3mm vs 5mm?

[thomasj1107]

So I was pretty set on getting a 3mm full suit as I only plan to buy one suit right now. It will be for diving mostly the keys, FL east coast, and Florida gulf coast. I’ll occasionally hit a spring or two. I recently had a 3mm in 63 degree quarry and got cold towards the end but I usually run pretty hot so it wasn’t bad. Dive shop nearby recommended a 5mm and said I can always open it up and let water in and cool down, but if I have a 3 and get cold, can’t warm up. Anyone else think the 5 is the better option if trying to only get one? Thanks!

 

[tbone1004]

I prefer 3mm+hooded vest to a 5mm. If it's cold enough to need a 5mm it's cold enough for a hood, and if you're in a wetsuit with a hood then a hooded vest gets you the extra thickness on your core and reduces water movement around your head/neck as well as most of the water entry from the back zip.

 

[thomasj1107]

I prefer 3mm+hooded vest to a 5mm. If it's cold enough to need a 5mm it's cold enough for a hood, and if you're in a wetsuit with a hood then a hooded vest gets you the extra thickness on your core and reduces water movement around your head/neck as well as most of the water entry from the back zip.

At what temp is this the way you do it?

 

[tbone1004]

At what temp is this the way you do it?

cold tolerances are highly personal. I was born and raised in Massachusetts and grew up swimming in the cold waters of Maine and Cape Cod. I am still very much a polar bear at heart and I can comfortably dive in a bathing suit in the 70f springs for well over an hour and in a 3mm up to 2hrs and 3mm+hooded vest up to about 3. As far as going colder it is all a function of how much total exposure you have per dive, how many dives per day and what happens between those dives *very different experience in summer vs winter* and how many repetitive days of diving you have. I have taken 3mm+hooded vest down to 40f for about 45mins without issue but again, I'm a polar bear and it was a very good hooded vest. All that to say it is very difficult to make solid recommendations on exposure protection without knowing the full story.

 

[Boarderguy]

At what temp is this the way you do it?

Exposure suit vs temp is very subjective. I was recently in Hawaii diving at/below 100' in just board shorts and a rash guard. There were others in the same area with full length 3mm and 5mm suits that stayed in 50-60' range... in the Puget Sound I dive a 7mm farmer john but am looking at going with a 7mm jumpsuit. I'll be getting the new suit and will drive it a few times to determine if a vest is also needed.

 

[Alpha2K4]

I was in Key Largo in Feb the water temp was 75 and I was wearing boardshorts and a rash guard. I also was in a 2mm Shorty and it was 80degrees last week.

If you think you'll be cold get a 5, better to have more than less. I personally wouldnt do more than a 3mm but like everyone else said before, all depends on how cold you get.

 

[BoltSnap]

I can always open it up and let water in and cool down

This is BS, not true at all.

I own two suits, 3mm and 5mm and use each for different temps. I own a 2mm shortie, front zip, that can go over the 3mm just in case the 3mm isn't warm enough. A hood would help too as @tbone1004 mentioned.

 

[BoltSnap]

I was born and raised in Massachusetts and grew up swimming in the cold waters of Maine and Cape Cod.

You did?????? I lived and dove there for a very long time. I went to engineering school there too. I consider Boston/Worcester my "home town" in the US. Never heard of you

 

[johndiver999]

Your premise is faulty. You can NOT buy one suit to handle the temperature extremes that the various seasons and the geographic variations will impose.

 

[tbone1004]

You did?????? I lived and dove there for a very long time. I went to engineering school there too. I consider Boston/Worcester my "home town" in the US. Never heard of you

Indeed, Clinton MA is home. Lived in Maine for a few years after college. Depending on when you left I was probably still a kid