Choosing a Lightweight Waterproof Jacket for Showers

Why the walking around Reading is hard on a jacket

A fortnight of dry weather can lull you into leaving the waterproof at home, and then a shower comes up the Thames Valley from the west and catches you halfway along an exposed ridge with nothing but a hedge for shelter. The countryside around Reading is full of exactly the sort of terrain that punishes a poor choice: the long, open climb towards Walbury Hill, the wind-scoured fields above Pangbourne, the bare stretch of the Goring Gap where there is nothing between you and the weather but a stile and a fingerpost.

The answer is rarely a heavy mountaineering shell. It is a lightweight waterproof you are genuinely happy to carry every day, because the jacket left in the car keeps nobody dry. When you are comparing options, three things matter more than anything else on the swing tag: packability, hood adjustment and breathability.

Packability: the real test is your daysack pocket

Manufacturers love to quote a packed size, but the number that counts is whether the jacket will go back into your bag while you are standing in the rain, wearing gloves, with a dog pulling at the lead. A jacket that has to be folded with the care of a parachute will end up carried in your hand instead, which rather defeats the point.

Look for a fabric in the 20 to 40 denier range. That is light enough to compress well but still tough enough to survive being pushed through hawthorn and blackthorn on a narrow bridleway. In a men's or unisex medium, anything between roughly 200g and 350g is realistic for a genuine waterproof. Below that, you are usually trading durability or features; above it, you start to notice the weight on a long summer day.

• Can you stuff it into its own chest pocket and clip that to a belt or shoulder strap?
• Does it squash into a 20-litre daysack side pocket without stealing room from your flask and sandwiches?
• Does the hood roll or fold away tidily, or does it sit at the back of your neck like a pillow?
• Does the fabric feel stiff and crinkly, or does it soften once it has been worn a few times?

A three-layer jacket usually packs slightly larger than a 2.5-layer one but lasts longer, which matters if you walk most weekends. If you only get out a dozen times a year, a well-made 2.5-layer will serve you perfectly well.

Hood adjustment: where cheap jackets give themselves away

This is the part most people ignore in the shop and regret on the hill. A hood that cannot be adjusted properly will either flap in the wind, letting rain drive straight down your neck, or sit so far forward that you cannot see your feet on a muddy descent.

You want at least two points of adjustment, and ideally three: a rear volume adjuster to pull the hood in to the size of your head, and drawcords at each side of the face to close the opening down. A wired or stiffened peak is worth its weight in gold in a headwind, keeping the rain off your glasses and letting you look up at the view rather than at the puddles.

Check the collar height too. A high collar that zips up over your chin, with a soft chin guard behind the zip, makes a real difference when the rain is coming in sideways on the open fields between Aldermaston and Beenham. Try the hood on over a cap as well as on its own — many of us walk in a cap for most of the year, and a hood that will not fit over one is a nuisance.

Breathability: keeping the inside as dry as the outside

A waterproof that does not breathe simply moves the damp from outside to inside. You climb steadily out of the Thames Valley, warm up, and within twenty minutes your baselayer is wet through. In cool weather that is uncomfortable; on an exposed ridge it is a genuine chill risk.

Breathability is usually quoted as a moisture vapour transmission rate, and higher numbers are better, but do not get too hung up on the figures. What matters in practice is the whole system:

• Pit zips or deep chest vents you can open on a climb without letting the rain in.
• A decent durable water repellent finish on the face fabric, so the outer surface beads rather than soaking up water and blocking the membrane.
• A sensible baselayer underneath — merino or a synthetic wicking fabric, never cotton.
• Avoiding the common mistake of wearing the waterproof over three other layers on a mild, drizzly day.

Remember that a DWR finish fades with use and dirt. A wash with a proper technical cleaner, followed by a low tumble dry, will often bring a tired jacket back to life far more cheaply than replacing it.

Matching the jacket to the walk

For a gentle afternoon on the Thames Path or a loop around the Loddon Valley, a very light packable shell of around 200g is ideal — it lives at the bottom of the bag and you forget it is there. For a full day on the Ridgeway, or a winter circuit over the Chilterns where you might meet sleet as well as showers, a slightly heavier three-layer jacket with proper pit zips and a stiffened hood is the better companion.

If you walk in a group, consider how the jacket behaves when you stop. A shell you can pull on and off without removing your pack is worth far more than an extra gram saved.

A short checklist before you buy

• Weight: around 200g to 350g in your size.
• Packed size: fits a daysack side pocket or clips to your belt.
• Hood: two or three adjustment points, wired peak, high collar.
• Ventilation: pit zips or chest vents.
• Fit: room for a fleece underneath, but not so baggy it flaps.
• Pockets: at least one you can reach with a pack on.

Buy the jacket you will actually carry, try the hood properly in the shop, and a sudden Berkshire shower becomes a small inconvenience rather than the end of a good walk.