Hello Annie and welcome to the forum.
I’m not sure about the first one as I can’t see the tail, it may be bombus terrestris, lucorum OR hortorum As for the one on the right….I think that tree bumblebees (bombus hypnorum) would be more likely to nest in the apex of the shed than a common carder bee. I could be wrong :D
Hopefully somebody with a LOT more knowledge than i have will come along and put us both straight….
Thanks, the shed had a fire years ago and as the inside was not suitable for painting we covered it in loft insulation then hardboard. Then lining paper and then painted it bright pastel colours. Maybe the colours attracted them or probably I’m guessing the fact that it was warm, sheltered and quiet.