We put five of the best to the test
This area is commonly elasticated for extra comfort. A drawcord allows extra control of fit, while Velcro tabs, press studs or belt loops allow further enhancement of fit. The ability to attach braces is ideal for scrambling or mountaineering.
The longer the zip, the easier it is to put on overtrousers while still wearing boots, or even crampons. This is also an area that can easily leak, particularly at the knees when the zip flexes. Water-resistant zips may keep some water out, but as they may still leak they are often fitted with an internal flap that is designed to channel away any water that enters this area. External storm flaps are ideal, but they are heavy and bulky.
The area on the inside of the ankle takes a hammering and rapidly wears out from being scuffed with boots, crampons, rocks and undergrowth. Look for an extra panel of material here if you are going to be really hammering this area on mountain walks.
In general, higher-priced overtrousers use more breathable 3-layer laminated fabrics, which will reduce the likelihood of condensation forming on the inside of the fabric. Mesh linings improve comfort, as any condensation is held away from the body, but such linings make a trouser heavy and can snag when you are putting the trousers on over boots. A lightweight trouser may use 2-layer or 2.5-layer fabrics that tend to show condensation a little more.
Overtrousers can often be baggy, but if the knees are articulated they can be designed to fit a little closer. Look for a seam around the knee area and a slightly angled shape in the leg if you want a closer fit. The calf may have some Velcro tab adjustment so it can be tightened down a little and there may be a drawcord, Velcro tab or press stud at the ankle cuff. Some trousers come in a choice of leg lengths.
Even the best waterproof and breathable fabrics allow condensation to form, so it is important that you can increase ventilation between showers. A trouser with long side zips and two or three zip pulls will allow extra ventilation at the calf, knee or hip.