • May be OK of ski use

    • 10,000-15,000g/m²

      • Good or very breathable

      • Good for outdoor use other than hiking or other high perspiration activities 

    • 15,000-20,000g/m² 

      • Extremely breathable

      • High perspiration use

      • Warm climate use

    • The Pacific Northwest are relatively warm so breathability is important

      • 15K Breathability is preferred for alpine skiing and camping in Pacific Northwest Winters

      • 20K Breathability is preferred for snowshoeing with a load in Pacific Northwest Winters

  • RET (Resistance to Evaporating Heat Transfer)

    • Resistance of the material surface to water vapor

    • The lower the RET, the more breathable it is

    • RET > 20 

      • Slightly to not at all breathable fabric.

    • RET < 20 

      • Breathable fabric

    • RET <12 

      • Very breathable fabric

    • RET< 9 

      • Extremely breathable fabric

  • Unfortunately, breathability ratings are often NOT available for many fabrics or pieces of clothing

Durable Water Repellent or DWR

• Most waterproof/breathable fabrics are treated with a Durable Water Repellent

• This reduces moisture absorption in the fabric leads to beading of water its surface

• Breathable/Waterproof fabrics needs special care

  • Waterproof/Breathable fabrics need to be washed every 150 hours of use or seasonally

  • Treat with DWR (Durable Water Repellent) after washing

  • Read manufacture's recommendations 

Seam Sealing

• Holes from thread and seam lines can allow water to leak through

• Seams can be Sealed, Taped or Welded 

• Taping over stitching and seams will waterproof them

• Welding allows you to bond fabric together using head and pressure - no open seam or stitching eliminates leaks there

• Critical Seams Sealed

  • Most vulnerable upper seams are sealed

  • Other seams will leak

• Fully Seam-Sealed

  • All seams are sealed or taped 

Laminate Construction

Most Waterproof/Breathable fabrics use a membrane or PU film that is placed between an outer and inner layer of fabric.  The other layer protects the membrane from the outside elements and the inside layer protects the mebrane/flim from your body.

• 3 Layer 

  • Outer Layer / Membrane / Inner Layer are bonded together

  • Better protected membrane compared to 2 and 2.5 layer garments 

  • Improved breathability over 2 and 2.5 Layer garments

  • Use:

    • Expedition gear

  • Example:

    • GORE-TEX Pro

• 2.5 Layer 

  • Outer Layer / Membrane are bonded together

  • A thin inner layer is applied or sprayed over inner side of membrane/film

  • Least bulky compared to 2 and 3-Layer

  • Usually the lightest option compared to 2 and 3-Layer

  • Use:

    • Ultralight shells

  • Example:

    • GORE-TEX Paclite

• 2-Layer 

  • Outer Layer / Membrane are bonded together

  • Loose hanging inner liner made from fabric or mesh protects the outer two layers of fabric

  • Insulation is sometimes added between the shell and liner

  • Generally warmer than 2.5 and 3-Layer

  • Bulkier than 2.5 and 3-Layer

  • Often heavier than 2.5 and 3-Layer

  • Use:

    • Insulated clothing

    • Casual wear

    • City wear

    • More affordable

  • Example:

    • GORE-TEX Performance

Gore-Tex Waterproof/Breathable Fabrics

Fabrics have different levels of waterproofing and breathability.  GORE-TEX is still the industry standard in Waterproof/Breathable Fabrics.

GORE-TEX 

• Their fabric has evolved over the years, so their current tech is different than their 1976 tech

• Uses expanded Teflon aka expanded PTFE (ePTFE)

  • Creates tiny micropores that let vapor through, but stop water drops

“Black Diamond” GORE-TEX 

• • Waterproof

    • 28,000mm rating

  • Maximum weather protection

  • Regular Gore-Tex

    • Gore-Tex 3-Layer 

      • Preferred for Winter Outings and Mountaineering

      • Single 3-layer laminate - Outer fabric, middle membrane and inner fabric 

      • More durable and not as bulky as Gore-Tex 2-layer

      • Better protected membrane compared to 2 and 2.5 layer garments 

      • Improved breathability over 2 and 2.5 Layer garments

      • Shell may be stiff

      • Found in more technical shells

      • Examples:

        • Gore-Tex (Classic)

          • 28K/17K

          • Uses thin layer of polyurethane on the underside of its ePTFE membrane to guard against clogging of pores

        • Gore-Tex Performance Shell

          • 28K/17K

        • Gore-Tex Pro 3-Layer

          • Premium 3-Layer Gore-Tex

          • 28K/25K

          • Uses Micro Grid Backer fabric, rather than a polyurethane to protect ePTFE membrane

          • Claims:

