Cot/bed, junior bed - are they different sizes?

[Flibbertyjibbet]

Anyone know?
We are moving to a house with bigger bedroom for our 2 and 3yo boys who currently share a teeny room.
We were going to put them in single beds but realised this will take up a lot of space in the new bedroom (they are currently in a cotbed bed and a cot with a side taken off the room is so small).

I always assumed junior beds are the same size as cotbeds but my friend thinks I am wrong.

Is she right? Something bigger than a cot bed but smaller than a single would be great for them. Otherwise I think we will stick with cotbed size.

Please don't tell me to go straight to singles - its a 2 bedroomed house, we need extra space in their bedroom for all their toys and clothes that are currently all in our room!! and we don't plan to stay there long enough for them to need full single sized beds!!