Waterproof Jackets Compared: Breathability, Weight and Price for UK Hiking

You can stay perfectly dry in a jacket that costs less than a pair of walking boots, and finish a walk soaked in one that cost three times as much. The label rarely decides it. What decides it is whether the jacket suits the day you are actually having: the wind-driven rain on an exposed Snowdonia ridge, the soft drizzle of a Chilterns morning, the sweat you generate hauling a loaded pack up a Lake District pass. This comparison looks at the three things that matter most — breathability, weight and price — and how they trade against each other.

The numbers worth checking first

Most waterproofs are sold on two figures. The first is hydrostatic head, which describes how much water pressure a fabric resists before it leaks, measured in millimetres. The second is breathability, usually given as a moisture vapour transmission rate in grams per square metre over 24 hours, or as an RET value where a lower number is better.

For UK hill walking, a hydrostatic head around 10,000mm will cope with most rain you meet on a day walk. Head towards 20,000mm and above if you are regularly out on exposed ground in sustained, wind-driven rain — the sort of forecast that uses the word "persistent" and means it.

Breathability is where budgets bite hardest. A cheap jacket with a 10,000mm shell keeps rain out perfectly well. It simply will not let your sweat escape, so on a long climb you finish as damp inside as you would have been outside. If you run hot, or walk hard, look for figures around 15,000 to 20,000g/m²/24h, or an RET of 6 or lower.

Breathability: the part most jackets oversell

Construction matters as much as the rating. Two-layer jackets bond the membrane to a loose lining, which is comfortable but bulky and slow to dry. Two-and-a-half-layer jackets add a printed or sprayed protective layer instead, saving weight at the cost of a slightly clammy feel against the skin. Three-layer jackets laminate the membrane between an outer face fabric and an inner scrim, which is the most durable and usually the most effective — and the most expensive.

Two things quietly undermine breathability, whatever the tag claims. First, a tired durable water repellent finish: once the outer fabric wets out, the membrane cannot pass vapour efficiently and you feel damp from your own sweat. Second, a lack of ventilation. Pit zips, mesh-lined pockets and a two-way front zip move more moisture in ten minutes of climbing than a fancy membrane manages over an hour.

Layering does the rest. A breathable shell over a cotton T-shirt is a mistake; over a light synthetic or merino base layer, it works.

Weight: what you gain, what you give up

A lightweight shell — roughly 300g or less — is a genuine pleasure to carry, and you are far more likely to pack it "just in case", which is half the battle in British weather. The catch is durability. Very light fabrics use thinner face materials, and they abrade faster against pack straps, stone walls and the rough gritstone edges of a stile. If your walking involves a lot of scrambling or a heavy pack, a slightly heavier jacket often lasts years longer and works out cheaper per outing.

What your money buys at each level

Prices vary widely between sales, brands and seasons, but the pattern is fairly consistent:

• Entry level. Coated fabrics or simple two-and-a-half-layer construction, basic hood, few pockets, modest breathability. Perfect for lowland walks, dog walks, town errands and the school run. Fine in a shower, tiring on a long climb.
• Mid range. Better breathability, pit zips, a hood that adjusts properly, taped seams throughout and a cut designed to move with you. For most UK hill walkers this is the sensible place to land.
• Premium. Three-layer construction, high figures on both the waterproof and breathability scales, lower weight for the same protection, and a hood and shoulder design refined over years. You are paying for fit, longevity and comfort as much as for the numbers.

Features that earn their place

1. A hood with three points of adjustment and a stiffened peak that moves with your head, not against it.
2. Pit zips, ideally with two-way sliders so you can vent without exposing your torso.
3. Chest pockets set high enough to clear a hipbelt or climbing harness.
4. A front zip with a decent storm flap or a properly water-resistant zip, not just a flap of fabric.
5. Velcro cuffs and a hem drawcord you can tighten with cold, wet hands.
6. A cut that fits over your midlayer without billowing like a sail in a headwind.

Matching the shell to the walk

Lowland and valley walking

An entry-level jacket is genuinely enough here. Rain is usually lighter, you are rarely far from shelter, and breathability matters less than packability. Spend the saved money on boots.

Upland day walks

This is where the mid range proves itself. You want a hood that stays put in a gust, pit zips for the climb, and enough breathability that you are not soaked from the inside by the time you reach the summit cairn.

Multi-day routes and winter

Prioritise durability, a cut that works over several layers, and a hood that fits over a hat without restricting vision. Weight matters less when the jacket is on your back rather than in it.

Choosing with confidence

Take your midlayer to the shop, or order two sizes if you are buying online, and check the reach in the arms before you commit. Then read the care label — none of this technology survives regular washing in biological detergent. Wash your jacket with a technical cleaner, tumble it on low or iron it through a cloth to reactivate the water repellent finish, and it will bead and breathe again. Look after it, and even a modest jacket will outlast a neglected premium one.

Photo: Yaroslav Shuraev / Pexels