The eternal question... Neoprene or Trilam drysuit?

[stuartv]

Thank you for your suggestion. I noticed that in several posts you and others insisted that crushed/compressed neoprene is a much better option than plain not compressed neoprene. May I ask which is the advantage?

Like @RainPilot said - a normal neoprene suit - wetsuit or drysuit - compresses as you go deeper, causing your buoyancy to change. This not ideal. A crushed or compressed neoprene suit will behave very much like a trilam drysuit in that it does not compress as you go deeper. Your undergarments will compress, and that is one reason you add air via the suit inflator valve. Thus, your drysuit will stay fairly constant in its buoyancy.

That said, with a regular neoprene drysuit, you would still add air to the inside, so its loss of buoyancy is not as big a deal as the loss you experience with a thicker neoprene wetsuit. You can completely compensate for it with air inside the suit.

The other issue with the neoprene drysuit compression is that you might (only maybe) need a wing with a higher lift capacity. With the suit's compression, if you were to have a catastrophic loss of suit buoyancy (e.g. a big hole gets ripped open somewhere), you would have more negative buoyancy to compensate for.

 

[Gareth J]

Sbriguda

From your questions, it does sound like you haven't yet done a drysuit course.
If you can try both a trilam' and a crushed neoprene.

Trilaminate Drysuit.
Pro's - Buoyancy and thermal characteristic's don't change with depth,
in addition - light, quick drying, not bulky,
Con's - No thermal protection. Wrist and neck seals normally latex or silicon (tear easily and catastrophically.)
in addition - sometimes you look like your diving in a plastic bag.

Neoprene Drysuit
Pro's - Inherent thermal protection.
in addition can have neoprene wrist and neck seals. These are harder wearing and don't fail catastrophically.
Con's - thermal and buoyancy characteristics change with depth.
in addition - heavy slow drying, bulky

Crushed Neoprene Drysuit

Pro's - Buoyancy and thermal characteristic's don't change with depth. Some inherent thermal protection.​

in addition can have neoprene wrist and neck seals. These are harder wearing and don't fail catastrophically.

Con's - Slower drying. bulkier than Trilaminate. Expensive

Many view crushed neoprene as the best solution.

With dryglove options, latex (or silicon) wrist seals can now be changed by the diver quickly. Which means (if you have a spare) you are much less likely to lose a dive if you have a seal fail during kitting up. There are now solutions for silicon and latex neck seals, that allow a diver to change these themselves. In my view these are good, but you need to be careful changing the seal, so you are going to lose at least one dive on a trip (if you have a spare seal). These add cost to the suit!

Note some people are Latex intolerant, or they develop intolerance. The normally results in a 'hanged mans' appearance, a sore neck (and possibly wrists). Silicon is a better solution and doesn't irritate the skin, but you can't glue silicon (or its hard to do reliably).

​

 

[stuartv]

@Gareth J : You can now have a replaceable neoprene seal, even on a trilam.

Neoprene Neckseal

 

[Storker]

Trilaminate Drysuit.
Pro's - Buoyancy and thermal characteristic's don't change with depth,
in addition - light, quick drying, not bulky,
Con's - No thermal protection. Wrist and neck seals normally latex or silicon (tear easily and catastrophically.)
in addition - sometimes you look like your diving in a plastic bag.

Neoprene Drysuit
Pro's - Inherent thermal protection.
in addition can have neoprene wrist and neck seals. These are harder wearing and don't fail catastrophically.
Con's - thermal and buoyancy characteristics change with depth.
in addition - heavy slow drying, bulky

Crushed Neoprene Drysuit

Pro's - Buoyancy and thermal characteristic's don't change with depth. Some inherent thermal protection.​

in addition can have neoprene wrist and neck seals. These are harder wearing and don't fail catastrophically.

Con's - Slower drying. bulkier than Trilaminate. Expensive​

You forgot compressed neoprene, which is somewhere between conventional and crushed neoprene WRT changes in properties with depth.

I'd also like to mention that neoprene and compressed neoprene (don't know about crushed neoprene) can be fitted a little more snugly than a trilam suit, since there's some stretch in the material while a trilam suit has no stretch whatsoever. Think stretchy jeans versus old-fashioned Levi's. And a snugger fit makes for less air travel as the user changes trim.

 

[stuartv]

My Bare XCS2 drysuit was compressed neoprene and had some stretch.

I did not find it beneficial. Working against any constant tension is just that - work. If it's snug enough to be stretching, then it is too snug, in my book.

