Help me understand wet suits for cold water

[lakehuronjoe]

I am just getting ready to get into the sport and I am acquiring gear, and I have some questions about wet suits.
I will be diving mostly Lake Huron, St Clair river, and quarries In and around Sarnia Ontario Canada.
I am 5' 8" and currently 180lbs this is a little heavy for me I generally run about 170lbs.
So my questions are about the styles of suits, what will work best for me, I see some refereed to as
"farmer Johns" curios as what the advantage is to this 2 piece design?
"semi dry suits" not sure what these are?
I also see that some wet suits have hoods and some do not?
What type or combination will hep me stay warm in the area I plan to dive?
I have found an as new 7mm wet suit at a decent price that seems to fit my size, but not sure if it is what i should be looking for?
any information or tips would be greatly appreciated.

thanks

 

[M-Cameron]

It really depends on your physiology and when you plan on diving.

A wet suit keeps you warm by trapping a layer of warmer water against your skin

A semi dry wetsuit does the same thing, except it has better seals to reduce how much water gets flushed through the suit as you dive

A dry suit keeps you dry inside, and keeps you warm by insulating you with air


For me personally, I dive a 7mm wetsuit in water temperatures down to 45degrees, and I’m perfectly comfortable......sone people can dive 7mm in even colder water..... and some people wouldn’t think about diving a 7mm in anything colder than 55 degree........it all depends on your personal body type

For the region you are in, if you want to dive all year round, a dry suit would be a good investment..... a lot of people in the Great Lakes dive those all year round......they are a bit more expensive however if you dive the Great Lakes you’re probably going to get one at some point.

But if all you plan to do is do a few dives during the summer, a 7mm is probably fine


The best thing to do would be to get recommendations from the dive ship you take your OW with and try out some different suits to see which you prefer

 

[rhwestfall]

Take the class in the shop rental gear, and learn in class before you buy...

Your likes and dislikes will drive your choices.

 

[CanadaDan]

The new wetsuits (I use Bare's Reactive line but there are other makers with similar tech) with reflective insulation are a good choice up here for casual divers. I dove a 5mm that basically gives the insulation of a standard 7mm frequently in water below 10c and have worn it below 5c but not for long or repetitive dives. I used a separate hood but only because I just haven't tried a suit with an integrated hood. The idea there is to eliminate another point of water infiltration. I didn't find I got a lot of water coming through the neckline when wearing a separate hood though. I also have a 3mm Reactive that is my travel full suit for liveaboards and cenotes when a tropical shorty just won't do for warmth. Wearing a thinner suit cuts down on the lead you have to wear but the reflective tech means you stay as warm with out the bulk.

Two piece farmer john styles allow easier donning of suits made with thicker materials. They also add more insulation to your torso by doubling up there. From what I've observed they seem to be less popular with more advanced suit makers. I imagine a lot of shops use them as rentals and training gear because of their flexibility in sizing and inexpensiveness.
FWIW I spend a lot of summer weekends at a dedicated dive area here in Manitoba and of the dozens of divers I see every weekend the only ones wearing farmer john styles are students.

Be wary of cheap wetsuits. Not all neoprene is created equal neither are makers. Spending an extra couple of hundred now beats replacing the entire suit.

I did make the jump to a drysuit given the water temps up here when I started diving more frequently. It's a pricey jump but well worth it if you plan to dive often locally. It's especially nice when doing repetitive dives in the summer when you want to take your suit off in the summer heat during surface intervals. A drysuit is far easier to get in and out of multiple times a day than a wet wetsuit. They dry faster as well. You can also tailor the insulation by varying the undergarments to tailor it to your physiology and water temps.

 

[lakehuronjoe]

Thanks for the responses, and the good info.
I plan to dive from the end of May till likely mid Sept, so during the fair weather

 

[Marie13]

A semi dry would be a good choice if you don’t want to go drysuit. I have a regular buddy who dives an AquaLung semi dry down to low 40sF on the Great Lakes and the quarries.

 

[lakehuronjoe]

Marie, what makes a semi-dry suit different than a wet suit?

 

[Marie13]

Marie, what makes a semi-dry suit different than a wet suit?

seals at wrists and cuff. Integrated hood with dam behind zipper to prevent as much water exchange as a regular wetsuit. New they’re around USD $500-600.

 

[icechip]

I primarily use a SEAC Masterdry semi-dry suit for New England waters and it works well. It has a separate hood that goes with it, although during the 'warmer' months I often opt for a neoprene beanie instead. My other semi-dry is a BARE and it has an attached hood and front chest zipper. I choose between the two depending on factors like month of year, wind conditions, number of dives, lengths of dives, etc. Have been comfortable diving down into the 40°F temps and have even dove with water temps in the 30°Fs (as long as the topside weather is cooperative such as sun, no wind, etc which helps when getting out)

 

[BlueTrin]

I have buddies who dive semi dry in fairly cold water.

If you know that you’ll need to dive fairly cold waters and do not want a drysuit you should definitely consider it.

I wouldn’t do it myself because I find my drysuit much more comfortable and warmer.

Please not that a semi dry is actually wet inside: just that you the water does not migrate as much due to the seals. But this means that you might be actually really cold during the interval/break/between dives.