Washable futon cover

[WalkerSisters]

We need to replace our futon mattress (not an Ikea one), used almost exclusively as a sofa in the office, partly as it's a bit old but mostly as it smells of cat wee (delightful). I want to get a new futon and then put a protector over it and a new cover. All the covers say 'dry-clean only' which if they really are would not be at all helpful. Anybody washed a futon company or any other cover?

Covers by The Futon Company can be machine washed at 40 degrees.
For example:
www.futoncompany.co.uk/covers/3-seater-futon-cover.html

If you click the specifications tab (about half way down the page) it will confirm details regarding fabric and washing, etc.