Comment choisir sa veste imperméable ?

How to choose a waterproof jacket ?

The trail jacket is one of the items of equipment that should be chosen according to several criteria, because it can be decisive and a precious ally during your trail outings and races.

The jacket is an essential piece of equipment for trail runners, and race regulations (such as the UTMB®) even require a waterproof jacket with a hood and a minimum of 10,000 Schmerber.

The main role of a trail jacket is to protect you from the elements while remaining breathable. There are three levels of protection on a waterproof trail jacket:

a windproof trail jacket protects you from the cold when the wind picks up, especially when you're sweating. A windproof jacket protects you from the cold air and therefore indirectly provides warmth. A waterproof jacket is windproof, but a windproof jacket is not necessarily waterproof.

Water repellent:
water repellency is the property of a fabric that water slides off and does not penetrate. A water-repellent product will only protect you in drizzle or snow.

the waterproofness of a membrane is measured in Schmerber and it is considered waterproof from 10,000 Schmerber. At Raidlight, we have chosen to use an MP+ membrane (similar to Gore Tex) which is a technology specially designed to protect trail runners from rain and all types of bad weather.

For example:

- A 1,000 Schmerber jacket: can withstand a light shower for 1 hour.

- A 2,000 Schmerber jacket: can withstand a medium downpour for 2 hours.

- A 5,000 Schmerber jacket: can withstand average rain for 3 hours.

- A 10,000 Schmerber jacket: can withstand heavy rain for 2 hours.

- A 15,000 Schmerber jacket: can withstand heavy rain for 3 to 5 hours.

- A 20,000 Schmerber jacket: excellent protection in very heavy rain for several hours/several days.

- A 25,000 Schmerber jacket: excellent protection in very heavy rain and extreme conditions for several hours/several days.

The better the membrane, the better the waterproofing and the faster the moisture evacuation.


The breathability of a trail jacket is its ability to wick away perspiration. This criterion is decisive for staying dry during physical effort. Trail running involves physical effort on your part, and therefore more perspiration, which needs to be able to evacuate naturally. With breathable fabrics, you can avoid the unpleasant sensation of sticky, damp clothes during your outings.

There are several ways of measuring the breathability of a product. Here are the two most commonly used measurements:

The MVP (Moisture Vapour Permeability) measurement calculates the amount of water (in the form of vapour) that the fabric lets through in 24 hours. The higher the value, the more breathable it is. MVTR is expressed in gr /m2 / 24 h:

MVP 5 000 = garment not very breathable

MVP 10 000 = breathable garment

MVP 20 00 = garment with very good breathability

MVP 40 000 = garment with excellent breathability

MVP 60 000 = extremely breathable garment

This index is used by most equipment manufacturers.

The RET (Resistance Evaporative Transfer) index measures a fabric's ability to allow water vapour generated by the body (perspiration) to escape. Since RET is a resistance index, the lower it is, the more breathable the garment.

RET above 20: non-breathable

RET between 12 and 20: slightly breathable

RET between 6 and 12: breathable

RET less than 6: very breathable

This index is mainly used by American brands.

To find a trail jacket that meets all your needs, it's advisable to choose a model with practical details that match your usage habits.

- Hood: most waterproof jackets have a hood to protect your head and neck from the rain.

- Waterproof pockets: whether they're inside, side or centre pockets, you generally need to keep a few personal items with you. With waterproof pockets, your car keys or phone can stay dry throughout your sports session. You enjoy the convenience of keeping these items close to hand, with the assurance that they won't be damaged during your outing.

How do I look after my waterproof jacket?

For many people, buying a waterproof jacket is a real investment, and requires special care to ensure that it retains its technical qualities to the maximum. As a general rule, we advise against washing a waterproof jacket too frequently, as each wash reduces its waterproofing properties. We don't even recommend putting them in the washing machine, as the cycles very often damage the fabric and membrane and deteriorate the technology.

Once you've finished your outing, leave your jacket to dry in the open air on a hanger or chair. If you've sweated a little, you can rinse it in the shower with cold or even lukewarm water. If you've sweated a lot or if your jacket has a few stains, you can rub it gently with black soap or Marseille soap.

Some washing machines have a sports and/or hand wash cycle. If you decide to put your waterproof jacket in the machine, here are a few steps to follow:

- Close all zips and pockets (after emptying them). Also remember to loosen the straps and elastic parts.

- Use a little less detergent (waterproof detergent if possible) than usual to avoid residue.

- Set the spin cycle to the minimum setting to avoid damaging the waterproof jacket.

To avoid unpleasant surprises, don't mix your jacket with clothes of different colours and fabrics. Make sure you don't fold your jacket too much when you put it in the washing machine, and limit the load.

Of course, forget the tumble dryer and drying on a radiator!

At Raidlight, we offer a complete range of waterproof jackets to suit all your needs, designed with MP+® technology (similar to Gore-Tex) which is both waterproof and breathable. Every product equipped with the MP+ membrane is durably waterproof, windproof and breathable, whatever the weather conditions.

The characteristics of the MP+® membrane are :

- A high level of waterproofness
- A high level of breathability
- Windproof
- Resistance to cold
- Durability

Raidlight waterproof jackets are designed to accompany you whatever the weather and whatever your objectives. The Ultralight MP+ is the performance waterproof jacket. Its lightness, waterproofing and breathability (25K/60K) make it the ideal ally for ultra trail running. Fitted with the MP+ waterproof and windproof membrane, the Top Extreme MP+ trail jacket (20K/20K) offers a number of technical and practical benefits, such as the watch port and silicone-coated shoulder reinforcements. It's the perfect companion from training to competition. The Raidshell MP+ jacket is both warm and waterproof. If you're looking for a versatile jacket that can take you anywhere, for any occasion, then the Explore MP+ (15K/15K) jacket is your new must-have.

All our waterproof jackets are approved for UTMB®, UT4M® and Diagonale des Fous® races.

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