Wetsuits explained

When slecting a wetsuit it is easy to get overwealmed by the huge variety of options and the confusing details on each suits label. This article aims to give a little guideance on the areas you should be looking at when selecting a wetsuit (without getting into too much detail on specific material compositions).



How does a wetsuit work?

Understanding the answer to this question is vital in realising which are the key features in wetsuit design.

A wetsuit is designed to allow water into contact with your skin, but the to hold that water there, this allows your body to heat up the water within the suit which keeps you nice and warm. Warmer wetsuits will be thicker and have as few gaps or holes in them as possible. They must also be well fitting (body hugging) to ensure that when the water does get into the suit it is unable to move around and transfer the heat from your body.


What to look at when selecting a suit

When in a shop (or online) selecting a wetsuit there is a four step process to follow to decide which is right for you.

  1. Long or short 
  2. Selecting thinkness
  3. Identifying the effective seal of the wetsuit
  4. Selecting the right size

When selecting how warm you need a suit to be you must also consider the temperature, users resistance to cold and also the usage you require from it. Movement generates heat so more active sports will require thinner wetsuits than for less active sports.

For example swimmers will use thin suits that dont restrict movement and as they are constantly active they dont need so much insulation. In contrast, cold water scuba divers will need very thick suits as they are low mobility and spending a lot of time in the water.


1. Long or short

Wetsuits with long arms and legs will be warmer than short suits, but will also be more restrictive. Some winter wetsuits also have buit in hoods which will be even warmer.

Generally short suits are used in summer months (>20 degrees C) while long suits are used the rest of the year. 

Selecting the correct short suit is far less critical as in warmer conditions less temperature retention is required from the suit.


2. Selecting thickness

A thicker wetusit will be warmer than a thin suit, but will also be more restrictive.

Westuit thickness is measured in mm and is usually given as two numbers for example:

3:2 thickness wetsuit.

The first number refers to the thickness of the suit in the core body areas (chest and back) while the second refers to the thickness at the extremeties (arms and legs). Thinner material is used on the arms and legs as these areas are not so critical in the overall warmth of the person and it is where increased mobility is advantageous.

Most wetsuits start at 1 or 1.5mm and range up to 6mm (specialist suits outside these thicknesses are available).

For summer conditions 1-3mm is usually all that is required, while winter will often need 4mm+ suits to ensure that you can stay on the water having fun for longer.


3. Effective seal

This is how well the wetsuit is designed and built to reduce the amount of water that can flow through it.

This is mostly infulenced by: the type and length of zip, type of seams present on the suit and how effective the seals around the openings (arms, legs and neck) are.



Wetsuits come with three common zip styles:

1. Back Zip - Large vertical back zip with pull cord to allow for easy reaching. This is the easiest to get into and use, especially for less mobile people. However, the large zip length and break of neck seal can cause increased water flow through the suit.

2. Chest Zip - Small (generally horizontal) zip at chest height. Short zip area with neoprene behind it means minimal water travel through the suit. Can be tough to get into and out of.

3. Zipless - No zip, instead has layered pannels and bungee cord to ensure a tight fit is found. This is the warmest type of suit, with no zip area to let water through it has minimal water travel. Hard to get into and out of.



Wetsuits will generally have a combination of a few different types of seams as listed below (note this list is not exhaustive of all seam sealing techniques).

1. Stitched seam - most common in lower quality suits, strong connection but it introduces lots of small holes into the suit allowing for water flow.

2. Blind stitiched seam - stitiching where only the thread only penetrates halfway through the neoprene layer. This provides a strong connection without introducing holes through the suit.

3. Glued seams - often used in conjunction with the stitching techniques. Gluing the seams seals them completely from water flow. However, the glue can breakdown with time and usage.

4. Taped seams - A thin layer of neoprene taped insied the suit along the seams. This provides excellent restriction to water flow while also having a strong, durable finish.

5. Rubber seams - A liquid rubber seal is applied along the seams. Ths is often combined with inside taped seams and/or blind stitching and provides excellent water restriction, but does make the suit slightly less flexible.


Opening seals

Wetsuits will have openings at the wrist, ankles and neck (or around the face if it has a buit in hood). The more effective these seals are the less water will flush through the suit.

The effectiveness of these seals is governed by a few things:

1. Tightness - the tighter the better. Tighter seals means less water penetration.

2. Material - generally the seals are a rubberised neoprene, this sticks to the skin well and forms a good seal.

3. Length - longer seals will be more effective than short ones.


4. Size selection.

The final consideration is also one of the most important - finding the right size.

Wetsuits must be well fitting for them to work properly, seals will be best when tight, and loose fitting material allows water to move around in the suit.

Because of this there is a huge range of size and shape choice in wetsuits.

It is important to try a few on to figure out you size, and if in doubt, always get one slightly smaller than you think is needed to ensure the the fit is tight to restrict water movement. Wetsuits will also stretch with usage, so always better to go tight when in the shop.

Size chart for Neil Pryde wetsuits


Trying before you buy

It is strongly advised to try on a few different suits to figure out what size is right for you.

Inexperienced wetsuit users will often become uncomfortable in the warmest suits (e.g zipless, 6mm+, buit in hoods etc..) due to the movement restrictions that the suit causes. This makes buying online without trying on difficult, as if you are uncomfortable in the suit, you generally wont wear it, which completely removes any effectiveness of the suit!

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