Waterproof Jackets - Buying Guide - GO Outdoors

The right waterproof jacket will keep you protected from the rain, whilst allowing sweat to escape so you stay comfortable. Choosing the right jacket for the conditions and the activity is easy with this guide that explains precisley what you need.

Alternatively, check out our full range of Waterproof Jackets as well as Womens Waterproof Jackets online or in store.

What is waterproof?

Simply put, waterproofing is a garment’s ability to resist water and moisture.

The ability to repel water is tested in lab conditions by a fabric's ability to keep out a certain amount of water, and is measured by standards by (in the UK) known as PSI, or pounds per square inch, or the Hydrostatic Head. Head is measured in mm and pressure is measured in pounds per square inch.

The hydrostatic head, sometimes denoted as HH, is a test in which a fabric is held taut underneath a sealed tube of water 1 inch in diameter. Over 24 hours it is observed to see how many millimeters of water the fabric can withstand before it leaks through. When the fabric begins to seep water, the mm is noted. This is known as the jackets ‘hydrostatic head’ which literally means: Hydro –Water, Static – Not moving, Head – Height.

The PSI relates to the amount of water pressure that a garment can withstand both from the pressure within the garment (the wearer) and the external conditions (the weather).

To be 100% waterproof, the British Standard of 3 PSI has to be met, which means the jackets can withstand 1500mm of water pressure. Pressue is not as simple as the pressure of a rain storm, simoply moving in the jacket will exert pressure on the fabric. Typical activities like kneeling and walking will generate 8000mm of pressure, so if a jacket is selling itself on a PSI - go higher!

Most jackets typically exceed the minimum level anyway, reachinga round 40 PSI. Generally, the higher the PSI, the more effective the waterproofing will be. However the higher the PSI level and the more effective the waterproof is, the more expensive the jacket will be, so choosing should be a choice based on what you can afford, where you will use your jacket, and what other features it has in it's favour.

The importance of breathability

As well as getting a jacket that's waterproof, it needs to be breathable. When you're moving with speed, or walking up hills, you will raise your heart rate and cause sweat to be released. For this reason, you need to consider the breathability rating of your waterproof jacket.

This is measured in MVT, or moisture vapour transfer, literally, how much mositure can be transferred into a garment over a 24 hour period. In tests this is displayed as 10,000 gr/24hrs/m², but the breathability is often displayed simply as 10,000gr. 10,000gr to 20,000gr of breathability is generally effective enough to cope with fast paced outdoor activities like hiking, climbing and skiing, although how the jacket is constructed will have a greater effect than the scientific study of breathability. Your own body chemistry will affect how you sweat too, and on top of this, the other features such as zips, vents and fabrics used may all affect the breathability as well.

Our advice would be to take the breathability ratings with a pinch of salt, and think about how the jacket will perform in the outdoors, asking questions like:

• Can you roll the sleeves up? 
• Are there pit zips? 
• Does it have a bonded inner liner?

Although there are a huge range of waterproof jackets with different names, different fabrics and different coatings, they fall essentially into two different types: membrane, or coated.

The Berghaus Sancity Jacket® above shows a multi functional waterproof made with GORE-TEX® Pro Shell for waterproof and breathable performance.

Membrane waterproof jackets

Membrane coated waterproofs are jackets with a membrane construction, the big names being GORE-TEX® and eVent®. (GORE-TEX® also uses a PU layer). A membrane jacket will out-perform a coated waterproof by about 25-30% greater efficiency on moisture movement and control.

• GORE-TEX® is the most established brand of microporous membrane. It consists of a wafer-thin expanded PTFE - pronounced 'Poly-tetra-fluoro-ethylene', also known as Teflon, a fabric where each pore is 20,000 times smaller than a water droplet! The beauty of the PTFE is that the fabric holes are 700 times larger than a body moisture molecule. The fabric therefore has excellent levels of waterproofing and breathability. e-Vent® fabrics are created from a waterproof membrane which is also breathable.
•  Similar to GORE, e-Vent uses millions of pores in its construction which allow the fabric to release moisture and to breathe. Without a PU layer included, breathability is increased as moisture is moved in one process, known by e-Vent as Direct Venting.
• Paramo® is referred to as 'drop-liner', meaning that the waterproof element is actually inside the lining. There are three constituent components: two layers of fabric and a waterproofing agent. The fabric is impregnated with Nikwax® TX Direct treatment that leaves a water-repellent finish on each individual fibre so that the outer layer, as well as being fully windproof, will deflect at least 90% of water that hits it. Paramo® is extremely breathable: no matter how hard the wearer works, or how much they sweat, body moisture will be moved away.

