How to choose a drysuit, essential dive gear for cold water

When diving in Canada and other temperate waters (or doing dives with extended bottom times in warmer climates) one of the most important pieces of equipment that you can buy is your exposure protection. In reality, this means a buying a drysuit and appropriate drysuit undergarments. But when divers begin thinking about purchasing their own gear they are confronted with a plethora of choice when it comes to this particular piece of exposure protection. At IDC we are more than happy to consult one on one with divers that have questions about what gear is most suitable for their diving needs, but I would like to clarify some of the different options available and their associated pros and cons.

There are a number of considerations to take into account when looking for a drysuit. Give yourself some time to evaluate what you want, need and what is most appropriate for your type of diving and environment. We could start at many places, but why don’t we look at the various types of materials that drysuits are constructed from and what this means to the diver wearing them to begin with?

Know the materials used in drysuits

There are a variety of materials and combinations of materials used in the construction of drysuits. Many of the original drysuits were made out of neoprene, often 7mm thick. These suits provide a great amount of warmth and buoyancy at the surface and are quite robust and fairly easy to repair and construct and relatively inexpensive. However, despite their warmth and positive buoyancy at the surface, these suits are compressible and therefore lose considerable warmth and buoyancy with depth as the bubbles in the neoprene compress under water pressure. At 33ft/10m, for instance they are 1/2 as warm and buoyant as they are at the surface. This can create major hurdles when it comes to weighting and thermal protection. These suits also tend to restrict mobility quite significantly, especially in the shallows, due to the thickness of the material. For these reasons they have largely fallen out of favour with recreational divers. Those divining the shallows for various commercial purposes may still swear by them due to their relative low cost and ease of repair.

There are compressed and crushed neoprene options available that offer the durability of neoprene and some amount of the warmth with minimal to virtually none of the problems of compression with depth as the bubbles within the rubber have been “pre-crushed” in factory. These suits, like DUI’s CF200 or Bare’s XCS2, are very robust, but remain quite heavy and somewhat cumbersome compared to their trilaminate cousins. Commercial divers may find that the fit and durability of these particular styles are the best for the work they do.

Matching the suit to your style of diving

Most modern recreational divers tend to opt for less cumbersome “shell”, “bag” or “laminate” drysuits. These can be constructed out of several materials and are usually found in bilaminate (two layers) or trilaminate (three layers) versions. These can be further broken down into the types of materials that compose these layers. There are several options available depending on what the diver is looking for in terms of durability, weight of the suit, mobility, et cetera. Several other factors and potential add-ons will effect these areas, as well, but we’ll get to those. An entry level, light weight, bilaminate drysuit may be composed of a polyurethane and nylon. Trilaminate suits may take these components and add another layer to them with another poly layer, or a butyl material or perhaps a blend with Cordura on the outside to add extra durability DUI’s skookum CLX 450 falls into this category, as does Santi’s Enduro. Many recreational divers will find these suits excessively heavy, but commercial divers or anyone subjecting their suits to abuse will appreciate the heavy-duty Cordura. A well-fitting, lightweight suit will give you the most mobility, alongside the new stretch drysuits available from several brands which are made in a variety of manners, including a stretchy outer layer and a bag-like inner layer or simply a single stretchy trilaminate material like Bare’s SB suit which uses a nylon/spandex blend, poly membrane and a nylon layer. The poly/butyl/poly trilaminates generally offer a convenient compromise between durability, weight and mobility. These suits include DUI’s popular new suit, the FLX Extreme and Bare’s Tech Dry. Santi Drysuit’s E.Space is similar but is composed of nylon, butyl and polyester.

The drysuit zipper has recently undergone some changes. Up until recently the metal zipper was the only real option, but now there’s the plastic “TiZip” on the market. Both are equally waterproof, but while the Tizip may not look as substantial as the old, familiar metal zipper it seems to be withstanding the abuses of donning, doffing, packing and travel better than its predecessor.

