For ski-wear manufacturers these terms can mean specific things and to the public it can mean something different.
If you don't have the time to read the full article, read the bullet points below, but I suggest you read on for a fuller explanation.
- FACT, A waterproof label does not mean its 100% waterproof
- FACT, the devil is in the detail, look at the all important numbers associated with the word "waterproof" and "water resistant", E.G. waterproof to 5,000mm.
- The numbers mean a great deal and are ignored at your peril.
- The lower the number, the lower the water resistance
- Numbers are usually between 500mm to 20,000mm +
- Low number = suitable for light rain/light dry snow for short period
- High numbers = suitable for heavier rain/snow for longer periods
- Only a rubber suit is 100% waterproof in all conditions and you would be wet with sweat. Everything is a compromise.
- Sealed seams are just as important, if seams are not sealed, then they WILL leak in any wet conditions. It may not be possible to seal certain fabrics due to being stretchy, other times its down to cost.
- Cost is a big basic indicator, low cost usually means a lower spec garment.
- Which is why some ski-wear costs £400 and some £40, not everybody needs the highest specification gear.
- Given enough time even the best gear will eventually leak in the most adverse conditions.
- If you are a fair weather/casual skier, lower spec gear is a great choice but if you are a person that skis in all weathers, you need higher spec kit.
Water resistance: what does this mean? Well some customers assume wrongly that you can get a good soaking wearing anything with a "waterproof" label and the garment will keep you dry, WRONG, and if the jacket or trousers has let in water, its not doing its job, so not fit for purpose, WRONG again. I will explain.
Every outdoor garment is designed for a purpose and those purposes are not all the same. There is no, One standard, One level of waterproofing and this is why its a confusing area.
Water resistance: It simply means that it will "resist" water penetration to some degree. Does that mean its 100% waterproof, No not a chance, It means it will resist water penetration for a while. But how long is that? How long will it resist water penetration, see the ratings system below. As they vary a lot as some fabrics are much better that others.
You often see phrases like, Waterproof to 5,000mm or a similar number e.g. 3,000, 10, 000 , 15,000, etc, what does this mean: This is a test of water resistance, its a numbered system and is used to allow users to judge one product from another for suitability. This means the fabric has been tested and found to pass a certain degree of water resistance. In the case of 5000mm, this refers to 5000 millimetres. Ok, so what does that mean in plain English please. It simply means that water has been forced onto the fabric in a 1 inch tube from a height of 5000mm, (5 metres) for a 24 hour period and found to have passed the test. Other numbers simply indicate the fabric passed a test that was more severe (higher numbers 10,000, 15,000, etc) or passed a lower test (3,000, 2000, etc). The higher number gives higher water resistance and therefore better performance in bad weather, lower numbers mean less performance in wet weather.
Put simply, the higher the number the higher the water resistance. There is always a compromise between cost/performance and suitability. Remember the higher the rating, the more you can sweat, so you need high breathable fabric too. As sweat is water vapour and has to escape otherwise you will be wet with sweat.
Anything else to consider? Yes Seams. What about seams? That they are sealed or not sealed, it has great importance.
Some clothing are advertised as having all seams sealed, this means that every outer seam on the fabric is sealed from the back to prevent water ingress through the seams. Some garments state that only the important seams are sealed, on tops of shoulders, etc, this is to lower costs. Many potential customers do not want clothing that will perform in all weathers or severe weather as they are not severe weather skiers and do not want to pay for such a garment if it is of little use to their circumstances. Some fabrics cannot be taped at all due to the nature of the fabric, as it maybe stretchy or puffy, preventing the use of tape. Garments made from these fabric and construction are not designed for prolonged wet weather and should be used accordingly.
Conclusion: There has never been a better time to buy high quality ski-wear for the lowest cost but customers have to be aware of the various types of garments and fabrics in use and use them accordingly. So in real terms, what does it all mean. Well If you have a 10,000mm water resistant jacket and its raining all day, will it leak? Quite possibly, Its impossible to tell, but what I can tell you is that if the 10,000mm of saturation is reached while you are wearing it, then yes it will. If it doesn't it wont. This does not mean that the garment is not water resistant or not fit for purpose, it means it was subject to conditions beyond its water resistance limit. This is why you sometimes see officials and stewards wearing plastic ponchos at sporting events, its one of the only methods of trying to guarantee to stay dry. You will sweat bucket loads though!
This is why there are so many levels of water resistance. Its about weighing up the pros and cons for your particular set of requirements. If you are a ski instructor and you have to stay on the slopes for 8 hours every day, every week for months, whatever the weather. Then you need the highest spec fabric, taped seams which costs a lot of money. Most holiday skiers do not need that level of protection and therefore do not need to spend £300+ on a jacket of such high quality. If the weather is terrible you take refuge. You have to decide what works for you. You pay your money and make your choice. My wife is a fair weather skier, doesnt like to ski much in the snow or rain, so for her clothing based on a 5,000mm fabric will be more than adequate for her. My 28 year old son will ski all day, every day and in all weathers. he can use the same lower spec gear but if the weather turned wet, he will run into trouble. He can take that risk and get away with it, as most Alpine days are dry, but if it turned bad for days, he is screwed. Choose the correct level of gear to satisfy your requirements.
So if you are using a garment (jacket or trousers) that has a low water resistant threshold in adverse wet conditions, it will leak sooner rather than later and that's a fact
I hope this helps explain water resistance and water-proofing in skiwear.