The key element to choosing the correct foul weather gear in order to remain dry and comfortable in just about any weather and sailing conditions is to match the type of sailing you will be doing and the conditions you will encounter to the gear you choose.
What is Foul Weather Gear?
Obviously the main aim of wearing foul weather gear is to remain dry whatever the conditions and still retain ease of movement. Foul weather gear is essentially about water management and is basically a shell designed to keep water out (waterproof) and through the use of high-tech fabrics, move any moisture that may accumulate inside the garment to the outside (breathability).
Ful weather gear may consist of jackets, trousers in essence they are a shell designed to keep the water out (waterproof) and move moisture on the inside to the outside (breathability).
Foul Weather factors:
Rain, seas, wind and duration of exposure are the four components that make up foul weather. These factors all need to be taken into consideration when choosing the right foul weather gear. It goes without saying that the stronger and heavier the rain, seas and wind and the longer the duration is that you’ll be exposed for, you’ll be needing more substantial foul weather gear in order to keep dry.
What is the difference between “Waterproof” and “Water-Resistant”?
To help shed some light on the issue, we turned to Wikipedia, which describes them as one and the same: “Waterproof or water-resistant describes objects relatively unaffected by water or resisting water passage, or which are covered with a material that resists or does not allow water passage.” In fact, there are differences between the two, and the applications for each vary. In a nutshell, “waterproof” means no water in, no water out. To be entirely waterproof, the surface must be completely impervious to water, and provide a high level of sustained water protection during the harshest conditions and under a certain level of pressure.
Although different manufacturers use differing test standards, any recognised brand of foul weather gear will not let any water through the material if it’s been labeled as “waterproof”.
Waterproof/Breathable: Certain waterproof fabrics contain a breathable membrane woven within the fabric, making them both waterproof and breathable. Waterproof, breathable fabrics help regulate heat and release moisture, and are recommended for high energy activities to dissipate heat and moisture.
Water-Resistant: Water-resistant (sometimes labeled “water-repellent”) fabric is coated with a finish such as DWR that is resistant but not impervious to penetration by water. Water-resistant fabrics will often bead up rainwater, forming drops on the surface. Water-resistant fabrics will provide protection from limited precipitation. Though water can saturate the fabric with harsh exposure, a water-resistant treatment will prevent moisture from seeping through the fabric. Clothing made from these fabrics are generally not considered to be foul weather garments.
Waterproof/Nonbreathable: If your foul weather gear is insufficiently breathable, you will get wet from the inside due to trapped perspiration. Since water is significantly more thermally conductive than air, wet clothing can be significantly colder than dry clothing. Any activity done while wearing these quickly lead to a build up or moisture (sweat) inside the gear.
What Breathability Means
Breathability is the layman’s term for moisture vapor transmission rate (MVTR), which is the measure of how quickly (or slowly, if at all) moisture passes through a fabric or other substance. It is usually measured in g/m²/day, or the mass of moisture that passes through a square meter of fabric in 24 hours.
You need to remember however that fabric breathability can halt or slow for three reasons:
1. Moisture may not move through the fabric fast enough. If this occurs, you will get wet from the inside via trapped perspiration. In dry environments, most “breathable” fabrics work well. In semi-humid environments, waterproof-breathable fabrics struggle. In very humid environments, nothing is going to keep you dry, sorry.
2. The “outside” humidity is too high. If the outside air is nearly saturated with water vapor already, there is simply no capacity for it to absorb additional vapor generated by you. When you perspire, it remains next-to-skin, unable to evaporate.
3. The fabric can “wet out,” or become saturated with water. When this occurs, usually due to the failure of a durable water repellant (DWR) finish, the outside humidity is essentially 100 percent. Moisture on the inside of the fabric cannot pass through these saturated spots. And, in fact, if humidity inside the jacket is less than 100 percent, then moisture can transmit into the jacket from these saturated spots, since it’s actually less humid inside than outside the fabric.
Waterproof Breathable Fabric Choices
The key component of your foul weather gear fabric is a coating or membrane that does the technological trick of blocking water out while also allowing water vapor (sweat) to escape.
Coated: Hydrophilic Fabrics
These are made from a solid hydrophilic (water-loving) polyurethane (PU) coating that is applied (think of it as paint spread on a wall) to the inside surface of the material (outer shell). Moisture on the inside of gear is attracted to the coating. The moisture vapor transport occurs by ‘molecular wicking’: the water molecules are first absorbed to the surface of the hydrophilic coating, then they move to the next molecule, and so on. This process continues through the coating until the water molecules emerge on the other side (outside). The water molecules are drawn from the moist, higher temperature of the inside of the gear to the relatively cooler and dryer outside.
Jackets will usually have an inner hanging liner (nylon and/or mesh) to protect the coating from abrasion. Dinghy smocks generally do not.
Coated fabrics work well, but do not pass as much water vapor as laminates and can wear away in areas of high chafe/wear over time. Advantages are solid performance at a lower price.
Laminate: Microporous Fabrics
The core of a waterproof breathable laminate is its membrane. These membranes are made from polytetrafluoroethylene (ePTFE) – widely know by its DuPont brand name: Teflon. These membranes are amazingly thin, and estimated to have 9 billion pores per square inch. Water vapor (perspiration) is drawn through these pours from the moist, higher temperature of the inside of the gear to the relatively cooler and dryer outside. Water on the outside of the material do not pass through the membrane due to the membrane’s ‘surface tension’ which cause water to bead up into drops too large to pass through the pores. Think of how a drop of water beads up when dropped into a Teflon pan – stays round and does not spread apart. Which is different than the common misconception that the pores are too small for liquid water to pass through.
