First test: Fjällräven Keb Loft Jacket (2014)

When the thermometer goes negative, down insulation is what most of us turn to. But down loses some of its insulating performance when wet, making it less than ideal for the UK; and it’s pricy.

Recently, outdoor brands have tried to make synthetic insulation as efficient as down, and the latest attempt comes from Fjällräven. G-Loft Supreme is a synthetic fibre that promises to feel like down while offering exceptionally high insulating ability even when wet. It was developed in Austria, and Fjällräven has exclusive use of it until 2024. The unique blend of hollow and super-thin polyester fibres has a natural ‘cluster’-forming ability, similar to that achieved by high-quality down. It is this that allows G-Loft Supreme to create lots of small pockets of air to provide higher levels of insulation than other synthetics. Thanks to the use of 10 per cent recycled material, the fibres also have a good ‘memory’ capacity that allows them to be compressed and then spring back to their fluffy form, say when a jacket is unpacked from a rucksack. Like all synthetic insulation, G-Loft Supreme is also quick-drying and easy to wash, two areas where down is far more challenging to care for.

In the UK G-Loft Supreme is used in the Keb Loft Jacket, inside a polyester inner and outer with Fjällräven’s G-1000 reinforcement around the hem, pocket openings and under the main stormflap for greater durability in these areas. There is a front zip, and that stormflap has press studs to keep it in place. There are two zipped pockets that are large enough for OS maps, although these aren’t high enough to access easily if wearing a rucksack. The cuffs are elasticated and have no adjustment. On the inside are two mesh stretch stash pockets. Our sample weighed 405g (size men’s L), but Fjällräven says the production version will weigh 436g due to having slightly more insulation inside.

The Fjällräven Keb Loft is not the most well-insulated jacket I have worn, making it less useful for really cold conditions than some down jackets. But it does offer a good medium level of insulation for general outdoor use, such as when camping at valley level. I’d want something warmer for sitting around in the snow, but the insulation is ideal for something you’d carry in your pack most days throughout winter in the Lakes and throw it on to take the chill off a summit brew.

I prefer all insulated jackets to have a hood, because if it’s cold enough for extra insulation in winter then it’s cold enough for a proper hood – so it’s disappointing that this model does not have one.

At £195 the Fjällräven Keb Loft Jacket is right at the top of the price range for this type of garment, but it’s a good weight due to the highly efficient G-Loft Supreme insulation.

Outer polyester, G1000 reinforcement
Insulation G-Loft Supreme synthetic
Weight (size men’s L) 436g
Sizes XS-XXL (men’s): XXS-XL (women’s)

G-Loft Supreme is a great new insulation, but I’d like to see it featured in a jacket with a hood to make it really useful for colder, breezier UK conditions. If you don’t want a hood the Fjällräven Keb Loft Jacket is a great lightweight product and it compares well with numerous other synthetic insulation jackets.

Review by Graham Thompson
First published in Trail magazine December 2014