Wetsuit Thickness (2mm vs 5mm)

[Random Dude]

Hi all, hoping to get some advice from you guys as to what thickness of wetsuits should I go for.

I currently have a 3/2mm shorty wetsuit, but found it inadequate even when in the swimming pool, with me usually shivering after 40 minutes of diving.

Having established that I'm more susceptible to cold than most, I am now looking to purchase a full body wetsuit with a hood, in the hopes that it would help in conserving body heat.

Currently I have 2 wetsuits in my budget and size that are respectively 2mm and 5mm. Therefore, I am wondering whether it would be better to go with the 5mm given that at deeper depths, the 2mm would be compressed to almost nothing, thus compromising its insulating properties.

However, I am also worried that a full 5mm wetsuit might be overkill in tropical climates in most situations.

I am from Malaysia, and most, if not all of my diving would be in tropical climates such as in Malaysia, Thailand, Philippines, and Indonesia, with the average temperature around ±29 degrees Celsius.
Also, I am interested in tech diving, and should be taking my TDI AN/DP course in the near future. Would be nice if I could progress to greater depths without purchasing another wetsuit.

Hope to hear your recommendations and opinions on this!

 

[Steve_C]

Can you rent a suit and try it out. 3/2 to 2 does not sound that much warmer. Perhaps a 3 and wear a beanie. Or a 3 and a hooded vest?

 

[boulderjohn]

Swimming pools come in a variety of temperatures. I used to teach in one where we could do a 4 hour class in a 3mm shorty without a problem. I also taught in one where we wore 3mm full suits and had to take a break in the hot tub after 1.5 hours to get warm again. In that second pool I would have been cold pretty quickly in a 3/2 shorty, and I am more tolerant of cold than most people.

You don't see many 5mm suits in the waters you are diving. I think Steve_C has some good advice. I would want to be really sure I needed 5mm before making that purchase.

Wearing a hood makes a big difference.

 

[BoltSnap]

I find that 5mm suits are either too warm or too cold. I am now in either 3mm or in a 7mm and if I need a 7mm, I'd go for a semi-dry. If I am in a semi-dry, then I should be using a drysuit if I can afford it

Perhaps you should get a 3mm suit with a 1mm shortie option under this 3mm and a 7mm regular or semi-dry suit for colder temperatures.

 

[Neilwood]

If you are interested in tech diving, you might want to think about skipping straight to a drysuit although that might depend on what sort of tech diving you are wanting to do.

Deep - temps will probably drop off quite a bit at depth.
Extended duration - what seems like the right suit for a 40 min dive will probably not be for doing a 1-2hr dive (including deco).

 

[Tokenwiz]

I agree with Neilwood- consider a drysuit. It also acts a potential back up buoyancy device and can be easily adapted for different water temps by varying undergarment layers. If you decide on a wetsuit route I’d say if in doubt go thicker. If you are too warm you can always let more water in to cool down. You can’t make a thinner suit warmer once you are cold. The downside is adding more weight but if you get into a tech rig in warm water (or even cold depending on your body type) that likely won’t be your problem.

 

[SeaDreaming]

I can't speak to the drysuit stuff or to tech, but I get cold easily and dove in a 5mm suit in Cozumel last July (27-28ºC) and was perfectly comfortable in the water. The surface intervals were warm, but I would remove the suit from my arms and chest and would feel fine; my wet skin suit underneath cooled me off nicely. Just got back from Roatan (water temps 25-26ºC) and there were times I thought I'd start shivering.

 

[mi000ke]

This questions comes up often, and the conclusion generally is that no one can tell you what suit will fit your needs as everyone has a different tolerance to cold. I do almost all of my diving in water that is 26-30C, and I always wear a full 5mm wetsuit. I am never too warm, and this week with our water temps at 26c (79F) have been just slightly chilled by the end of my second dive. Meanwhile my daughter, who has little body fat, dove with me yesterday wearing just a 3mm short sleeve top over her bathing suit and was fine. Last year on a dive with water temps at 29 we had people on our boat diving in bathing suits, 3mm shorties, 5mm full (me), and one person in a drysuit!

But if it were me, I would invest in the 5mm not the 2mm.

 

[Dogbowl]

First, everyone is different and vastly so. I’ve seen people wear a swimsuit all the way to a full 7mm with hood diving in Cozumel. Personally, I wear a full 5mm, 3mm beanie and 6.5mm boots for a week of consecutive dives (10). Temps were around 26-28 degrees Celsius and I never got too warm. It was just perfect.

For us Canadians, we were advised to get a 5mm full suit and a drysuit (and forget about the 3mm). 5mm is for when we vacation in the Caribbean or Southeast Asia. If it got too warm, just pull the neck seal, flood the suit with sea water, and voila! you’ve cooled down. The drysuit is for all the other stuff...Canada, Florida springs, Galapagos, etc.

You also have to consider how many dives you will be doing consecutively and how long those dives are. If you’ll be doing 25 dives in a week on a liveaboard, you’ll need more warmth than if you’re only doing 10 dives. If you’re doing 3+hr. tech dives, you’ll probably want something beyond even a 5mm.

Also, age is a factor. Those of us who are getting older often report needing more neoprene. But I see you’re a young lad, so scratch that consideration!

 

[outofofficebrb]

Hi, @Melvin Moi Kai Sen. The queen of tropical water diving in a 5mm is here.

I have a 3mm, 5mm, and an 8/7 semidry. The 5mm is my workhorse. I am colder than most especially after back to back diving for multiple days - usually a minimum of 3-4 dives a day, 7 days at a time. Think Indonesian water....My workhorse is the 5mm. I wear this in tropical water from 26-30C and am still comfortable. It has definitely compressed from its original 5mm but I am hardly too warm and if I am it’s easy enough to flood but being cold on a dive is something I’m not interested in. Topside is another story but underwater, I find it really difficult to be too warm in a wetsuit.

We did a night dive in Komodo and it got down to 25 from being 26-30 all week. The 3mm folks were cold at depth and I was toasty. Also, in addition, I bring a hooded vest just in case but have only had to use it once.

I might be running a little more cold than you and all others but another option to consider is getting a full 3mm and getting a hooded vest. When it is colder you can wear both. When the water is warmer or you are not doing back to back diving over multiple days and the 3mm is enough just wear that. It gives you a lot of flexibility.