The soft, fine, fluffy feathers that are either the first covering of a baby bird or the insulating layer of an adult bird.
Down is the magic ingredient in fillings. The softest and most comfortable pillows are made of pure down. Grannies eiderdowns that were as light as a feather and kept you as warm as toast – without central heating, or perhaps just one fire in the whole house, were made of pure down.
The point of down is that it traps air in between its tiny fibres; this air is insulating and if puffs up, but is easily squashed, so whilst it’s perfect for an eiderdown, when a quick shake will revive it, it’s less enjoyable with weight above it. A top pillow is fine when there is a firmer one beneath – again, a quick shake and it’s back. For chair seats and backs it needs to be mixed with a more substantial feather, one that will hold the weight as well as air. The small duck feathers are still best – those without quills and lots of small hairs. These mix with down to create beautifully soft, more substantial and less expense fillings. These are fine for sofas seats, but they do collapse and need to be plumped up quite often. They also look either untidy, or comfortable, depending on your viewpoint.
The least expensive and most affordable option is curled poultry feather which is perfectly good for day to day use, when the proportions of down to feather, ands the amount of filling are right. For chair and sofa backs, scatter cushions and soft seating, an 85% down to 15% feather is a good mix; for seats a 50 / 50 mix works well. There is still a good amount to daily plumping up to do, but the seats will be comfortable and they will wrap themselves around you somewhat.
The most offered option is 85% feather / 15% down, which is heavy and cumbersome- there is not much of the down element to it, but as long as the pads aren’t over-filled, then there is still room for air and the seats retain some shape.
When we make comforters we use bought down duvets, the best we can afford for the project, to gain something of the feel of a proper eiderdown. We also use duvets to make padded loose covers and quilted curtains – just for the lightness, and the fact that the ready made channels are quite good at holding the filling where it should be – or we’ve added more.