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How to choose a wetsuit

Whether you’re a surfer at almost any break outside of the tropics, a triathlete swimming in open water, or a paddler seeking an extra margin of safety, a wetsuit is indispensable. Wetsuits keep you comfortable in cool or frigid water by holding a thin layer of water next to your skin that your body warms up, which creates a thermal barrier.

The range of options and opinions out there can seem overwhelming, but you can zero in on your ideal wetsuit by thinking about a few things:

  • What’s the water temperature?: Get the right wetsuit thickness for the temps you’re in.
  • What activity are you doing?: Surfing, swimming or paddling require unique wetsuit designs.
  • Finding the right fit: A wetsuit that fits well keeps extra cold water from getting in (“flushing”) and replacing the body-warmed water already inside.
  • Wetsuit design features: Learn how zippers and seams can affect warmth.
  • Helpful accessories: Gear to complete the ensemble and keep you warmer.

Water temperature and neoprene thickness

Surfer with icicles on wetsuit

The magic ingredient in wetsuits is neoprene, a stretchy synthetic rubber that finds its way into all kinds of things from hose gaskets to high-fashion clothing. The neoprene used in wetsuits is “foamed” with nitrogen to improve its stretch and insulating qualities.

While most neoprene manufactured today is petrochemical-based, some brands use neoprene made from a limestone-based manufacturing process – this process uses less petroleum. Some wetsuits also use dope-dye yarn, which helps lower the carbon footprint while providing better fade resistance.

Neoprene thickness

The water temperature where (and when) you surf, swim or paddle heavily influences the thickness of suit you should choose. Neoprene comes in a range of thicknesses – the thicker the neoprene, the warmer the wetsuit.

Where you see a single number for a wetsuit (e.g., 2mm), it means that one thickness of neoprene is used throughout. Two numbers (e.g., 4/3) mean the wetsuit has two thicknesses of neoprene. The thicker material goes around the core for warmth and buoyancy, and the thinner material is for the arms and legs for mobility. Some wetsuits even use three or more different thicknesses.

There are lots of temperature guides out there, and things like wind, air temp, personal preference, and how long you’re out for can influence what wetsuit thickness is right for you. Here are some general guidelines to start:

Wetsuit temperature chart

Water temperatureNeoprene thicknessTips
8°C and under6/5mmHooded full suit, plus add 7mm boots and 7mm mitts (warmer than gloves)
8–12°C5/4mmHooded full suit, plus add 5mm boots and 5mm gloves)
9–13°C4/3mmHooded full suit, plus add 3mm boots and 3–4mm gloves
11–14°C4/3mmFull suit, plus add 3mm boots and 1.5–2mm gloves. Might also want a hood.
13–18°C2mm or 3/2mmFull suit
17–20°C2mmFull suit, spring suit or farmer John/Jane
18–21°C2mmSpring suit or shorty
21–23°C1–2mmSpring suit or shorty, or a neoprene top with shorts
23°C and upNot neededSkip the wetsuit – go for a rashguard to protect you from the UV rays

Some wetsuits designed for colder water are lined with an extra layer of soft fabric inside; this adds a bit more warmth without adding bulk from thicker neoprene.

“On the coldest days, we bring a bottle of hot water to pour into our wetsuit before going out. By starting with warm water, you save your body the need to warm up the trapped water in your suit. Make sure the water isn’t too hot!” – Antonio L. from Surf the Greats

Wetsuits for different activities

How you plan to use your wetsuit plays a big role in deciding what wetsuit to choose. Learn about your options for surfing, triathlons and open-water swimming, and paddling.

Wetsuits for surfing

Surfer running into the water

Surfers have the widest range of wetsuit styles to choose from, and there are types designed to cover every temperature scenario from Indonesia to Iceland.

MEC Fusion Shorty wetsuit

Shorty wetsuits

Also known as spring suits or shorties, this style is cut off at the knees and elbows. (Note that “spring” is definitely more southern California spring than Canadian spring.) The relatively thin material and short arms make for easy paddling. Great when it’s just a bit too chilly to surf in a swimsuit and rashguard.

