Cold water & wet suit

[broncobowsher]

Insulation does no good if you leave the window open.

Coldest wetsuit dive I ever did was when someone assisted me zipping up the wetsuit and folded the back of my hood. Left a finger sized rat hole that let cold water down my back. Little things like that can completely kill the warmth of a wetsuit. I replaced the standard hood with a hooded bib to prevent future issues. (then replaced all that with a drysuit)

With good waterflow management I could do southern California dives down into the low 50s with just a 5mm. That was the first gen Henderson Aqualock. Silicone seals between parts of the suit.

Your results will vary. I've seen the same dive done in a shorty and I will only do it in a drysuit now.

 

[JuLe]

I do cold (4C = 40F) dives with a 7mm wetsuit (cressi fast) with 6mm boots and 5mm gloves and hood. I wear a thin thermal underwear set underneath. Before I go in to the water, I pour (or as my buddy to pour) warm water from a thermos into the suit. This way there is warm water inside the suit and I don't have to feel the shock of cold water trickling in and wait for my body heat to warm it up.

30-60 minute dives go without any problems. I feel reasonably warm and comfy.

The worst part is coming out of the water, taking gear off and getting dry. That's when it starts to feel cold. Drying off fast and having warm clothing and hot tea ready helps.

 

[34109411]

I do cold (4C = 40F) dives with a 7mm wetsuit (cressi fast) with 6mm boots and 5mm gloves and hood. I wear a thin thermal underwear set underneath. Before I go in to the water, I pour (or as my buddy to pour) warm water from a thermos into the suit. This way there is warm water inside the suit and I don't have to feel the shock of cold water trickling in and wait for my body heat to warm it up.

30-60 minute dives go without any problems. I feel reasonably warm and comfy.

The worst part is coming out of the water, taking gear off and getting dry. That's when it starts to feel cold. Drying off fast and having warm clothing and hot tea ready helps.

really? i have a bares velocity 7 mm coldest i dove is 15 celcius ( all the rest is also 7 mm or more).

i need to try diving in april coldest is 4 and warmest 10.

 

[34109411]

really? i have a bares velocity 7 mm coldest i dove is 15 celcius ( all the rest is also 7 mm or more).

i need to try diving in april coldest is 4 and warmest 10.

i am afraid to go dive under 15 c i thought i be going down.

 

[broncobowsher]

If the fit isn't right, if the water flow isn't controlled, it doesn't matter if it is 2" thick neoprene, you will be cold.

Insulated walls only work of the doors are closed and the drafts are controlled.

You really have to pay attention to how a wetsuit works. Your warm body, about a pint (half liter) of warm water between you and the suit, the suit that is the actual insulation, the cold water. The insulation of the suit itself if pretty basic. That pint of warm water is the magic, Your body can warm that little bit of water. But if you have a poor fitting suit and it holds a gallon, you can't heat a gallon of water and still be comfortable. That is where a proper fitting suit matters.
If that pint of warm water is flowing out and new cold water is flowing in. Again, you can heat A pint of water with your body heat. You can't heat pint after pint in a continuous flow.

Keep that in mind and you can stay fairly warm in cold water. A suit that fits someone may or may not be the right fit for you. You have to try them on. A little baggy in places may be fine in a warm water 3mm suit, but that isn't going to work in cold water. The colder the water, the more "right" the suit has to be. Close enough turns into not close enough.

All while not being too tight to restrict range of motion or circulation/blood flow.

There are a few places that still make made to measure wetsuits if the off the shelf models don't fit right.
Back in the day, you could mix and match upper and lower 2-piece suits for a better match. Double layer over the core added insulation, but often at added water turnover from all the extra joints.

 

[rjack321]

really? i have a bares velocity 7 mm coldest i dove is 15 celcius ( all the rest is also 7 mm or more).

i need to try diving in april coldest is 4 and warmest 10.

@JuLe is from Finland, they have different blood than the rest of Homo sapiens. I could never do 4C for 60mins in a wetsuit either

 

[JuLe]

really? i have a bares velocity 7 mm coldest i dove is 15 celcius ( all the rest is also 7 mm or more).

i need to try diving in april coldest is 4 and warmest 10.

Yes. I will also say that it is not for everyone, but for me it worked so that I have enjoyed the dives.
But I must admit that I have recently purchased a drysuit and will start diving with it this coming season. (when the ice clears)
Last year I got tired watching my daughters getting out of their drysuits all warm and comfy after a dive and me trying to get dry in 8C temperature on a windy day after spending time in 4C water. The girls made sure I heard about how nice their drysuits felt EVERY DARN TIME we came up.

 

[34109411]

sure
many new divers (including myself) were told that a wet suit keeps you warm by trapping water inside the suit between the neoprene and your body.
your own body heat then warms that water and thats what keeps you warm.
this is of course nonsense.
everyone knows that anytime your skin gets wet, your body looses heat. water is NOT an insulator. even warm water is NOT an insulator.
why else would they have developed the "dry suit", and dry gloves etc.
the neoprene is the insulator. and in a perfect world, if we could keep 100% of the water out, then that is as efficient as the suit can possibly be.
so ask yourself which wet suit would be warmest?.......
1 - a 7mm thick suit that does not fit quite right, has poor arm and leg water dams or some type of seal system, a separate hood with no neck seal system at all, and does not have glued and blind stitched seams
or
2 - that same 7mm thick suit that fits your body like a second skin, has some type of arm and leg water dams or seals (like my old Bare velocity did), an attached hood, and has fully glued and blind stitched seams
remember, if the suit lets water in, it will also let that water out.
so when you are diving, swimming, and moving around etc in the water, the water that is in the suit that is supposed to keep you warm, ends up getting pushed out and replaced with cold water. this what i call "flushing".
now does this make a huge difference when diving a 3mm wet suit in 84F water? maybe not, but it is certainly a far bigger problem when diving in 40F water.

 

[rjack321]

This is the scuba version of homeopathy. The "layer of water keeps you warmer" is totally wrong even if it's repeated over and over with increasingly technical terms.

Water has no insulating properties whatsoever and a wetsuit would be warmer still if that layer of water didn't exist. Such a suit does exist and it's called an uncrushed neoprene drysuit. For wetsuits, the use of neoprene with a slick skin side and as tightly fitting as possible are all ways to decrease that supposedly 'insulating' (/s) layer of water and increase the warmth factor to the extent you can with a given thickness of neoprene - the less water between you and the suit the better.

 

[CD24]

Where are you reading that water "has no insulating properties whatsoever?" Water can absorb and retain heat and I can't find anything to the contrary online.