How to Dress in Layers Under a Ursuit Drysuit


Ursuit drysuits are designed to keep water out, while the correct underlayers manage insulation and moisture.

1. Base layer: moisture management

The base layer sits directly against the skin and its main purpose is to move moisture away from the body.

Choose:

• Synthetic technical underwear or merino wool

• Tight but comfortable fit

Avoid:

• Cotton (retains moisture and causes heat loss)

A good base layer keeps you dry from the inside, reducing chill during both high activity and rest.

2. Mid layer: thermal insulation

The mid-layer provides the primary thermal insulation by trapping air while allowing moisture to move away from the skin.

Choose your mid-layer based on conditions:

• Light fleece or thermal base layer for cool conditions

• Ursuit Thermofill Light for cold water or situations with low activity levels

• Ursuit Thermofill Heavy for extreme cold conditions, when water temperatures are near freezing and activity is minimal

Please note that layering must be balanced: excessive insulation can overfill the drysuit, reducing breathability and restricting mobility.

Thermal protection and EN ISO 15027 classification

Ursuit’s EN ISO 15027 approved drysuits are tested as a complete system, where the base and mid-layers directly affect the achieved thermal protection.

The suits are divided into two thermal classes based on the undergarment used:

• Class A (Highest thermal protection): Achieved by using the Ursuit Thermofill Heavy undergarment in combination with a drysuit equipped with integrated boots
  → Thermal protection time: 6 hours in +2 °C water

• Class D: Achieved with standard under clothing in all Ursuit drysuits
  → Thermal protection time: 2 hours in +10 °C water

In practice, the actual thermal protection always depends on the layering, environmental conditions, and the user's activity level.

3. Socks: keep feet warm and dry

Feet are particularly vulnerable to cold.

Best practice:

• Wear one or two pairs of thermal or wool socks

• Avoid tight socks that restrict circulation

• Match sock thickness to drysuit boot or sock size

4. Hands and neck considerations

While gloves and hoods are worn outside the drysuit, they affect overall thermal balance.

Tips:

• Choose gloves and hoods appropriate to water temperature

• Ensure seals sit comfortably against base layers without bunching

5. Fit and mobility check

After dressing, move through paddling, swimming, or working motions.

Check that:

• Layers do not restrict movement

• There is enough air space for insulation

• Seals sit flat and comfortably

6. Adjust for activity level

More movement = less insulation needed. Less movement = more insulation required.

Always dress slightly cooler when starting high-activity sessions to avoid excessive sweating.

A Ursuit drysuit keeps water out, but proper layering keeps you warm. By combining moisture-wicking base layers, effective insulation, and smart adjustment to conditions, you can safely and comfortably operate in cold and extreme environments.