Freediving Wetsuit – The ultimate buying guide

Cold and rainy or hot and sunny. No matter the conditions, a dive suit is always a wise choice to protect yourself from cold, sun burn, stingy marine life and scratches from rocks or reefs. But did you know that your choice can greatly affect your experience and improve your performance?

One piece, two piece, open cell, single lining, double lining, smooth skin, coated cell. There is a seemingly endless stream of new terms facing the first time buyer of a freediving wetsuit making it tricky to get it right.

Let’s start by breaking down your purchasing options into four basic categories.

1. Rash Guard or Lycra Suit

A rash guard or Lycra suit offer no thermal insulation and are only used in very warm waters as protection from sun, scratched and stingy marine life, such as jelly fish. If you’re not diving in the tropics or possibly summer time in the subtropics don’t bother.

Neoprene Wetsuits

Neoprene is technically a foam, consisting of bubbles of air or nitrogen trapped in a layer of industrial rubber. Not entirely different from a sponge, but more dense.

Wetsuits ultimately do not keep you warm, they just make the heat loss slower, giving you more time in the water before you get cold.

Most neoprene is made from petroleum while some Japanese manufacturers such as Yamamoto and Heiwa use lime stone as a raw material. Neoprene from lime stone is generally warmer, more durable, softer and is more water impermeable 95%  versus 60-70% for petroleum.
Limestone based neoprene is in some aspects more environmentally friendly than petroleum based. But no matter what, neoprene requires a lot of energy to produce and is not possible to recycle, so your discarded wetsuit will end up in a landfill somewhere. Make sure that you make a well grounded choice when you buy and take good care of your suit to maximize it’s lifespan and minimize your environmental impact.

2. One Piece Scuba or Surf Suit

Sure, why not? While not being optimized for freediving a one piece scuba or surf suits does offer basic protection against cold, sun and scratches.

The downside of these suits is that they require a zipper where there is always an opportunity for cold water to sneak in to steal your body heat. While duck diving you are also likely to feel cold water coming in through the collar as your shoulder blades press together during the arm stroke .

The neoprene used is also different. Scuba suits are made of different quality neoprene than freediving suits. As neoprene compresses its ability to keep you warm gets reduced, as does its buoyancy properties. Hence scuba suits are typically made of more dense neoprene (more material versus air bubbles) to resist compression better at depth. At the same time this denser material makes the suit less stretchy, restricting your movements as a freediver more than ideal.

Surf suits on the other hand are typically made of a more flexible neoprene to allow more comfortable and less restrictive movements required by a surfer. The flexibility of the suit is important for freedivers to assure freedom of movement and comfortable breathing on the surface. So from this perspective a surf suit is typically a better choice for a freediver than a scuba suit.

At the end of the day the fit is probably more important than anything. If it’s too small you can’t move comfortably, if it’s too big water will go in and out and cool you down much quicker. While scuba or surf suits are not ideal for freediving they can be a good place to start if you already own one.

3. Two Piece Freediving or Spearfishing Suit

This is by far the most popular design for freediving. The top piece is like a sweater with an integrated hood and a groin flap that connects in the front to keep the top in place. The bottom piece comes as either high wasted pants or farmer johns for added warmth over the torso.

This type of suit has many advantages for the freediver and they come with several sub categories. But let’s discuss them in general terms first.

Advantages of the two piece design:

1. The integrated hood stops water from entering through the collar.

2. No zipper is required which reduces the risk for leaks.

3. Allows for freedom of movement and breathing.

In warm waters the freediver may also chose to go with only the top to avoid over-heating, making them very flexible in usage.

Depending on the type of diving you are typically doing you are faced with a few further choices, starting with the lining or non-lining of the neoprene.

Neoprene is an amazingly flexible material and super efficient in slowing down heat loss, unfortunately it is not very resistant to sun exposure, abrasion or scratches. Therefor most wetsuits have an added lining of Lycra or other thin stretchy materials on one or two sides to increase the durability of the suit.