Further, I feel like the thicker material inevitably leads to bigger folds/wrinkles, which hold more air. My thinnest trilam (a Waterproof D9X) holds notably less air than my Bare did, I think. And I think it because as soon as I submerge, the water pressure squeezes all the air out - except for what is trapped in the wrinkles and folded areas. The telescopic torso certainly doesn't seem to hold any extra air. And the thinner material means the squeeze has it conforming to my body better than compressed neoprene does. So, overall, I believe both my trilam suits end up with less of an air bubble to manage than my compressed neoprene suit did. And, for the record, the compressed neoprene suit was, if anything just a hair too small for me. It was actually perfect in thin undergarments. With thick undergarments it became just a little too restrictive for me to reach my twinset valves without a struggle. So, the extra air in my compressed neoprene suit was NOT a side effect of it being too big for me.

 

[alvinsuper]

That depends on what you want to do.

Trilam to travel and for most kind of dives.

Neoprene/high density neoprene is for more affordable suits, they make a good fit and are convenient for those who like to dive with light undergarments (under certain circumstances). They have the buoyancy swings, slow to dry and heavy.

Vulcanized rubber on stretchy polyester for the hardcore stuff. Overall better than crushed neoprene. Super tough, dries quickly, easy to repair. And the suits are effectively seamless after vulcanization. Still heavy and incompressible and pricey.

 

[Sbiriguda]

Sbriguda
From your questions, it does sound like you haven't yet done a drysuit course.
If you can try both a trilam' and a crushed neoprene

Indeed and I would like to thank you all for your patience in answering. It is my habit to start collecting information quite some time before starting the courses and to get always several different opinions. Anyway I will take a drysuit course

 

[Storker]

My Bare XCS2 drysuit was compressed neoprene and had some stretch.

I did not find it beneficial. Working against any constant tension is just that - work. If it's snug enough to be stretching, then it is too snug, in my book.

My first drysuit was a Scubapro Everdry 4. Compressed neoprene. Fit like a wetsuit and was almost as easy to dive since I used only thin wool undergarments. It was stretchy enough that I didn't have to fight it even though it fit like it was painted on me. Virtually no air travel; I could easily stand vertical, feet up and head down without any issues. I'm just not doing that in my trilam suit.

I retired it and got a trilam because it didn't allow thick enough undergarments for winter diving, and the neoprene socks were so small that I couldn't wear anything but thin socks underneath. Wonderful summer suit, not particularly suited (pun not intended) for the three other seasons. I still dive it occasionally when the water gets up into the mid-teens C and the air is in the high teens/low 20s. Which doesn't happen too often around here, and only in July/August

 

[Sbiriguda]

Wonderful summer suit, not particularly suited (pun not intended) for the three other seasons. I still dive it occasionally when the water gets up into the mid-teens C and the air is in the high teens/low 20s. Which doesn't happen too often around here, and only in July/August

I can see from your signature you are from Norway. One day I would like to dive there. Just for my curiosity, apart from temperature, how is it visibility like? Does it vary depending from the season? Is it worth it to dive in full winter in Norway? Because here in northern Italy for example the idea is that the main issue is not cold but low visibility. In late spring, summer and autumn it's nice to dive in the sea. In winter it's better to dive in the lakes. The temperature is cold, especially up in the mountains and when you go out of the water, but the visibility is very nice. While in the sea the visibility becomes quite poor in winter

 

[Storker]

Just for my curiosity, apart from temperature, how is it visibility like? Does it vary depending from the season? Is it worth it to dive in full winter in Norway?

It all depends on where you are. As always Remember that Norway stretches from 58 to 71 degrees north, and the climate varies from similar to the UK or northern continental Europe to sub-arctic.

I live around 63 degrees and of course know those latitudes best. Generally, the coast has better vis than the fjords, and I think that's pretty universal. Here, count on 4-8m in the top layer (but during heavy spring algal blooms it can be less than 2m) and 6-12m below from early/mid-spring to mid-/late autumn. The surface layer can be from 5 to 20m deep. During the cold season, we can have very good vis, up to and above 20m all the way from the surface, so winter diving is definitely worth it. I'd avoid Dec/Jan, though, unless you're a night diver. The days are pretty short that time of the year, and even during the day the sun is pretty low on the horizon making even the daylight rather feeble.

If you want to try winter diving, bring a drysuit, preferably with dry gloves and a good hood, and thick undergarments. With the right gear, it isn't bad. Except when topside temps drop towards and below -10. When it gets that cold, you have to be pretty quick to get out of your suit and to break down your gear before your zipper and everything else freezes solid...