Wetsuit and underwear

Every time I’ve worn a wetsuit (mostly ww rafting) I’ve worn nothing underneath it. But I read somewhere recently that you can wear polypro layers underneath for extra insulation. Would this defeat the purpose of a wetsuit or at least make it less effective? I know that a wetsuit will trap a thin layer of water between your skin and the suit and your body will rapidly warm that water which, in turn, will help keep you warm. But a synthetic layer will hold even more water and draw more heat away from your body (initially) in order to warm that extra water. Or am I getting this wrong?

Try it yourself at home
With underwear, and without–in a tub full of cold water.

I’m sticking with “no underwear” myself. Wicking underwear would feel nice OUT of the water, because it would reduce sweat-induced clamminess a little. I’ve worn thin polypro liner gloves under neoprene gloves, and it is warmer than without the liners–for winter hiking.

But IN water, I doubt it. The closer the neoprene lies to the skin, the better, IMO. With a layer of “open cell” fabric between the neo and your skin, you are encouraging a higher rate of water exchange, which I would think means a constant influx of colder water.

But you really need to test this for yourself. Two of my wetsuits are too tight to allow wearing underlayers, anyway. And that keeps water OUT.

The difference in volume
of the water trapped in a tight weave synthetic fabric is minimal.

I’ve tried it both ways. I definitely stay warmer with an underlayer. I use a rash guard and a speedo. When it’s very cold I have a very thin neoprene insulating short made by O’Neil. It makes my 3/2 suit feel as warm as a 4/3.

Also warmer with underlayer
I wear rash guard/wicking layer under my wet suit and find it is warmer than without.


– Last Updated: Feb-25-08 4:52 AM EST –

My winter suit - Excel 6/5/4 - once I get it on, fits like a second skin with extra fat. When I have the opportunity to roll fast, I don't feel any water infiltration. If I get trashed a bit before rolling, I'll notice slightest of a trickle down the upper back before the water gets absorbed into wetsuit liner. I go bare back and bare ass under the wetsuit and am good for anywhere from 4-6 hours of surf paddling in under 40 degree water (air temps AND wind chill seem to have more impact than water temp). The weak point is my bootie/sock combo. I am using a 3mm sock under a 3 mm bootie combo. My feet can start to get cold in about 2-3 hours (I have come ashore after 4 hours and can hardly feel my feet). I Just got a 7 mm booties and will see how that goes.

I can fit rash guards under my 3/2 and 4/3 wetsuits and had tried it. I don't like wearing stuff underneath as I find it bunching in the wrong places after awhile. So, I go bare back and bare ass in these suits as well. I also noticed both these suits allow more flush through (as evident in feeling a trickle go from my neck down to my lower back before absorption). The higher the flushthrough, the less protection over longer period of time. I plan on replacing my Quicksilver 4/3 with a tighter fitting Excel suit this year.

An informal visual poll of the local, winter surfers indicate the overwhelming majority go at least bareback under their winter suits (I can't say when I last saw a rashguard, except on a few of the females). I don't know about bare ass since many modestly wrap a towel around their waist when getting off the rest of the suit.


I like
the polypro under my wet suit pants. If I have to go swimming and start moving my legs i will throw off a lot more heat so the difference with/without would be minor.

Ha Na Sing / Seadart … just walk up …
to the guys when they are (in the middle of) changing and ask them : ) … what do you wear ?

Come on man ( men ) its in the name of research.

Don’t Really Have Too…
if the other person has a good fitting wetsuit, you can tell what they have on underneath, or not…


better to look them in the eyes

Cheee heee hee, I know … you
are right. You can just tell the ‘real’ guys.


– Last Updated: Feb-25-08 1:55 PM EST –

They think I am a wuss anyway, tho' a tolerable one, for sitting on and using a paddle with a surf board rather than popping and standing up like real "surfers" do. For them, I at least wear a wetsuit and know a bit about surf etiquette, unlike the "silly kayakers" (that's actually me putting polite terms in their mouth) with the neon color nylon wear. ;)


The wetsuit, not the body.

Sing, have you found that some neoprenes stretch a bit after wearing them many times?

I have a shorty 2mm suit that has not stretched at all, a full 4/3mm suit that I have not used yet, and a full 3/2mm suit that was (I thought) tight when I tried it on but later became fairly easy to don and doff. That one does let water in if I stay in the water. To make it clear, I should have bought a smaller size in the first place, but initially it fit more tightly. They are all the same brand (Body Glove), though the types of neoprenes vary.

When I bought the 4/3mm suit, I got it in the same size as the shorty, and it was a major beehatch to put on or take off. But in my bathtub test, it kept all water sealed out. Not even a trickle.

Gives you a very thin abrasion layer between you and wetsuit and makes getting the wetsuit on a lot easier.

Another vote for underlayer
I find I stay warmer with a base layer under my Quicksilver 4/3. I get some water down the back and up the sleeves when rolling, but quickly is warmed and/or absorbed. I have not had any long term out of boat experiences with this set up, but has worked well for limited rescue practice, etc. Maybe not the best reason, but my suit also seems to be less stinky if I wear the underlayer.

Can’t Say They Have…
at least significantly. My 3/2 is BodyGlove and my first wetsuit. It’s stretchier anyway because of the thinner neo. Plus, being my first suit, I didn’t really appreciate what a difference a really snug fit makes (for me).

Lost almost 15 lbs in the past three months. Don’t know if the 3/2 and 4/3 will fit that well come spring. 3/2 doesn’t matter much since it’s warmer condition wear. The 4/3 I’ll replace.


Under layer
keeps the stink out.

it can help
to slow down the flow of water through gaps that develop between your skin and the suit as you move around. Decreased flow of water slows down the replacement of warm water with cold water.

It may or may not be significant to total heat loss.

Scuba with silk
I did a few years of commercial diving here in Florida and we would wear long johns under our wetsuits in winter. We were spending 2-3 hours under 55 degree water. Like others have said it helps fill the air gaps in between the suit and your skin. I used a thinsulate silk suit and the other diver used the cheap long underwear.

“Real Men Wear”…
I found a thin pair of Polypropylene or Polyester underwear made the wet suit more comfortable. I was told by several peiple this is fine to do, and will not diminish the effectiveness of the wet suit.

That being said, after winter paddling with a wet suit, 2 times, I decided this was not for me and washed it well with wet suit shampoo, dried it carefully and packed it away.

Anyone interested in a NRS Grizzly Hydroskin (2xl)worn only twice? I could use the cash. Paid $160.00 for it. Like new…

Stink hasn’t been a problem
I always wash the wetsuit after every paddle and turn it inside out to dry.