Litter box sizes & insulation

For outdoor rabbits, whats the smallest size litter box you should have for two rabbits for their litter tray? At the moment I have a 32 ltr which is in their sleeping compartment, it takes up most the room but there is a gap at the side where one of the bunnies now has decided to wee, im wondering if I get a little bit smaller litter box so that it can go more in the middle of the sleeping compartment so theres not much room round the edge (no extra choice for weeing) then they will have to do it in the litter box.

Also they have lino all over the hutch in the winter do you put straw down over the rest of the hutch or just leave their hay/straw in the litter box? they will have a thermal cover by the winter to go over their hutch?:wave:

I would put newspaper in the gap where they go.

many people put a layer of newspaper then straw then hay in the winter.

Lino is not especially warm is it, so maybe so this on top of the lino for the winter. You could also add a snuggle safe and hand towels for extra warmth.

sue:wave:

thats a good idea, what about some fleece blankets would that be fine too?? you can get them at the cheap shop or tesco do a two pack (babies blankets) for not a bad price? will they not try to chew it though?