what exactly we are comparing

Down is the light, fluffy layer that waterfowl have beneath their outer feathers. Unlike a conventional feather, it has no rigid quill or shaft, but rather tiny filaments that spread out in different directions and create pockets where air is trapped. A feather, on the other hand, does have that central shaft, and tends to offer less loft and less insulating power relative to its weight than good-quality down.

That is why, when comparing natural fillings, it pays to look at their composition: the ratio of down to feather has a direct bearing on weight, loft, insulation and also on the price of the product.

Siliconised hollow fibre is a synthetic polyester fibre with small pockets of air inside it. Its siliconised finish reduces friction between the fibres, helping them slide over one another and keeping the filling even, soft and quick to recover its shape.

It is the material we use in our duvet inners, combined with a 100% polyester microfibre shell.

Both keep you warm with air, not with weight. The difference lies in how they trap it and how they behave afterwards.

Both materials work on the same physical principle: what insulates is still air, not the fibre itself. The difference lies in how much air each one holds per gram and, above all, in how they behave with use, moisture and washing.

down and fibre, head to head

Five criteria that make the difference in a product you use every night.

Warmth: down comes out ahead, with caveats

Gram for gram, down insulates better. The caveat is that what matters is not the grams but the temperature the bed reaches: if a 450 g fibre inner keeps the bedroom at the temperature you want, the slightly greater weight compared with its down equivalent is barely noticeable once you are asleep.

Price: a considerable gap

A good-quality down inner — one with a high percentage of real down rather than feather — costs several times more than an equivalent fibre inner. In the more affordable ranges, the product is usually a blend with a high proportion of feather: more weight, less warmth and the same washing demands. In that price bracket, fibre performs better.

washing: the difference you notice most

Of all the aspects to bear in mind, upkeep is one of those with the greatest bearing on daily use. Warmth is essential during the cold months, but how easy the duvet is to wash, dry and look after ends up being just as important in the long run.

Down cannot be washed at home. It needs professional cleaning or, at the very least, an industrial machine and a very long, controlled drying cycle: if the down stays damp inside, it clumps and permanently loses its ability to keep you warm. In practice that means an annual trip to the dry cleaner's, with all the cost and logistics that involves.

Siliconised hollow fibre goes in your washing machine, on a gentle programme at a moderate temperature. The silicone treatment is precisely what allows it to regain its loft as it dries rather than staying compacted. That changes your relationship with the product: you wash it when it needs washing, not when the calendar allows.

Gentle programme

Moderate temperature and a low spin. Check that the inner can move freely inside the drum.

Never fabric softener

It coats the fibre and clumps it, reducing its warmth. It is the most common mistake.

Shake as it dries

While it is drying, give it a shake now and then so the filling regains its original loft.

One practical note: with the 4 seasons inner, the two pieces are washed separately and each one is thinner, so they fit more easily into a domestic machine. It is an added advantage that rarely gets a mention.

allergies: why fibre has the easier job

It is worth being precise here, because there is a fair amount of confusion about it. The allergy is rarely to the down itself: usually it is to dust mites, which find a natural filling a more welcoming place to settle. On top of that, anyone sensitive to animal proteins may indeed react to the material.

Synthetic fibre resolves both issues: it is not an appealing environment for mites and it contains no animal protein, so it does not trigger allergies. Because it can also be washed at home at temperature, it allows for frequent washing, which is the single most effective way to keep allergens under control. That combination — a hypoallergenic material and straightforward upkeep — makes it the sensible choice in homes with children, pets or anyone with allergies.

why we work with fibre

With all the factors on the table, this is our choice and the reasoning behind it. It is made with the real-world use of duvet inners in a home in mind: years of service, frequent washing, children, pets and actual budgets.

Where down comes into its own

If your priority is the greatest possible warmth for the least possible weight — for instance, if any sensation of weight on the body bothers you — down does that job better than any fibre. And if there are no allergies in the household, the budget stretches to down with a high percentage, and an annual professional clean is no inconvenience, it is an option worth considering.

One word of warning is in order, though: when good-quality down is out of budget and the alternative is an entry-level range, the decision becomes simpler. Those blends with a high proportion of feather give less warmth than an equivalent fibre while keeping all the demands of a natural material. In that bracket, fibre is the more sensible option.