Compare the options on each drysuit

Many drysuits offer a plethora of options that the diver can choose from in order to build their own suit or to add to a suit. The drysuit foot pocket is often one of the biggest decisions to make once a diver has decided upon a suit. There are 3 basic concepts in foot design: First, is the full, rubber, attached boot. A diver need nothing but a good pair of socks for underneath this option. There is no extra equipment to remember and it tends to be a robust option. However, these boots tend to not fit a diver’s foot particularly well and allow for a fair bit of extra air moving around the foot pocket. Also, because they are quite stiff, they can impair ankle mobility and impeded several types of propulsion techniques (kicks). Second is the soft sock, usually made out of neoprene (sometimes compressed), with a separate boot worn over top. There are several different boots to fulfill this job, but in generally, this option feels more secure on the divers foot and due to lacing up or otherwise tightening the external boot, there is a reduction of air movement/expansion in the foot. Just be cautious not to over tighten and completely restrict air flow and maybe circulation, causing unnecessarily cold feet. This option provides a fairly stable platform for diver walking over slippery rocks or doing other kinds of shore entries. It unfortunately means another piece of equipment (well, technically two pieces) to remember to pack and make space for. Depending upon the external boot it also restricts mobility to some extent. Lastly, there is an option that sees a soft sock glued to a hard sole. It is sort of a hybrid between the two options. It offers the most flexibility as the ankle is entirely unencumbered and does not require any extra gear (unless one opts for the poorly named “fin grippers” to help reduce air expansion in the foot pockets). These soles come from some manufacturers with reinforcements made specifically with shore diving in mind. Not all suits out there come with options and some may only offer 2 of the 3 options listed above, but these are the general foot pocket considerations a diver may encounter.

Seals are another important option to consider in several drysuits. Some suits come standard with a particular type of seal and some offer options. Sometimes one can upgrade to some of these options. There are 3 general types of seal on the market for both the neck and wrists: neoprene, latex and most recently, silicone. All 3 types come with advantages and disadvantages. Neoprene seals, like neoprene suits, are probably the most durable over a long period and the easiest for a diver to make minor repairs to themselves. They tend to be a bit warmer (especially on the neck), but tend not to create as secure a seal. They also have to fit just right to create the seal. Latex seals fit a bit snugger against the skin and have more stretch than neoprene so that the same seal may fit multiple people. These seals have a limited lifespan and it tends to be a fair bit shorter than neoprene. While they usually create a better seal than neoprene, when they fail they tend to fail catastrophically. Without user replaceable seals this can mean the end of a day of diving or the end of a dive trip. This has long been the biggest complaint with latex seals. There are ways to deal with this; we will examine those soon. Lastly, silicone seals are the newest offering on the market. They tend to offer much greater stretch than neoprene or latex and a less prone to ripping due to a poorly placed fingernail than latex. They are thin and create good seals just as latex do. They do have to be replaced more frequently, however. Both latex and silicone seals are offered by several manufacturers in user replaceable options in both neck and wrist seals. This means that if you have a spare neck or wrist seal with you, a ripped seal does not mean the end of your diving and an extended dry spell while it gets repaired. This also means that divers can switch between drygloves (the best thing in staying comfortable since drysuits themselves came along) and wrist seals.

Additional options include extra reinforcement in areas of the suit that typically experience the most wear.

Weigh immediate choices with your long term diving plans

Ultimately, finding a drysuit that works for you is what will likely save you money in the long run. Chances are, opting for a suit because it seems like a good deal only to find down the road that it is far from your ideal suit will lead you to eventually buying the suit you should have bought to begin with. Some are lucky and the entry-priced suits are the ones that they truly want and need and suit them just fine. But give yourself time and weigh your options and determine what features you like in a suit and we can help you find them. Also, keep fit in mind. More than anything else, this will effect your experience in your suit. If a suit does not fit it will likely make you work harder and enjoy your diving less. It may even be a safety issue. Whether a suit is too big and hard to control, too small and restrictive in terms of mobility overall size is important. The finer details make a difference as well. We don’t all have the same proportions so just because you fit into a certain size according to a height/weight range on a size chart doesn’t mean that particular size will fit you well. Most charts have a number of measurements, including waist, hips and chest. These will help you determine your size much better than just height and weight ranges. If you don’t know these, we can help measure you up. If your measurements don’t align with a stock size suit, keep in mind that many companies offer custom cut drysuits. These are definitely a worthwhile investment for anyone not close to a stock size and even if you are not far off a stock size, may be something you consider just to truly have the perfect suit for you.