3.1 Double lining

Double lining suits has as the name indicates a lining on both the inside and outside of the suit.

This is the most durable form of suit. Apart from durability the other advantage of double lining is that it allows for easy donning, where the inner lining stops the neoprene from sticking to your skin.

The lined inner surface won’t seal as well as the naked neoprene allowing more water to move in and out of the suit and cool you down quicker. The lining material is less stretchy than neoprene making the suit less stretchy than a single lining or no lining suit. Though, manufacturers are continuously coming up with more and more stretchy lining materials making this disadvantage less and less important.

3.2 Single lining

The single lining may be on either the inside or the outside of the suit depending on what properties of the suit are being prioritized. The single lining in itself makes the suit more durable by minimizing the risk of over stretching the neoprene beyond its breaking point and ending up with a tear

Single lining outside (Open cell inside)
Usually referred to as open cell suits as the non-lined inner side is exposing the cells of the open neoprene cells. This is by far the most popular design for recreational freedivers and spearfishermen. Some manufacturers may offer various inner coating options such as Titanium Coating, Gold Coating or whatever they may call it. What it is is a thin coating of the neoprene to make it easier to don.

The open cell inside has the best thermal properties as the naked neoprene sticks to your skin and thereby minimizing water transport inside the suit. The lining outside makes the suit more durable and resistant to wear and tear from rocks, reefs, shores, boats and whatever challenges the suit needs to overcome. The single lining makes the suit more flexible than a double lined suit. It is the best compromise between warmth, durability and flexibility.

The open cell neoprene sticks to your skin making donning very difficult. Soapy water as a lubricant or rich amounts of baby powder are required to don the suit on dry land. An alternative if the water is warm enough is to don the suit in the water. The most environmentally friendly donning method. The open cell is prone to cuts from nails during the donning process so care is needed.

3.3 Single lining inside (Smooth skin outside)

This type of suit is often referred to as smooth skin, though that term only refers to the outer material of the suit. The smooth skin is a treatment of the neoprene where the open cells are smoothed over and closed, leaving a smooth and very hydrodynamic surface of the naked neoprene.

This is by far the most popular type of suit for competitive freedivers due to its hydrodynamic properties. The smooth skin can increase the speed of freefall up to 30% versus a lined suit. The inner lining makes the suit more durable compared to suits with no lining at all and more flexible than suits with double lining. The inner lining makes it easier to don compared to open cell suits allowing fairly easy donning even on dry land. The smooth skin can easily be treaded in manufacturing to achieve a wide range of colours and effects.

The smoothskin is very sensitive and susceptible to cuts and scratches from nails and wear and tear. UV light also affects the smooth skin more than a lined suit causing the material to crack after prolonged exposure to

the sun. Only consider a smooth skin suit if performance is your top priority.

3.4 No lining (Smooth skin open cell suit)

A smooth skin open cell suit has no lining at all. Open cells on the inside and smoothskin on the outside for maximum performance.

Maximum thermal and hydrodynamic properties combines the best of two world in one suit.

Very, very fragile. The open cell interior requires soapy water or rich amounts of baby powder to don. A neoprene suit without any lining holding it back is very easy to over stretch and tear apart in the donning process. Always keep a tube of neoprene cement handy for repairs. Unless you are a sponsored competitive freediver do not consider this type of suit, at least not in less than 5mm thickness. 5mm thick neoprene for colder waters gives a reasonable resistance to tears but for 3mm or less, make sure someone else is paying for your suits.

3.5 Sandwich

The sandwich is a relatively new and so far not so common concept where a layer of Lycra or nylon is sandwiched between a thin layer of open cell neoprene on the inside and smoothskin neoprene on the outside, making it invisible for the eye.

More durable and resistant to over stretch than no lining. Maintains the thermal properties and hydrodynamics of open cell/smooth skin suits.

