Sleeping Bag Insulation Explained

Sleeping Bag Insulation Explained

Vango have invested greatly in research and development, including new and innovative equipment, in order to provide the best insulation for sleeping bags.

Synthetic Insulation Sleeping Bag Fills

Synthetic insulation uses a mix of fibres to trap warm air from the user in the sleeping bag. These insulating fibres are thermally bonded to a backing fabric, which is then attached to the shell of the bag. The key advantages of synthetic insulation are price, durability and the ability to still provide insulation should it get damp. The types of synthetic insulation we use in our sleeping bags are detailed below;


Single-hole siliconised hollow fibre

Try saying that 10 times in a row! Single-hole is our most common bag fill at Vango, and can be found on most of our synthetic family and adventure sleeping bags. A reliable and versatile fill that increases the sleeping bags durability, and maximises lofting potential for extra warmth. The hollow fibre retains loft in damp conditions, ideal when condensation may be a factor.

Best Use – Campsite, Sleepovers, Scout Halls, Caravans

Found on – Nitestar, Wilderness, Vango Family Sleeping Bags

 Vango nitestar sleeping bag

Insulite® Superfine

The Insulite® Superfine insulation fill has excellent compression properties, allowing the sleeping bag to be packed down into a compact stuff sack. Extremely durable and lightweight, the Insulite® Superfine provides an ideal fill type for youth groups who will be wild country camping such as DofE and Scouts, and also for lightweight hiking enthusiasts. Insulite® fill offers a great warmth to weight ratio at a compact size and price. Superfine indeed.

Best Use – Expedition, Wild country, Campsite

Found on – Ultralite

 Vango ultralite sleeping bag

Insulite® Helix

A unique development for 2016, the Insulite® Helix fill combines a mixture of hollow and multi-channel fibres. The Insulite® Helix channels moisture away through tiny fibres. Much in the same way paint is drawn up into a paint brush, the fibres draw moisture away from the body against the force of gravity, fancy stuff. Heat in, moisture out.

Best Use – Wild Country, Campsite

Found on - Latitude


Down Bag & Mixed Insulation Sleeping Bag Fills

Down feathers are the soft underlay found on duck and geese. Down has a different structure to normal feathers. The many tiny strands pack down to a fraction of the lofted size, allowing a high volume of air to be trapped inside the bag. Vango only uses ethically sourced down.

Down is measured by fill power. Imagine one ounce of down in a cylinder. Add a weight on top. An ounce of down that retains 700 cubic inches is deemed to have a fill power of 700, an excellent standard of down. The higher the fill power the better the potential warmth-to-weight ratios.

Down quality is also expressed by ratio of down/feathers a 90/10 is a very high quality fill, composed of 90% down and 10% feathers.

In recent years, developments have led to the introduction of water-resistant down insulation. Hydro-Barrier down helps down to retain insulative properties when wet.


Down is the highest performing insulation, providing a greater warmth to weight ratio and smaller packsize than synthetic. Down is a premium component and requires greater care than a synthetic bag. Down sleeping bags should be stored in a large storage sack and only compressed when necessary. Compressing down for extended periods can affect its ability to loft. Using a waterproof stuff sack is a good way to keep your down bag dry when it is in your rucksack. If down gets damp, its ability to loft, and therefore provide insulation will be compromised.

Best Use – Expedition, Wild Country

Found on – Venom

 vango sleeping bag Venom

Insulite® Fusion

Hybrid filling: 70% 90/10 700FP Hydro-Barrier down, 30% 4T synthetic insulation. 4T Insulation is an innovative synthetic insulation fibre. It improves the warmth to weight ratio by trapping air in its patented channel structure. The interlinked lattice supports the down and achieves superior loft, even in damp conditions.

vango fuse sleeping bag technology

Insulite® Fusion is our new bag insulation for 2016. A hybrid of down and our 4T synthetic insulation.

Best Use – Expedition, Wild Country

Found on – Fuse 

vango fuse sleeping bag