King size duvet too small for cover? What's going on?

[pigsinmud]

This is starting to annoy me. We've had our current king size duvet for about 5 years I should think. Over the past year I've noticed that it seems too small for the covers. I bought a new cover, thinking that perhaps it was something to do with them being so old (not sure what I thought had happened to them!), and I have the same problem. There is about 10cm of spare cover on the sides. Lengthways it fits fine.

I am most perplexed by it. It is a cheap hollow fibre duvet. Could it be that it's original bounciness was giving it it's size and now that has flattened out it doesn't fit...iyswim! I would have thought that would have applied to the length as well as the width though.

Are you sure you have it the right way around? Is it wider than it is long? Ours often seems to have shrunk but its just because the cleaner has put it into the duvet cover the wrong way around so it just needs turning and it then fits.

Just turned it round. It now fits ok widthways, but not lengthways.

Being cheap and hollow is probably why. Our cheap IKEA ones have done this. The decent John lewis ones have not.

Double duvets are square so a king size should be wider than long.
Also where is your duvet cover from? Ikea duvet covers tend to be a bit longer, I think due to continental sizing

One duvet cover is Homebase (classy) and the other is Dunelm Mill - not sure about the third, but I can tell you they were all cheap! I chucked the double duvet on the bed, before I turned the duvet round, and the king size was wider than the double.

I've got one cover which is too long. I shake the duvet to the top end and tuck the loose bit into the bottom end of the mattress. It also helps to stop the whole thing shifting off the bed in the night.

I am also very frustrated, so much that I bought another duvet, thinking that when it was washed it must have shrunk, but no difference! I can’t decide whether to buy another duvet but get a super king or have all my covers taken in by about 20 cm ....