The short answer is yes, but it needs to be a drysuit specifically made for scuba diving. You can find surface drysuits for kayaking and things to keep you warm and dry. The main problem with scuba diving is that the deeper we dive down the greater the pressure which crushes air spaces. So, the deeper you go, that suit is going to squeeze down on you and vacuum pack you in to your suit.
Drysuits for scuba diving will have a pair of valves fitted to compensate for this squeeze. One valve on your chest that connects to a hose just like your BCD so that you can add air into your drysuit as it squeezes. And a dump valve on your shoulder that allows expanding gas to escape as you ascend. You can also use your drysuit to control your buoyancy but, I wouldn’t wear a surface drysuit to go scuba diving it’ll be very uncomfortable.
Your drysuit is mostly there to keep water out and air inside. The air is the insulation, just like double glazing. But, wearing a drysuit alone means that the air is just going to hang out at the highest point, which is your back. So, divers wear an insulating undersuit and sometimes a base layer under that.
Your base layer is thin and is all about keeping your skin dry. Your undersuit is similar, they’re all designed to wick moisture away from your skin while maintaining a constant layer of air all over your body and allow gas to flow freely. When it gets really cold we do have electric warming undersuits to help keep us warm in the water.
The human body is a really awkward shape, especially when it’s moving around to keep you 100% dry. But, if you’re expecting to submerge yourself in water for up to an hour and stay completely dry, you may need to reassess your expectations. Even in a drysuit that fits perfectly and doesn’t leak, you’re still going to be in a sealed bag so, any perspiration isn’t going anywhere. That’s why we have our base layers.
As stated previously; your base layer and undersuit are designed to wick moisture away from your skin and a really good undersuit will make it so that you don’t even notice if you’ve had a small leak, they’ll still keep you warm when wet. To avoid leaks, make sure your drysuit fits properly, and look with your shoulders. Turning your neck is a great way for that seal to jump and let some water in.
They’re both great in their own ways. Wetsuits are far simpler. You throw it on at the beginning of the dive and jump in. You can move around as much as you like because water’s getting inside anyway and if they get ripped or punctured it’s not a big deal. However, they’re not as efficient. Water is a relatively poor insulator and the neoprene foam compresses at depth, reducing your insulation at the coldest part.
Drysuits are much more efficient at keeping you warm at any depth but, they do take some training and if something goes wrong it can ruin your dive. With an air space in your suit, your buoyancy can change and shift during a dive so, it’s important to have training before diving in a drysuit.
But, which is better?
A drysuit is better for most diving. But, when you don’t need it to keep you warm, they can be a bit of a hassle and it’s easier to just throw on a shorty
Eventually, however, you don’t get the same rush of cold down your back when you first jump in like a wetsuit. Although, a drysuit isn’t perfect and you will get cold eventually diving in cold water. It’s important that you think about this because being cold can affect your decompression and your dive computer might say that everything is fine to ascend when it actually isn’t.
If you’re wearing the correct amount of exposure protection for the water temperature you’re diving in, you shouldn’t ever feel cold unless something unexpected happens. It’s only ever your cheeks and what’s exposed to the water that ends up being cold. But, eventually, you will start to get cold (unless you’re in a heated submarine.)