MEC Fusion 4/3 wetsuit

Full suits

Also known as steamers, these are commonly worn at surf breaks around the world. Full suits are generally thicker and more resistant to flushing than shorties. Generally good for summer sessions in the southern Great Lakes or on Canada’s east and west coast. Paired with a hood, gloves and booties, many surfers can also wear a 4/3mm full suit well into the shoulder seasons.

Xcel hooded full wetsuit

Hooded full suits

Full suits with built-in neoprene hoods made for the coldest conditions surfers are likely to encounter. Some have an inner fabric lining for added warmth. A 5/4 hooded suit can work year-round for west coast spots like Tofino, and Atlantic breaks like Lawrencetown in Nova Scotia, and almost all but the coldest times of year on the southern Great Lakes. Go thicker (like a 6/5/4) for winter on Lake Superior or similar character-building temps.

“If you can only afford one wetsuit, I’d say start with a 4/3mm as it’ll be versatile and work well into fall and in early spring. But if you plan to surf in winter, make sure you wear at least a hooded 5/4 and a pair of booties and 7mm mittens.” – Antonio L. from Surf the Greats

Triathlons and open-water swimming

In addition to warmth, wetsuits for triathletes and open-water swimmers provide buoyancy and a streamlined profile. Swimmers can shave off seconds per kilometre in a well-fitted tri suit, so races regulate their design and use. Full suits with rear zippers are the most popular style, though some athletes (particularly strong swimmers) go for armless designs for improved mobility at the cost of insulation and buoyancy.

Tri suits differ from other wetsuits in a few ways:

  • They have a slick outer coating that reduces drag in the water.
  • They have thicker, buoyant panels of neoprene around the core and thinner, stretchy panels in areas where mobility is most important (like arms and legs).
  • Triathlon wetsuits are super flexible, which comes at the cost of durability and ease of use. Putting these suits on is a technique in itself, and you need to take care to avoid nicking or tearing them in the process.

Competitive vs. recreational tri suits

Unlike wetsuits designed for surfing, neoprene thickness is generally less of a deciding factor when you’re open-water swimming. Instead, look at design features connected to speed and your swimming skill level.

If you’re goal-oriented and want to be competitive at triathlons and open-water swim events, choose the most advanced wetsuit that fits your budget. More advanced suits often have tailoring details to improve efficiency and promote good stroke mechanics. Some add subtle forearm ridges to increase stroke power, or tailor the arm fabric to encourage a high elbow at the top of your crawl (many swimmers drop their elbow as fatigue sets in). High-end suits also help you keep a good body position in the water through the careful positioning of different thicknesses of neoprene.

If you’re a recreational open-water swimmer or just testing the waters at your first triathlon, an entry level suit should cover all your needs.

Paddling

Unlike surfers and swimmers, stand-up paddleboarders and kayakers have the option of wearing waterproof-breathable layers like drysuits, dry tops and paddling jackets. So why use a wetsuit while paddling? Affordability is a big factor. While they don’t provide the same cold-water safety as drysuits, paddling-friendly wetsuits are a fraction of the cost and (when combined with a paddling jacket) offer effective protection over a fairly wide range of temperatures.

“I always use a thicker 5/4mm wetsuit on a river SUP, as I appreciate the extra padding when I fall in rapids.” – MEC Ambassador tip

Farmer Jane and Farmer Johns

As a paddler, you’re (hopefully) expecting to spend more time on the water than in it, so the features you should look for in a wetsuit are different than surfers and swimmers. Arm and shoulder mobility is a key thing for paddling, so sleeveless wetsuits are recommended for most situations.

Full-leg sleeveless styles known as Farmer Jane or Farmer John wetsuits are ideal. This open-armed design makes them more prone to flushing than other wetsuits, but you can minimize this drawback by wriggling back onto your board or boat quickly. Pairing a sleeveless wetsuit with a thermal rashguard and dry top is a time-tested way for paddlers to boost cold-water protection.

These suits tend to be made of 3mm neoprene (often with 2mm lower legs). This thickness strikes a balance between being warm enough to give some protection if you take an unintended dunk in cold water, and light enough for longer wear outside the water in typical Canadian summer and shoulder-season weather.

