What Wetsuit Thickness For What Water Temperature?

What Wetsuit Thickness For What Water Temperature? 14/03/2017

Whilst the UK may be blessed with a beautiful coastline stretching out over 11,073 miles, it is not blessed with the warmest climate. However, British people are largely undeterred from enjoying the great outdoors by something as trivial as the weather, but there are ways to make it a little less chilly!

You might assume the wetsuit is reserved for cool looking surfer types chilling on the Cornish coast, but it is a great idea for anyone who is looking to spend lengthy periods of time in cooler waters. Do you want to know more?


How does it work?

Wetsuits are made from neoprene, a type of synthetic rubber which can help to keep you warm in cool waters. 

An effective wetsuit is a tight fitting garment, with just enough space at the neck, wrists and ankles to allow a small amount of water to “fill” the suit. This thin layer of water is then trapped between the skin and suit and is warmed by natural body heat, thus keeping you warm. Fresh water is prevented from entering the garment as the suit is already full.

A wetsuit which is too baggy, may allow extra water into the suit and it won’t be effective. A good wetsuit should fit like a second skin.

Water Temperature Range (°C)

Wetsuit Thickness

Wetsuit Type

Seal Type



Rash vest


20°- 24°

0.5 mm - 2/1 mm

Top / Shorty


16°- 20°

2 mm - 3/2 mm

Spring suit / Full Suit


14°- 18°

3/2 mm - 4/3 mm

Full Suit + Boots


10°- 14°

4/3 mm - 5/4/3 mm

Full Suit (Boots + Gloves optional)

Sealed and Taped

6°- 10°

5/4 mm - 5/4/3 mm

Full Suit (Boots + Gloves optional)

Sealed and Taped

6° and below

6/5 mm - 6/5/4 mm

Full Suit (Boots + Gloves optional)

Sealed and Taped















What do I need to know about thickness?

There are many tables available which intend to explain what type of wetsuit you require for which conditions. However to a novice, it might be a little confusing. To help you understand things a little more clearly, we have explained what those series of numbers mean.

The thickness of suit required relates directly to the sea temperature. Bear in mind that the average sea temperatures for the UK ranges between 6-10 °C in winter and 15-20 °C in summer.

The measurement given in millimetres relates to the thickness of the neoprene. There are usually two or three numbers which are separated by a slash. The first number always relates to the thickness of the suit in the torso. This should be the highest number as the torso needs more protection to maintain the core heat of the body.

In the case that there are just two numbers present, the second number indicates the thickness in both the arms and legs. If there are three numbers present, the second number relates to the legs and the third to the arms.

It makes sense that the thicker the neoprene the warmer your body will feel. However thicker neoprene can be restrictive to movement and so thinner neoprene at the arms and legs allows greater flexibility.