Windproofs - Buyer's Guide

Okay, we're going to get quasi technical. Insulation works by trapping a layer of air close to the body which is, in turn, warmed by your body heat and forms an insulating layer. If that layer of air is exposed to wind, the warmed air is stripped away from your body, you need to warm more air and the ongoing process makes you cold. That's what wind chill is all about, wind driving away that coating of warmed air and making you feel colder.

Wearing a windproof stops the process in its tracks, allows the already warmed air to lose heat at a much lower rate and effectively allows the insulation layers you're wearing to do their job. Quite handy really.

Even if you reckon we live in perpetual rain, it ain't strictly true. In reality most of the time we spend outdoors is maybe drizzly, maybe cool and breezy, but not actually wet. Well, not always. The big plus of windproofs over waterproofs, which are also windproof, is increased breathability. That means less sweat, more comfort. Add in a degree of water resistance and you can get away with wearing a windproof perhaps 90 per-cent of the time. If you run really hot, then you can maybe make that all the time.

It's common sense really, for maximum efficiency, you want a cut that prevents flapping and billowing that will move warm air around inside your clothing and decrease efficiency - the only proviso is that you don't want it so tight that it either compresses your insulation layers or impares your mobility, because you are planning to move about, erm, aren't you. A loose-fitting windproof will still provide a lot of protection, but snugger is more efficient and will work better with packs, harnesses and so on by reducing the amount of excess fabric.

You could argue, and I wouldn't necessarily disagree with you, that windproof jackets should be cut and featured like waterproof tops complete with hoods. Unfortunately the manufacturers don't generally see things that way - a lot of windproofs seem to be targeted at 'fast movers' like mountain bikers and runners and are cut short and with minimal features as a result. That makes them great for stowing away, but not so clever for regular all-day use. We like a hood and the odd pocket, but that's very much personal choice.

There are a few windproofs with more extensive features, Haglofs, for example, produced a Gore Windstopper jacket that's basically a full waterproof shell design made in a windproof fabric. And then there's 'soft shell'.

Ah, soft shell, a confusing sort of concept, but generally windproof or highly wind resistant with a more technical sort of cut. You won't go far wrong if you just think 'flash windproof' with price tag to match... As a bonus many softshells have some sort of stretch element to them, which can improve fit and efficiency.

You pays your money and... Windproof fabrics run all the way through from ultra-lightweight close-woven materials like Pertex, which usually feature at the lightweight end of the market, through to expensive, membrane-based fabrics like Gore's Winstopper and Polartec's Powershield laminates. On top of those, there are a fair few generic windproof fabrics based on synthetics with varying degrees of softness and water repellancy depending on the treatments used. And, of course, there's Ventile, which is densely woven cotton.

Anyway, here are a few examples:

• Pertex made by Perseverance Mills, Pertex is the original lightweight windproof fabric. Very light, good wicking properties, in its raw state it's not particularly windproof, or abrasion resistant but latest versions use a treatment called Shield to up water and abrasion resistance. Used by Montane, Rab, Buffalo and others.
  
• Parameta is again closely woven microfibre used by Paramo for their windproof clothing but also forming part of their waterproof garment system. When treated with a Nikwax DWR it's reasonably water resistant and completely windproof.
  
• Polartec Powershield has a stretch woven face bonded to a PU membrane which is approximately 98 per-cent windproof. Polartec says that the 2 per-cent permeability allows enough air to circulate to dramtically improve breathability over 100 per-cent windproof rivals. It works up to a point, but can still get sweaty in UK conditions.
  
• Gore Windstopper is a PTFE membrane laminated to various face fabrics. The membrane itself is waterproof but the seams aren't taped meaning that the garments made from it are technically only windproof and highly water resistant. Works well in cold, dry winter conditions, but breathability can let it down in the warmer, more humid UK mountain environment.
  
• Gore Windstopper Softshell is simply Gore's Windstopper membrane laminated to a stretch face fabric and with some sort of fleecy backing. The stretch gives good fit if the cut is right, but if you run hot, again you may have issues with breathability.
  
• Generic Windproof Things Lots of companies use their own windproof fabrics sourced from the same suppliers but with different names and descriptions - some, like Patagonia, have incorporated stretch qualities, others are closer to Pertex, but with a more natural, less shiny feel. It's hard to make a blanket judgement, but generally they rely on a close weave for windproofing and a DWR treatment for water resistance and are significantly cheaper than branded fabrics and membrane-based ones in particular.

Hopefully this article will have given you some basic pointers. The good news is that there's a load more advice on OUTDOORSmagic:

• Ask on the gear forum about general issues or specific items.
  
• Check the member reviews section for user experiences of kit.
  
• See OM editorial reviews on the front of the site for our impressions.
  
• Ask Richard Gear if you have a specific question you need answering.