The thin membrane is laminated between a durable outer material and a thinner inner scrim material (three layer laminate) so that it is protected from abrasion giving it the best durability of any waterproof breathable material. Laminates are the most effective at moisture transport, and carry a higher price tag to go along with the higher performance. Gore-Tex dominates this category and is widely held as the best. Over the years other fabric manufactures have been developing similar fabrics that come very close to Gore-Tex’s performance (some say a few are just as good in some circumstances).
Fabric Finishes – Durable Water Repellent (DWR)
All foul weather gear has a durable water repellent (DWR) finish on the outside of the material. This ‘water repellent’ finish causes water to bead up and roll off the outer fabric.
Maintaining the DWR finish of your gear is critical if you want to maintain the maximum breathability. When the DWR wears off, the surface fabric will ‘wet out’ (saturate). The underlying waterproof membrane or coating will still keep water out, but the saturated surface fabric slows the movement of sweat vapor to the outside. This reduced breathability can lead to moisture build up inside your gear, even making it feel as though it is leaking. Additionally, as water evaporates from the wet fabric, it cools, which can draw away body heat and leave you less warm or chilled.
The more environmentally friendly DWR finishes now in use wear off faster than older DWR products. Thus, regularly reapplying a DWR treatment should be part of your foul weather gear maintenance routine. When water stops beading up on your gear, its time to reapply more DWR.
How Should Foul Weather Gear Fit?
You want your gear to fit properly, be flexible, and be comfortable. If possible, try different types until you find the one that is best for you. Operate the closures at the wrists, ankles, and neck to make sure they are snug. Look for double inner and outer wrist closures that keep water out, and still allow you to adjust for ventilation. Comfort around your face is especially important. Front closures with gutters or Velcro storm flaps to funnel water away from zippers are a plus. So are heavy-duty YKK zippers that won’t rust or corrode.
Other features to consider are underarm grommets for ventilation, cargo pockets, fleece-lined handwarmer pockets, elastic shoulder straps, chest pockets on trousers, and roll-up hoods. Reflective tape is an added safety feature.
Coastal and more so, offshore and ocean gear is full cut throughout to provide you freedom of movement and room for multiple under layers that will keep you warm. This is to say that you may feel they are a bit too loose when you first try them on, but that is the fit you generally want. Sleeve lengths will be long in order to allow you to raise and move your arms unrestricted when fully geared up with multiple layers. Sleeves will generally cover a portion (or most) of your palms when your arms are at your sides. Tighten the external Velcro adjustments on the sleeves if you desire they stay up at the wrists. Trouser leg lengths will be longer too. This is to ensure you can bend and crouch unrestricted when geared up. If you are not wearing your deck boots with your trousers, you will probably need to tighten the Velcro adjustments at the ankles to keep the trousers from sliding under foot.
Inshore, keelboat racing and dinghy racing gear is roomy but with a more athletic fit. They are not too loose or baggy, but do offer enough material in the cut for you to have unrestricted movement when geared up with an under layer. Sleeve and trouser lengths are longer than street clothes (not as long as coastal, offshore or ocean gear) and may require the use of the outside Velcro wrist and ankle cinches to keep them off the hands and from under your heel.
Light Inshore gear will be more of athletic shore wear cut. Sleeve and pants lengths do not generally require Velcro cinches to keep them in place.
Dinghy racing gear needs to be long enough in the arms and legs so that you can raise your arms and squat with the seals cinched. Be sure that the seals cinch snuggly around your neck and wrists. If not water will leak in.
Foul Weather Gear Categories:
Ideal for extended and extreme ocean use over consecutive days and weeks in the harshest weather and boat abrasion conditions, and built to stand up to these abuses again and again. This is THE gear relied upon by professional sailors for events like the Vendee Globe or Volvo Ocean Race.
Similar to ocean gear, offshore is for ocean sailing over consecutive days and weeks. The materials and features offer great protection in extreme conditions but are slightly less robust making for a better price point for the recreational offshore sailor who still requires excellent protection.
Appropriate for medium distance passage making, and every day near shore/harbor sailing. Coastal gear is designed to be worn for days on end while providing you good protection and comfort.
A good choice for near shore/harbor sailing, and will keep you dry all day long in poor weather, but not designed to protect against extreme weather conditions. This foul weather gear is also great for onshore wear on rainy and blustery days.
These jackets and waist pants (no trousers with suspenders here) are perfect for keeping you dry in the poor weather as you seek a protected harbor. Popular on and off the boat, and are great to always have in your day bag in case of a passing squall.
Note: Not included here are dry suits and wet gear (wet suits) that are designed for protection if submersed in the water.
Dinghy racing foul weather gear is waterproof and breathable and designed to keep you dry from rain and spray when sailing (not if you capsize/fall into the water), and designed for day sailing. Dinghy smock tops are popular on all dinghies and even small keel boats. They are lightweight and easy to move in. The neck, wrists, and waist all have adjustable seals to keep water/spray out (some less expensive smocks have an elastic waist and not an adjustable waist seal). Trousers have adjustable ankle closures or seals that can be cinched around dinghy boots.
Some final tips:
- Don’t buy a jacket with an internal harness. You can’t inspect the harness for wear. Get loops sewn onto the outside of your jacket (by the manufacturer if possible) to attach your harness to.
- Always take you foul weather gear off the boat and wash and dry it carefully. Check the pockets.
- Buy a couple of polar-tech “beanies”. You lose about 10% of your body heat through your head.
- Wear a baseball cap over your beanie when wearing your hood up. If you don’t have a cap on, when you turn your head, the hood doesn’t turn, and you can’t see properly. A cap is especially useful if you’re steering with a tiller.
- In heavy weather keep your harness permanently attached to your jacket so you can put both on at once in an emergency.
- A good sailor takes staying warm and dry very seriously.