Waterproof Clothing

Here at Mountain Warehouse we sell jackets and trousers with all levels of waterproof fabrics to ensure you find clothing which best suits your needs.

The industry standard for measuring the quality of a waterproof material is to test the level at which water permeates the fabric. This rating is given in mm (2,000mm for example) and the higher the number, the better it is at protecting you from wet weather.

When thinking about what waterproof clothing to buy, you first of all need to consider what you will be using the clothing for.

Breathable Outerwear

If youre planning to use your clothing for activities such as hiking and cycling, then you should consider clothing which is both waterproof and breathable. At Mountain Warehouse we use IsoDry fabric technology to ensure our garments are waterproof and breathable. This type of fabric stops rain and wind from getting in, whilst allowing your perspiration to evaporate to keep you dry. You should also look for clothing with taped seams, which ensures that the stitching on the fabric is also fully waterproof.

For venturing further up into the mountains, on more adventurous hikes or climbs, our Mountainlife Extreme range has been tested to ensure that in the toughest of weather conditions it will keep you warm and dry. With our IsoDry 5000 to 10,000 ratings the fabrics have been designed to be waterproof and highly breathable for anything that you throw at them.

Just-In-Case Jackets

For a jacket that is great for walking the dog or in day to day conditions, a purely waterproof jacket will be more than adequate for shorter periods of rain. If you are looking for a just-in-case option when out and about, or on holiday where space is at a premium, a packaway jacket and trousers will suit your needs perfectly. Taking up little space in a bag or pocket, they are great for short rain-showers, but offer no breathability.


Waterproof Definitions Explained:

Shower Proof/Water-resistant

The fabric has been treated with a water-repellent finish to allow rain water to roll off the surface to offer protection from light rain showers.

Waterproof Fabric

The fabric has a waterproof membrane or coating that prevents water droplets penetrating through the fabric. Please note that without taped seams water may be able to seep into any stitched areas.

Taped seams

The seams of the garment are sealed to stop rain seeping through the stitched areas of the fabric. Taped or welded seams are used to make the garment fully waterproof.


The fabric has a waterproof membrane or coating that prevents water penetrating through the fabric. A waterproof garment will have taped seams and therefore will be fully waterproof. It is the combination of taped seams and waterproof fabric that make a garment fully waterproof.


The fabric prevents wind passing through it, therefore eliminating wind-chill keeping you warmer. Fabric that is waterproof will also be windproof. 


The fabric is permeable to tiny water vapour molecules allowing perspiration to escape whilst still remaining a barrier to water droplets. This means the fabric remains waterproof and also breaths, keeping you cooler and dryer.

Hydrostatic Head

The waterproof level of the Mountain Warehouse jackets is tested by pouring water through a tall cylinder over the fabric, the level at which the water begins to penetrate the fabric determines the measurement. The hydrostatic head measurements range from 1500mm to 10,000mm, the higher the hydrostatic head the longer the fabric will remain waterproof. The minimum level that will be considered waterproof is 1500, this means that fabric will resist 1500mm of water being pushed onto it.


The fabric used by Mountain Warehouse is called ISODRY, this is a waterproof and breathable membrane constructed of one way valves trapped between two to three layers of fabric, this allows water to pass through one side but not the other eg: perspiration will be drawn out, but rain will not seep in. The greater the number of valves the faster moisture will be drawn out. 
The measurements used on our waterproof garments show the waterproof versus breathability for example; 2000/2000 – this means that the garments has a hydrostatic head measurement of 2000 and will remain breathable to this level. 
Please be aware that extreme conditions may push a garment past its limits, before purchasing a waterproof garment it is important to understand the waterproof capabilities and be aware of the conditions you are likely to encounter.