Customer Services

Customer Services

PRIMALOFT®

 

Lightweight insulation that stays warm — even when conditions turn wet.

PrimaLoft® is a high-performance synthetic insulation used in selected AKU winter and cold-condition models. It’s designed to deliver warmth with low bulk — lightweight, compressible and breathable — with excellent water repellency to support more consistent comfort in cold, damp weather.

The human body uses energy to keep warm. PrimaLoft® uses a patented structure with ultra-fine microfibres to help the body retain heat and conserve energy — particularly valuable when winter conditions are changeable.

  • Warmth without bulk: efficient thermal performance for cold days.
  • Moisture-resistant: maintains insulation performance more reliably than down when damp.
  • Comfort in motion: breathable structure helps reduce the “overheated then chilled” cycle.
What this means for you

More consistent warmth and comfort in cold, damp conditions — with less weight and less “sweaty” build-up than heavily insulated designs.
High-performance synthetic insulation used on selected AKU cold-condition models.
What is PrimaLoft®?
 

PrimaLoft® is a premium synthetic insulation designed for protection from the cold. It’s often described as as warm as down, while being lightweight, compressible and breathable. Because it’s synthetic and water-repellent by design, it remains a dependable choice for damp, changeable winter weather.
How it works (and when you’ll feel the difference)
 
Warmth by trapping still air

Insulation works by holding a layer of warm air near your foot. PrimaLoft® microfibres create lots of tiny air pockets that slow heat loss — helping you stay warmer in low temperatures, wind, and long periods of low activity.

Worth knowing

Fit affects warmth. If boots are too tight, you reduce circulation and compress insulation — often making feet colder. A little toe room is normal in winter footwear, especially with thicker socks.
Why it’s useful in damp winter weather
  • Water repellency: supports warmth retention even when conditions are wet or humid.
  • Breathable comfort: helps manage moisture during movement, reducing “hot then cold” swings.
  • Low bulk: warmth without excessive weight — useful for active winter walking and long wear.
Best use cases

Cold conditions, winter hiking, low-temperature work environments, and anyone who tends to get cold feet in wet UK winters. Many PrimaLoft® models pair insulation with a waterproof lining (e.g. GORE-TEX) for full wet-weather comfort.
Watch: PrimaLoft® in action
 
What you’ll learn in 60 seconds
  • How insulation traps warmth: loft creates air pockets that slow heat loss.
  • Why synthetic helps in wet weather: warmth stays more consistent when conditions are damp.
  • How to get the benefit: fit + socks + drying are the biggest comfort multipliers.

A short visual explanation of how PrimaLoft® insulation supports warmth without adding unnecessary bulk — and why it’s so useful in damp winter conditions.

Tip: Insulation works best when it isn’t compressed — aim for secure heel hold with comfortable toe room, especially with winter socks.
Jargon buster (plain English)
 
Insulation
A layer that traps warm air near the body to slow heat loss.
Synthetic
Man-made fibres (not down). Typically more moisture-resistant and easier to care for.
Loft
The “fluff” of insulation. More loft usually means more trapped air (more warmth) — unless it’s compressed by a tight fit.
Wetting out
When the outer fabric saturates with water. Waterproofing depends on lining/construction; insulation helps comfort in cold, damp conditions.
Find PrimaLoft® insulated models
 

PrimaLoft® insulation appears on selected models built for colder conditions and winter use. Browse by category below.

Outdoor
Hunting
Tactical
Professional

Tip: if you tell us your typical temperature range and activity level (active walking vs standing around), we can point you to the right level of insulation.
Care (keep warmth and comfort consistent)
 

Insulated footwear performs best when it’s kept clean, dried correctly, and not overheated. Poor drying is one of the fastest ways to reduce comfort over time.

1
Dry gently (no direct heat)
Remove insoles and dry naturally away from radiators/fires. Direct heat can damage materials and reduce long-term comfort.
2
Keep the upper clean
Brush off mud and grit. Built-up dirt reduces breathability and can make feet feel clammy, even in winter footwear.
3
Choose the right sock
Use a technical winter walking sock that moves moisture away from skin. Cotton holds moisture and can feel cold.
Quick warmth check

If your feet are cold in insulated boots, the usual causes are: fit too tight, socks too thin for conditions, or standing still for long periods in very low temperatures. Tell us your model and use case and we’ll help.
PrimaLoft® FAQs
 
Is PrimaLoft® waterproof?
PrimaLoft® is insulation, not a waterproofing layer. Waterproofing comes from the boot/shoe lining and construction (for example, a waterproof membrane). PrimaLoft® helps you stay warm and comfortable, including in damp conditions.
How warm is a PrimaLoft® boot?
Warmth depends on the amount of insulation, the overall lining package (often paired with a waterproof membrane), your activity level, sock choice and fit. If you tell us the model and how you use it (moving fast vs standing around), we can guide you to the right warmth level.
Will insulated boots make my feet sweat?
They can if the insulation level is higher than you need for your activity or temperature range. For high-output walking, a lighter build can feel more comfortable. Moisture-wicking socks and correct drying also make a big difference.
Why are my feet still cold in insulated boots?
The most common reason is fit that’s too tight — it reduces circulation and compresses insulation (loft). Other common causes: damp socks, standing still for long periods in very low temperatures, or using socks that don’t move moisture well.
Does PrimaLoft® lose loft over time?
All insulation can compress with use. Correct drying, avoiding prolonged direct heat, and not storing boots tightly crushed helps maintain comfort over time. If your boots feel less warm than before, we can help you troubleshoot fit, socks and drying first.
Can I use orthotics with PrimaLoft® boots?
Usually yes, but volume matters. Very thick orthotics can reduce toe room and compress the insulation effect. If you share your model and orthotic thickness/type, we’ll advise the best approach.
Can I wash PrimaLoft® insulated footwear?
We don’t recommend machine washing. Clean with lukewarm water and a soft brush/cloth, then dry naturally away from direct heat. Remove insoles to speed drying.
Is PrimaLoft® down?
No — PrimaLoft® is synthetic insulation. A key benefit is that it maintains warmth more reliably in damp conditions compared to down.