How to choose the best waterproof trousers

The job of waterproof trousers is simple: keep you dry in a downpour. But not all outerwear is made equal. Just look at the results from our waterproof trousers survey, where Peter Storm gained an overall score of 62%, making it bottom of the table.

Most need to be big enough and stretchy enough to pull on over your hiking gear. But these aren't the only qualities to look for. 

Below, we explain how to choose microporous and waterproofing technology and what the perfect fit looks like. This should ensure you don't waste your money on a pair you can't use.

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Should you wear anything underneath waterproof trousers?

Typically, yes. You'll wear walking trousers beneath as they tend to be comfier and more breathable. You then take off your overtrousers when the rain stops. 

However, if you invest in walking trousers that are both waterproof and breathable, you may not need both pairs. Paramo is the perfect example. Although pricey, it scored well in both categories in our walking trousers survey.

Shop Paramo walking trousers

How to check the rating of your waterproof trousers

Check the trousers have been treated with a waterproof coating, and look for a hydrostatic head measurement of 5,000mm or more.

Modern waterproofing techniques are so effective that water doesn’t usually get through the main body of fabric. It’s more likely to seep in through the zips, seams and pockets. Features such as taped seams, storm flaps to cover the pockets and zips, and Velcro ankle tabs should reduce the chance of leaks.

Should they be ventilated?

If you’re out on a challenging walk, it won’t be long before you start to sweat, and this can lead to condensation and dampness building up inside your waterproofs. Some waterproof overtrousers include three-quarter-length zips that run up the side of the leg and can be opened to allow air to circulate.

Often, overtrousers are made using microporous fabrics, such as Gore-Tex or eVent. These fabrics contain a membrane with billions of microscopic holes too small for water to get through. Instead, the water forms beads on the outer surface, where it eventually dries up or runs off. The microporous membrane is often sandwiched between a protective outer layer (usually coated with a durable water-repellent) and a fabric inner layer that provides comfort.

Paramo waterproof trousers are made using Nikwax Analogy fabric, which works differently. This doesn’t have a microporous membrane; instead, the fabric is 'directional' and works a bit like an animal’s fur to direct water away from the body.

Generally, overtrousers are to be pulled over the top of walking legwear for short periods during downpours, so they are designed to be highly waterproof rather than really breathable (unless you splash out a bit more money). 

Berghaus and Rohan's waterproof trousers scored five out of five stars for waterproofness and four out of five for breathability in our overtrousers survey of owners. Craghoppers is an excellent middle ground. Owners awarded their Craghoppers waterproof trousers three stars for breathability and the full five stars for water resistance – and paid considerably less for their pair. 

Shop Berghaus waterproof overtrousers

Shop Rohan waterproof overtrousers

Shop Craghoppers waterproof overtrousers

How easy are the overtrousers to get on and off?

If you’re caught out in a sudden storm, you need to be able to slip into your waterproof trousers speedily. Nobody wants to fiddle with uncooperative zips and tight ankle openings, or worse, needing to take off your boots and stand on one leg while pulling them on.

Check that your trousers come with leg zips (which go up to at least the knee) and an elasticated waistband so that you can get them on quickly over your walking boots. Be sure to test them out before you buy.

Should you go a size up in waterproof trousers?

Often, overtrousers are already generously sized to ensure they can fit over your hiking gear. But don't assume. It's always best to try them on first – preferably with your walking trousers underneath – to check they fit. You need plenty of room to bend your legs when walking or climbing. Shaped or articulated knee sections can help your knees bend more freely for unrestricted movement.

Once they’re on, Velcro ankle tabs can help to provide a tight seal around your boots or shoes to protect you from wet vegetation or the occasional puddle splash. A drawstring inside the waistband is a good idea, too, as it means you can tighten it up for a snug fit and to keep the rain out.

How should I care for my waterproof trousers?

While washing your trousers too regularly can reduce the waterproofing, you should clean them when dirty. This is because dirt and oils (such as those from sweat and sunscreen) also reduce the water-repellent coating’s effectiveness.

First, brush off any dried loose mud before ensuring all fastenings and flaps are secured. Check the label, as each item may have different instructions. If you're allowed to wash in the machine, ensure there's no residue of laundry detergent or fabric softener in the drawer. Then wash your trousers with liquid soap (not regular detergent) or a cleaner specially designed for waterproofs to remove dirt and oil. Don’t use fabric conditioner, as this may contain oils or fragrances that stay on the fabric.

If you still find they’re not as waterproof as they used to be, you could try topping up the water-repellent effect using a wash-in re-proofing product from outdoor retailers.