Breathable membranes consist of an extremely thin film containing microscopic pores that are large enough for body moisture to pass through, but small enough to keep water droplets out. Most microporous membranes are laminated to a face fabric and are available in two- and three-layer versions.

In the case of GORE-TEX®, a plastic based PTFE (Polytetrafluoroethylene) layer is laminated to the outer fabric, and then the garment is cut to shape. Seams are then sealed for complete protection The seams are then sealed to prevent moisture entering the garment in any way. Hydrophilic coatings rely on the behavior of water molecules so heat generated by the body inside the garment drives body moisture down the polymer chains in the coating to the external face.

This is also known as moisture management. Most membranes rely on a pore based construction, so as well as being waterproof, they can also vent out hot air and sweat.

A 3 in 1 Jacket like the Sprayway Alver 3 in 1 above is a great way of getting waterproofing and warmth. 3 in 1 is also described as interactive, or 'IA'.

Coated waterproof jackets

The other alternative is a waterproof that's been coated with a Durable Water Repellency (DWR) or a similar layer, with no breathable membrane. These are typically your cheaper waterproofs. DWR is Durable Water Repellency, another way of coating the fabric after a laminate or membrane has been applied to form a protective wall from water droplets on the outer layer.

A chemical treatment, DWR is not waterproof, but does reduce condensation forming; aiding breathability so less moisture reaches your skin. DWR needs to be reapplied, and can be retreated to improve it’s performance. Due to DWR being applied to the face of the fabric, it is easily affected by dirt and oils, which soon coat the DWR layer, hindering the performance. DWR can also be removed by regular cleaners, so DWR should always be treated with a specific product which can refresh it. As well as DWR, many companies have their own water repellent fabrics applied to the face of the garment such as:

•  Lowe-Alpine Triple Point
• Triple Point Ceramic
• Mountain Equipment Drilite and many more.

 Breathability is severely hindered in these types of waterproofs. Arguably more important than being windproof or waterproof, breathable capabilities in a garment mean it allows body moisture and vapors to be released, so you can use it for active wear without overheating or feeling discomfort.

Wicking is a garment’s ability to progress moisture away from the skin via the fibres.

 A wicking fabric is designed to move moisture away so it dries quickly, rather than absorbing the wetness. (Breathable garments do not ‘stop’ you sweating or producing moisture, which is a natural response, but allow drying to happen quickly.) Breathability is particularly important in active wear. The more of your own body heat you will be using and producing, for example on an uphill trek, the more breathability you will need.

The balance with breathability is between letting enough moisture escape, whilst keeping moisture out, whilst at the same time preventing condensation. The benefit of membrane waterproofs is seen here again. As water droplets are too large to enter the membrane garment, they do allow moisture vapors to escape. Coated waterproofs hinder this process. This can be seen in membranes, too, when the factory-applied DWR coating breaks down, the breathability technology in a garment is hindered, and it needs to be reproofed.

Reproofing a waterproof jacket

Reproofing with the right detergent like Nikwax® or Grangers® can extend the life of your waterproof jacket.

We recommend two main methods of proofing and cleaning, either by Nikwax- the inventor of Paramo®, or with Grangers. Proofers are made from water-repellent elastic polymers, or elastomers . They coat the fibres with a storing yet breathable layer. Both brands offer a selection of specific fabric cleaners and proofers which work together to clean and proof your jacket. You can clean you waterproof jacket with either a Nikwax or Grangers spray on or wash in cleaner that takes away detergent residue, oil and dirt that may have been hindering you waterproof.

You can then use a proofer as a second stage, which is either spray or sponge on. This can be used to enhance lacklustre breathability or waterproofing by enhancing the factory water repellent once more.

• Before you apply a proofer ensure that the garment is clean, and that all zips and velcro straps are closed.
•  If the waterproofing solution is water based apply it to your jacket when it is damp, similarly if it is a dry solution, apply it to a dry jacket. 
• Coat the jacket and then dab any excess moisture off with a clean cloth.
• Grangers recommend tumble drying (usually with a professional dryer, not a home dryer to avoid damage from commercial features) and Nikwax recommends air drying. Air drying is usually the safest choice, but the heat of a tumble dryer is there to help bond the elastic polymers of the proofer.