            • Larger pores and increased breathability over regular Gore-Tex

            • Higher level of water resistance in its coating

            • Doesn’t require any moisture to become breathable

          • Heavier weight fabric used for mountaineering and skiing 

        • Gore-Tex Active

          • Activewear version of 3-layer Gore-Tex

          • Fine denier outer fabric

          • C-KNIT inner layer

          • Increased breathability and reduced weight/bulk

          • Designed for "highly-aerobic" activities 

          • GORE-TEX Active 3L

            • 28K/25K

          • GORE-TEX C-Knit 3L

            • 28K/20K

    • Gore-Tex 2-Layer 

      • More Economical than 2.5 and 3-Layer Garments

      • Often warmer than 3 Layer Gore-Tex, especially if insulated

      • 2-layer laminate + suspended liner 

        • 2-layer laminate - Outer fabric, middle membrane

        • Liner separates body from membrane

          • Made from mesh, nylon or microfiber 

          • Protects Gore membrane

          • Feels more comfortable against skin

          • Insulation sometimes be added 

        • Bulkier than 3 and 2.5 Layer garments

        • Example:

          • Gore-Tex Pro 2L

            • 28K/25K

    • Gore-Tex 2.5-Layer 

      • Preferred for NON-Winter Backpacking

      • Lighter weight and better packability compared to 2 and 3 Layer Garments

      • 2-layer laminate + attached inner layer 

      • Printed- or sprayed-on “liner”

      • Examples:

        • Gore-Tex PacLite

          • Light and easy to pack

          • 28K/15K

        • Gore-Tex Paclite Plus 

          • 40-denier nylon face is more durable than regular PacLite

“White Diamond” GORE-TEX INFINIUM

• • WINDSTOPPER

    • Formerly known as GORE‑TEX INFINIUMTM WINDSTOPPER

  • Windproof

  • Weather-resistant - NOT waterproof

  • Designed for light rain/snow but mostly for wind

  • Breathes well

Other Waterproof/Breathable Fabrics

Fabrics other than Gore-Tex are used in waterproof/breathable garments.  These may have increased breathability and/or be a more economical option. 

Many top end clothing manufactures offer 2 choices:

• Pro Gore-Tex option

  • Weatherproof

    • 28K/25K Waterproofing/Breathability

  • Expensive

• Non Gore-Tex option

  • Uses proprietary fabric

  • Sufficient Waterproofing/Breathability for most uses

  • Much more affordable option

Examples of Variability of Waterproof Breathing Jackets

Charts show Waterproofing, Warmth, Breathability, Stretch and Durability. 

eVent

• Took off as an alternative to Gore-Tex around 2008

• Was used by multiple companies

  • Was used by REI, Rab, and Mountain Hardwear

  • DryQ Elite was a Mountain Hardwear product

• Waterproofness ranges from 10,000-30,000mm

• Considered more breathable than Gore-Tex

  • Gore-Tex 3-Layer is actually made up of 5 layers

    • Exterior Shell

    • Protective layer  

    • ePTFE membrane

    • Protective layer (thin polyurethane)

    • Interior liner layer

  • The polyurethane is used to protect the ePTFE membrane from clogging its pores

• eVent does not use an inner PU membrane

  • Oleophobic protective solution applied to PTFE at a microscopic level

  • Membrane is less protected from oil and grease

  • Requires more maintenance and reproofing

• eventfabrics.com 

• DVstorm

  • 20K/22K

• DValpine

  • 10K/31K

• DVlite

  • 10K/18K

Polartec 

Polartec NeoShell

• • Took off  in 2011 as cutting edge tech

  • Was used by Flylow, Marmot, and Strafe

  • It is used in Altra shoes

• Instead of ePTFE, it uses an porous, electrospun polyurethane membrane with an infused protective coating

• Soft and stretching fabric 

• There concern that the membrane degrades over time

  • • Supposedly it won't drop below 5,000mm

    • 5K isn't considered enough for the Pacific Northwest

• 10K/10K 

  • • Probably lost market shares due to other fabrics with 20K waterproofing

    • 10K is also arguably NOT sufficient for Pacific Northwest Winters

  • Following introduction of NeoShell to Market, other companies started making their own fabrics

Updated NewShell

• • Came out in 2016

  • Slightly lighter and more breathable 

Polartec Power Shield and Power Shield Pro

• Released prior to NeoShell

• Highly insulative fabric used in hardshells

• Power Shield Pro has improved water-resistance and breathability

• NOT Waterproof

  • • Waterproofness appropriate for dry mountains?