Paddlers can also use neoprene shorts, pants and vests, all of which give versatile warmth without restricting mobility.

Fitting your wetsuit

Proper fit is critical for a wetsuit to do its job. To prevent flushing, you want your wetsuit to be as snug as possible without restricting mobility. Warning signs of a too-loose fit are folds in the fabric and bunching or excess material, often behind the knees and under the arms. A full suit should be snug at the wrists and ankles – it should take a bit of shimmying to get on.

At the other extreme, a wetsuit is likely too tight if:

  • The fit is painfully restrictive anywhere.
  • You can’t freely move your arms or legs.
  • It feels like it’s riding up in the crotch area (a sign the suit is too short).

“Use a plastic shopping bag over your foot to make it easier to slide on a wetsuit. As you put it on, stretch the legs thoroughly before you start working on the upper body area.

Keep your fingernails away from the suit, otherwise you can end up with holes. Try not to leave any areas bunched up for the perfect fit.” – Antonio L., Surf the Greats

Design features to look for

When you’re looking at wetsuits, you’re going to come across different zipper placements and seam options, some of which affect the price. Here’s the scoop on some design features:

Wetsuit zippers

Zipper placement can make a difference to how warm the suit is, and also how easy it is put on or take off.

Full front zippers: Make a wetsuit super easy to get into, but also the most prone to flushing. They can be uncomfortable for surfers since you spend a lot of time on your front paddling.

Back zippers: Not quite user-friendly as front zips, but much more resistant to flushing and common on lots of wetsuit styles. The zipper usually runs from the base of the spine to the collar, and has a long strap attached so you can zip it up yourself.

Chest zippers: Compared to other zippers, this one might take a bit more effort to put on the first time, but the process quickly becomes natural. Chest zips have two main advantages over back zips: they’re more resistant to flushing, and they give you better mobility because the back of the suit is made of one continuous panel of neoprene (which stretches, unlike a zipper). Common on higher end surfing wetsuits.

Seams

The way neoprene panels are attached can affect the way the wetsuit feels and performs:

Flatlock seams: Often found in lower-priced wetsuits. They’re not totally waterproof, but they’re fine for wetsuits and neoprene accessories designed for warmer water. Flatlock seams are recognizable by a criss-cross stitching pattern visible on both the inside and outside of the seam.

Glued and blind stitched seams: Common in suits meant for cold water. Neoprene panels are glued edge to edge and then stitched with loops that don’t pass all the way through to the outer face. The interior stitching is usually backed with tape. The lack of through-holes means the natural waterproofness of the neoprene is preserved, greatly improving warmth.

Fluid-seam welds: Found at the high-end of the wetsuit performance (and price) spectrum. Welded seams are airtight and super low-profile, which gives you excellent warmth, waterproofness and comfort.

Wetsuit accessories

Surfer wearing hood, gloves, booties and wetsuit on a wave

A few neoprene accessories can help keep you in the water longer, and they go from handy to downright essential when water temperatures drop below 10°C.

Hoods

Hoods can make a huge difference in cold water and cold air. Accessory hoods typically have a bib or dickie (a neoprene collar that tucks under your wetsuit collar to reduce flushing). While not quite as effective as a full suit with built-in hood, a hood is a cost-effective way to extend the range of your 4/3 full suit. A brim helps keep water from running into your eyes.

Gloves and booties

Bare hands and feet go numb fast in cold water (which definitely cuts down on the fun factor). Booties keep your feet warm and also protect you from sharp nasties on the sea floor and shore. Thicker is warmer, but stiffer; thinner soles give you better board-feel than thicker (e.g. 5 mm+) booties. If it’s really cold, opt for mitts over gloves.

“The ankles of your wetsuit go over your booties, and the wrists go over your gloves or mittens. Roll up the sleeve of your suit before you put your gloves on so you can easily roll the sleeves over top.

To put the second mitten on, ask for help from a surf buddy or a stranger in the parking lot. Trust me, it must be hard being a lobster!” – Antonio L. from Surf the Greats

Rashguards

Often used as stand-alone surf and paddle wear in warm water. You can also wear rashguards under wetsuits to protect you from chafing, and they add a bit of warmth to any suit.