 We recommend that you read the care label of your jacket before you follow the instructions of the proofer in the case of tumble drying, as all fabrics vary. You can proof your jacket using the full process, and then just get away with washing your jacket with a technical wash for the next 4 washes, although you should reproof your gear once a year.
 

The alternative- windproof jackets

One question we would ask any fairweather outdoor adventurer is, are you sure you need a waterproof jacket? This might sound strange, and we aren’t trying to discourage you from getting one, but as many enthusiasts are keen to point out, if you are a ‘fair weather’ walker, you are unlikely to ever be out in the pouring rain unless you get hit by very unpredictable weather. What will bother you is the wind, particularly when you are at height, or running or climbing against it it. Hill walking or climbing can increase your exposure to winds as oppose to walking in lower areas, such as valleys and dips. Without windproofing protection, cold vapors can reach you, causing chills and discomfort. Windproof items typically also have some water resistance, but tend to be more breathable than waterproof alternatives.

If wet weather would prevent you from going out anyway, you could look at a lower weight, more breathable windproof jacket as an alternative.Many runners and cyclist find that these take off the cold edge of the wind, but allow heat to escape more effienctly than a waterproof.

If you’ve chosen your fabric and you are sure you want a waterproof then don’t forget to get a jacket that’s fit for purpose.

Lowland Walking / Rambling - Lightweight Waterproof Jacket

• These are ideal for the casual walker who doesn’t expect to need to wear it all day, and those who are packing light. This is where you can choose from a coated waterproof to keep costs down.
• They can be used for general hiking, summer day trips, street walking and times where there may be a chance of rain.
• Many runners may use these lightweight waterproof jackets as they are mandatory for many ountain marathon and fell races.

Hill Walking / Trekking – Midweight Waterproof Jackets

• These are functional jackets designed to give the highest level of weather protection for the dedicated hill walker.
• They usually have tougher fabrics and more technical design to give you maximum performance on the mountains. This is where you will need a membrane waterproof, like a GORE-TEX® jacket, eVent® jacket or Dewpoint® jacket.
• These are functional jackets designed to give the highest level of weather protection for the dedicated hill walker.
• These tend to have tougher fabrics and more technical design to give you maximum performance on the mountains.

Mountaineering / Snowsports - Specific Ski Jacket

• These are highly specialised jackets designed for rock climbing, ice climbing, summer and winter mountaineering and snowsports.
• They need to be suitable for steep slopes and wet winter weather conditions of the northern parts of Scotland.

Features to look for

Hood

As you lose over 30% of your body heat through your head it is important to keep it protected and warm. Your hood can be fixed or detachable and as you probably need to see where you are going when you GO Outdoors, you have to make sure that when it is when done up, it doesn’t impair your vision in any way. You may also want to fit a helmet/hat under your hood, so keep an eye out for compatibility and a visor if you want to see more.

Zips

• Zips are the most important closure method in all jackets. They allow you to get your jacket on quickly when the conditions worsen, or take it off when the sun appears. Some jackets have 'Zip-in Compatibility' for complete comfort and protection. 
• Zip-in-Compatibility means you can zip a specific fleece mid-layer into the jacket using inner zips giving you a complete layering system to protect you from cold and wet conditions.
• Zips and vents allow your body to cool down without taking off a layer whilst pit zips offer fresh air for those underarms that can get sweaty if carrying a rucksack for a long period of time. Core vents, such as front zips and ventilation flaps, allow your body heat to dissipate therefore increasing ventilation and keeping you cool.

Pockets

• Most pockets on waterproof jackets should have storm flaps to protect the opening of the pocket from water. In newly designed jackets most of the pockets (including chest pockets) may have a mesh lining to increase ventilation, if open, through the jacket. 
• Chest pockets can range in size and most offer space for an OS map or at least a mobile phone or snack to eat while walking. Mountaineering jackets usually only have chest pockets due to the harness reducing access to waist pockets.

Seams

For a waterproof jacket to be classified as a waterproof, seams must be sealed. The only exception to this is the Paramo Analogy which works via a 'Pump Liner', which actively pushes liquid moisture away from the body keeping you dry.

Drawcords

These should be elasticated for increased flexibility and movement to allow you to climb, run, walk, or ski without being impaired by the jacket. The toggles for this will generally be found at the hem, waist and at the collar to allow shaping of the hood.

The North Ridge Kalias Jacket above demonstrates good functional zips, a multitude of pockets drawstring closures as well as a large 'grown on' deep hood for full protection.