5mm Wetsuit vs layering 3mm wetsuit with a vest/neoprene shorts etc...

[Belzelbub]

What temperature are you comfortable in with your 3 mm, how many dives/day do you do.

Exposure protection and tolerance to cold are individual. I have a home in SE FL and dive a 3, 5, and 7 mm full suit +/- a 5/3 hooded vest every year to cover usual water temps of high 60s to low/mid 80s for 2-4 dives per day.

Yep 100%. I would absolutely be fine with a 3mm and a vest, or shorty for year-round diving where I live. But, I've been told that I'm not exactly normal in cold tolerance. It's not uncommon for me to see other divers wearing double (or more) the wetsuit thickness than I would need.

So, if you tend to get cold, the full 5mm would probably be the better choice. If you tend to be warmer, then the layering would probably be sufficient.

 

[jadairiii]

@UWDawgDiver I always wear my hooded vest under the full wetsuit, otherwise the water between the suit and the vest flushes too easily and a lot of the thermal benefit is wasted.

Most, if not all, flushing comes from the neck seal on any suit, by wearing the hooded vest on the outside, it completely covers the neck seal, thus virtually eliminating flushing effect.

You will especially realize this if you start scootering.

 

[Centrals]

Avoid buying cheap wet suit as the material gets compressed in no time at all.

The Wetsuit Guide: Types of Wetsuit Neoprene

There are many different types of neoprene out there and they play a large role in the overall performance of a wetsuit. The best neoprene is insulating, lightweight, stretchy, durable, and hydrophobic (making it absorb less water).

www.cleanlinesurf.com

I prefer layering because it offers flexibility. There is no wet suit for all season even in so called warm water in SE Asia for me.

 

[UWDawgDiver]

A lot of opinions here, mostly contradicting each other. I too am getting ready to upgrade my wetsuit which I have been diving in since 1992 (but only 150 dives). I don't know the thickness, but maybe it's between a 2 and 3mm. I am normally a cold person. I keep our house temp at 74F. But that wetsuit keeps me surprisingly warm. We just dove on the big island of Hawaii and I added a 2.5mm hooded vest (under) and 2-3mm shorts. That worked pretty well for me when most around me were wearing 7mm suits. Both the vest and the suit fit really tight and I am thinking part of the reason they keep me warm is because there is not a lot of room for water to flush through. We are getting ready to dive Bonaire and I am thinking of adding a 3mm shorty on top (3 layers). We'll see how that goes.

 

[El Diablo]

A lot of opinions here, mostly contradicting each other. I too am getting ready to upgrade my wetsuit which I have been diving in since 1992 (but only 150 dives). I don't know the thickness, but maybe it's between a 2 and 3mm. I am normally a cold person. I keep our house temp at 74F. But that wetsuit keeps me surprisingly warm. We just dove on the big island of Hawaii and I added a 2.5mm hooded vest (under) and 2-3mm shorts. That worked pretty well for me when most around me were wearing 7mm suits. Both the vest and the suit fit really tight and I am thinking part of the reason they keep me warm is because there is not a lot of room for water to flush through. We are getting ready to dive Bonaire and I am thinking of adding a 3mm shorty on top (3 layers). We'll see how that goes.

You are right on many things.

You do need a new wetsuit if it is 20 years old. By now although it can look relatively in good condition, his property of returning to its normal thickness after being compressed has diminished considerably. In simple words, it has lost plastic elasticity. The micro bubbles on the neoprene will not regain their original size anymore.

You are also right on the tight fit restricting water circulation. Careful not to wear anything too tight that might restrict blood circulation and make you uncomfortable and colder.

As I commented previously, layering in diving isn't the same as layering in hiking. You will restrict mobility the more layers you add.

Closing, there's a couple crucial factors that we need to take in consideration,

1. Where are you diving and what temperature is the water
2. How many dives per day as you will get colder after each dive
3. Own body composition, someone with more stored fat will be warmer than someone fit as fat acts as an insulator.

Dive safe and have fun.

 

[kyle191]

I did the Red Sea for two weeks in April-May, I dived a full 7 mm and was quite comfortable, could probably dived my 5 mm with my 5/3 mm hooded vest.

I dived the Red Sea in early March 2020. I used my old school full length Lava Core suit and a Farmer John 3mm over that and was fine. I only needed 6lbs of lead in that set up. I was comfortable. Plus I wore a hood to cover my noggin.

This comes up a lot in the bow hunting world where you have to stay warm on a tree stand motionless for 8-10 hours at a time. Many guys choose layering. Some like the single heavy suit. But ALL the guys know that to stay warm, you have to cover your head. 70% of the heat escapes there. Get a quality hood and wear it. THAT will keep you warmer than extra mm's of neoprene.

Best of luck to you

 

[kyle191]

This topic comes up quite a bit on the bow hunting forums I belong too. If you really want to learn about being cold...try bow hunting in a tree stand in early December in the mid west.

I have found the key to staying warm and comfortable in and above the water is your head!!! Most of the heat escaping your body comes out of your noggin. Keep your head warm, your body will stay warm too. That applies above and below the water.

I layer and very rarely get cold enough where I don't want to do another dive. I did a Red Sea live aboard in early March with an old school full body Lava Core (1.5 mm equal), a 3mm neoprene shorty, and an old school Lava Core sweat type shirt. The key???? I had a proper fitted neoprene hood keeping my melon warm.

I like the layering because it is flexible and I find it easier to get in and out of multiple thin layers than a single bulky 5mm or 7 mm suit.

KEEP THAT NOGGIN WARM!!!

 

[scubadada]

I have a 3, 5, and 7 mm full suit and a 3/5 mm hooded vest. I can comfortably dive anything from the low 50s to the mid 80s. In SE Florida I sometimes take a couple of full suits in the car and wait until I hear what the recent temps have been. We occasionally have very cold upwellings that decrease the water temperature significantly. I always take the hooded vest with me to deal with the water temperature. Flexibility is the key.

 

[johndiver999]

This topic comes up quite a bit on the bow hunting forums I belong too. If you really want to learn about being cold...try bow hunting in a tree stand in early December in the mid west.

I have found the key to staying warm and comfortable in and above the water is your head!!! Most of the heat escaping your body comes out of your noggin. Keep your head warm, your body will stay warm too. That applies above and below the water.

I layer and very rarely get cold enough where I don't want to do another dive. I did a Red Sea live aboard in early March with an old school full body Lava Core (1.5 mm equal), a 3mm neoprene shorty, and an old school Lava Core sweat type shirt. The key???? I had a proper fitted neoprene hood keeping my melon warm.

I like the layering because it is flexible and I find it easier to get in and out of multiple thin layers than a single bulky 5mm or 7 mm suit.

KEEP THAT NOGGIN WARM!!!

Many people hate hoods and end up wearing say a 5 mm suit and no hood. I have even seen people wearing a dry suit in relatively cold water with no hood.

I personally wear some sort of hood nearly all the time, even if it is lycra and only beneficial for sun protection and sting protection.

I agree completely about the thermal benefits of a hood. Another significant benefit is that you can get away with a thinner suit and a warm hood and thus minimize the total amount of neoprene the diver needs and thus reduce the amount of lead and also reduce the amount of buoyancy swing.