Less stretchy than open cell/smooth skin suits. Still very sensitive to scratches and wear & tear.

4. One Piece Freediving Wetsuit

The one piece freediving wet suit is similar in design to a traditional scuba wetsuit, but with a different neoprene and slightly different cut to allow flexibility of movement and maximum seal in the neck.

The one piece freediving suit is typically thin, 1 – 2mm with an inner lining and smooth skin on the outside. This is a performance wet suit favoured by many pool divers who need a suit with minimal buoyance, primarily to increase their hydrodynamics and less so for warmth. They have also gained an increased popularity for depth diving after being favoured by Constant Weight No Fins World Champion William Trubridge.

High hydrodynamic properties with minimum buoyance due to its thin neoprene, absence of hood and single layer neoprene (Two piece freediving suits have double layers of neoprene from the groin up to the end of the high waist pants or the whole torso in case of farmer johns).

Requires zipper. Risk of water entering through the neck. Less thermal insulation due to its thin neoprene and lack of hood.

Once you have decided on the type of suit that’s best suited for you, you have to make a few more choices.

Other Considerations

As all neoprene compress under pressure your suit will go through changes in bouyancy with changing depths. The deeper you dive, the less buoyance you will have from your suit. This is a complicating factor that becomes more noticeable the thicker suit you’re using.

For example, diving with a 5mm suit and dive weights setting your neutral buoyance to 10m, you will experience a noticeably more negative buoyance at 20m compared with a 3mm suit set to the same neutral buoyance at 10m. This will make your ascent more challenging in the thicker suit. You will also notice more resistance in the first few meters of your descent making that more challenging as well in the thicker suit. This will of course be even more accentuated with a 7mm suit made for really cold waters. Basically, the thicker the suit you are using, the more aware you will be of it. So the basic approach should be to go with the thinnest suit you can while stillensuring that you stay warm enough.

Personally I dive in a 3mm to 3.5mm two piece open cell suit with high wasted pants in anything from 22 to 30 degrees Celcius. I will be cool but not cold in the lower range and warm but not over heated in the upper temperature range. This makes it a very versatile suit for most of my needs. When the water temperatures drops towards 20 degrees and down to 16-17 I have a 5mm open cell suit to keep me warm. So far I haven’t been diving in colder waters than that. But I know people who dive in northern Norway in 4°C water in 7mm Open Cell suits and keep warm enough for more than an hour of diving.

Standard size or Custom made?

If you consider yourself to be of quite average proportions you may opt for a standard sized off the rack suit. Different manufacturers use different sizing standards and cuts, so ideally try on the suit you consider before buying. Unfortunately Open Cell suits are difficult to try on and most retailers won’t let you do so due to the need to get wet or powdered up. So at least take your own measurements according to the manufacturer’s instructions and study the sizing tables carefully. In case you are in between two sizes, generally go with the smaller. Ideally consult your retailer for guidance.

Today custom made wetsuits can be ordered at very reasonable costs from companies such as Elios in Italy or Dive In in Croatia to name two. If you want the best fit or you if know that you are somewhat outside of standard proportions you may want to give custom made a serious thought. With a custom made suit you can get your perfect suit with a choice of neoprene quality, colour, desig and an option of reinforced knees or elbows, knife pocket, loading pad for spear guns or whatever requirements you may have. A custom made wetsuit from Elios typically costs 200 – 400 EUR.

Solid Colour or Camouflage

Many Spearfishermen tend to favor camouflage wetsuits. The idea is that you should blend in with the environment and not spook the fish. Based on this idea manufacturers have come up with various camouflage patterns and colours for any thinkable diving environment.

If you’re asking me it’s more of an esthetic preference as most spearfishing techniques requires you to trigger the curiosity of the fish making camouflage obsolete. Some top spearfishermen use camouflage and some don’t. There don’t seem to be any distinguishable difference in their success.

Making your choice can be a challenge. Don’t hesitate to contact me or leave a comment if you have any questions.