Why Upgrade to a 4mm Wetsuit for Winter Sailing?

Winter sailing can be some of the most rewarding time on the water — crisp mornings, steady breezes, quieter waters. But with colder conditions comes one big challenge: staying warm. Your wetsuit is your first line of defence, and choosing the right thickness is critical. Here’s why upgrading to a Supertherm 4mm wetsuit can transform your cold-weather sailing experience.

Quick Look:

1. How Neoprene Keeps You Warm

Neoprene works by trapping a thin layer of water between your body and the suit. Your body heats this water, creating an insulating barrier. The thicker the neoprene, the more insulation it provides — making it much harder for heat to escape.

2. Why Thickness Matters

• 1.5mm neoprene (like our Thermaflex) offers flexibility and comfort for mild to warm conditions.
• 4mm neoprene (like the Supertherm) adds serious insulation for cold-weather training, helping you retain heat for longer sessions.

Think of it like the difference between a light jacket and a winter coat — both have their place, but when the cold bites, you’ll want the thicker layer.

3. Advanced Linings for Extra Warmth

The Supertherm 4mm range isn’t just thicker — it’s smarter. Enhanced linings wick moisture away from your skin, add thermal comfort, and dry faster between sessions. That means less of the “chill factor” when you put your wetsuit back on for the afternoon race.

4. The Role of Stitching: Flatlock vs GBS

Not all seams are created equal.

• Flatlock stitching (used in thinner suits like Thermaflex) is breathable but allows small amounts of water through — fine for warmer sailing.
• GBS (Glued and Blind Stitched) seams, used in all our Supertherm range, are sealed to minimise water entry. This keeps the insulating layer of water more stable and your body much warmer.

5. Designed for Winter Performance

Sailors often assume thicker neoprene means restricted movement — not with Supertherm. Our panels are engineered for stretch and flexibility where you need it most, so you stay agile and comfortable while still benefiting from maximum warmth.

6. Pairing with Other Layers

The Supertherm range is built to be part of your complete winter system. Layer it up with:

·       Thermal base layers like our Polypro or Hot tops & leggings — not only do they help manage moisture, but they also add an extra insulating layer, trapping air and boosting warmth.

·       Spray protection such as the Aquafleece® or SB1 Inshore Dry Smock — your outer defence against wind and water.

Together, these layers create a system that locks in heat, keeps you dry, and stands up to whatever winter sailing throws at you. Read more about layering by visiting our Layering Guide.

Don’t let the cold hold you back. With the right wetsuit, winter sailing can be just as enjoyable — if not more — than the summer season. Our Supertherm 4mm range is designed to give you the warmth, comfort, and performance you need to sail on through the colder months.