The purpose of a wetsuit is to trap a thin layer of water between your body and the suit. The water is warmed by your body heat which then in turn keeps you warm, a bit like a hot water bottle. In contrast, Dry Suits (often mistakenly referred to as wetsuits) keep you warm by keeping you bone dry and hopefully preventing a single drop of water from coming into contact with your body (hence the name).
Wetsuits are made of a special type of rubber called neoprene and come in many different styles and thicknesses. The first step in deciding which type of wetsuit you need is to simply look out of the window! Wetsuits are designed for either warm or cold seasons (or somewhere in between) and wearing the wrong type of wetsuit at the wrong time of year will leave you either too warm or too cold.
If you've never worn a wetsuit before you may be surprised how difficult they are to get on and off. This is normal, but a bit of practice makes perfect most of the time.
As with most things, it is easy to get bamboozled with technicalities, but here are the main things a novice needs to know about wetsuits.
A shorty wetsuit is one with short sleeves and short legs (the legs cut just above the knee). This type of wetsuit offers the maximum amount of flexibility but is intended for warm weather as water can usually enter a shorty wetsuit quite freely.
A full wetsuit is exactly that - one with long arms and legs. A full suit provides the most warmth but is the most restrictive in terms of movement. However, in cold weather this will be a tradeoff that you will be more than happy with. Some thinner full suits allow water in quite freely, others do not. Most water enters a wetsuit either through the stitching, the neck and arm seals, or the zip. Suits designed to restrict water penetration will therefore have more attention given to these 3 areas.
The short arm wetsuit has full legs but short arms and make the perfect cooler weather wetsuit for tow sports (waterskiing, wakeboarding etc) as the short arm design minimises forearm cramps often associated with long arm designs.
These are great for really cold days as you can literally wear warm fleecy layers underneath. Very cosy, but better suited to watersports that require less physical movement such as kayaking.
Wetsuit thickness is measured in millimeters and is usually expressed as two measurements e.g. 3/2mm or 4/3mm. The first number tells you how thick the suit is around the body area and the second number indicates how thick the suit is in the arms and legs. Thinner material is used in the arms and legs as it increases flexibility. Thickness is a good measure of how warm the suit will feel so basically the higher the number, the warmer the wetsuit. Therefore, the colder the weather the thicker the wetsuit you need and vice versa.
"Flatlock" stitching is perfect for summer suits as it allows water to flow into the suit quite freely. "Glued and blindstitched" construction is great for colder weather as it only allows a small amount of water in. "Glued, blindstitched and Taped" construction is ideal for really cold weather as it allows little or no water in.
All you need to do now is decide which suit you need and how much you want to spend, and after that it's all down to which colours you like the best.