Waterproof fabric has been around for a long time; so long in fact that most of us never stop to consider what life would be like without it. Take a moment to consider what a boating trip, walking the dog on a drizzly day or working on a construction site in March would be like without some form of waterproof material?
Essentially waterproof fabric is any material that has been treated; allowing it to repel water while still letting vapour pas through. According to Innovation for Extremes the first attempts art waterproof clothing was made by the Aleut American Indians who used dried seal or whale intestines which they sealed with animal glues to create kamleikas (a kind of semi-transparent rain coat).
Luckily for us all sailors started experimenting with linseed oil – coating their sailcloth with it in the 15th century in an attempt to make it waterproof. Having moved away from animal intestines matters continued to improve to the point where G. Fox of London manufactured the first raincoat (called Fox’s Aquatic) in 1821.
Another famous example is that of the original Mackintosh rain coat – the only problem with these coasts being that fact they not only let no water in, but also let none out. This problem meant that the coats collected sweat and very uncomfortable to wear.
How it Works
Today most waterproof fabrics have been treated with a laminate or coating of, for example, PU (polyurethane), rubber or PVC (polyvinyl chloride) or wax to make it water repellent, while still allowing water vapour to pass through.
A fabric’s water resistance i.e. the level to which it repels water, “is measured, in mm, which can be suspended above the fabric before water seeps through”, while it’s breathability (or vapour transmission rate) is “measured by the rate at which water vapour passes through, in grams of water vapour per square meter of fabric per 24 hour period (g/m2/d)”.
According to GO Outdoors a garment is judged to be 100% waterproof if it meets the British Standard of 3 PSI (Pounds per Square Inch), which can withstand 1500mm of pressure. Today most types of water resistant jackets and trousers can withstand up to 2000mm and more of pressure and should keep you and yours dry throughout the day.
When selecting waterproof clothing be sure to check for the following:
- Does it have the appropriate waterproof rating for the conditions you want to wear it in?
- Is it durable?
- Do you need a thick coat for example, or a lightweight one?
- Look at the fit – a waterproof item that’s too small will be uncomfortable while one that is too large might let water in
When buying waterproof gear it’s important to look for quality items that will not only meet your specific needs, but will be of a quality that will endure.