 The North Face

• Use Gore-Tex and their own waterproof/breathable fabrics

FUTURELIGHT

• Used The North Face

• VERY Breathable

• Electo/Nanospinning

  • “Nano-spun” membrane - similar to Tyvek 

  • Similar to NeoShell

  • Made from polyester instead of polyurethane

• 2019 tech

• North Faces uses proprietary form of seam tape

• thenorthface.com

• ?K/75K

DryVent 

• Formerly known as Hyvent

• Used by The North Face 

• Use their own system of measuring waterproofness and breathability 

• HyVent

  • Waterproofing: 25psi

  • Breathability 625 g/m2/24hrs

Outdoor Research

• Use Gore-Tex and their own waterproof/breathable fabrics

Ascentshell 

• Used by Outdoor Research

• Electo/Nanospinning

  • “Nano-spun” polyurethane membrane - similar to Tyvek 

  • Polyurethane-based fabric

  • Similar to NeoShell

• 15K/30K

Ventia Dry

• Used by Outdoor Research

• 20K/15K

Ventia 2.5L                                  

• • 10K/10K

Marmot

• Use Gore-Tex and their own waterproof/breathable fabrics

MemBrain

• MemBrain

  • 10K/10K

• MemBrain Strata

  • 20K/20K

PreCip

• Economy lightweight rainwear

• PreCip MP

  • 15K/12K

• PreCip Plus

  • 25K/15K

NanoPro

• NanoPro

  • 10K/11.5-17K

• NanoPro MemBrain

  • 10K/11.5-47K

Mountain Hardwear 

• Use Gore-Tex and their own waterproof/breathable fabrics

Conduit

• Used by Mountain Hardwear 

• 20K/29K

Dry.Q 

• Used by Mountain Hardwear 

• No polyurethane layer over the PTFE membrane

• Based on eVent technology

• Increased breathability 

• Dry.Q Active

  • 20K/15K

• Dry.Q Elite

  • 40K/30K

H2No

• Patagonia

• 3, 2 and 2.5 Layers

• Alternative to Gore-Tex also used by Patagonia

Pertex Shield

• UK fabric

• Used by Montane and some Euro companies

Pertex Shield+

• Considered to have great breathability 

• Very light weight

• Hydrophilic PU membrane

• PERTEX Shield+ 2.5L 

  • • 20K/20K 

Pertex Shield AP 

• Air-porous membrane

• Waterproofness and a good moisture permeability

Pertex Endurance

• • 1K/7K 

Toray

• Japanese company

Dermizax 

• Waterproof woven fabric with a non-microporous polyurethane membrane

• Stretchable 

• Per dermizax.toray - waterproof rating of 20,000mm

• dermizax.toray 

• Waterproofing/Breathability

  • • Dermizax 

      • 20K/4K

    • Dermizax 2L

      • 20K/10K

    • Dermizax 3L

      • 20K/8K

    • Dermizax DT 2.5L

      • 20K/18K

    • Dermizax EV

      • 20K/4K

    • Dermizax EV 2-Layer

      • 20K/20K

    • Dermizax EV 3-Layer

      • 20K/16K

    • Dermizax MP

      • 20K/10K

    • Dermizax MP 2-Layer 

      • 20K/18K

    • Dermizax MP 3-Layer

      • 20K/13K

Entrant

• • • Entrant DT 5000

      • 5K/8K

    • Entrant DT 10000

      • 10K/10K

    • Entrant DT 20000

      • 20K/13K

    • Entrant GII 2-Layer

      • 5K/9K

    • Entrant V 2-Layer

      • 10K/10K

    • Entrant W 2-Layer

      • 20K/12K

    • Entrant HB 2-Layer

      • 20K/20K

Xt.L

• Used by Spyder

• Xt.L 5K

• 5K/5K

• Xt.L 10K

  • 10K/10K

• Xt.L 15K

  • 15K/15K

• Xt.L 20K

  • 20K/20K

• Xt 5,000

  • 5K/5K

• Xt 10,000

  • 10K/10K

AQ

• Used by Berghaus

• AQ2

  • 10K/8K

• AQ2.5

  • 10K/10K

Omni-Tech

• Used by Columbia

• Omni-Tech (Adults)

  • 10K/10K

• Omni-Tech (Kids)

  • 5K/5K

Helly Tech 

• Used by Helly Hansen

• Helly Tech Performance

  • 14K/18K

• Helly Tech Professional

  • 20K/20K

• Helly Tech O2

  • 20K/24.5K

Karbonite 

• Used by Karbon 

• Karbonite 10,000

  • 10K/10K

• Karbonite 15,000

  • 15K/15K

• Karbonite 20,000

  • 20K/20K

ClimaPro 

• Used by Salomon

• ClimaPro 2L

  • 10K/10K/

• ClimaPro Active

  • 10K/30K

• ClimaPro Storm 3L

  • 20K/20K

DRYTech

• Used by Mammut (NOT Marmot)

• DRYTech 2-Layer Stretch

  • 10K/10K

• DRYTech Premium 2-Layer

  • 10K/10K

• DRYTech Premium 3-Layer

  • 20K/20K

Columbia OutDry

• Introduced in 2009

• Outer coating to apparel, footwear, and accessories

• Waterlogging prevention

• Membrane also offers waterproofing 

• Does not requiring DWR treatment

Sierra Designs

• Hurricane

  • 8K/2K

• Microlight

  • 0.6K/?

Waterproof Shell Considerations

• Shell should be large enough to fit over other layers of clothing

• Jacket must have a hood

• Rain pants are required in the winter

• If purchasing used Waterproof/Breathable shells, check for holes and that seam tape is intact

• Things to AVOID in the winter:

  • Softshells

    • Generally designed to be water resistant and windproof

    • OK for limited exposure to the outdoors - such as a quick jog

    • Not waterproof enough for extended exposure to rain, snow or heavy wind

    • As a mid layer, they are heavier and are less breathable than other items of comparable insulation value

  • Nonbreathable Shells

    • These trap condensation and sweat and make you feel muggy and hot when moving and then really cold later on