Average loft conversion size?

[Goingslowlymad123]

Appreciate this is a 'how long is a piece of string question', but any rough sizes would be great. Thank you.

Two thirds the size of the floor it's going on top of. At a guess.

floor below which was not altered 429 sq ft, loft conversion floor (double bedroom and shower room/loo) 250sq.

Mine is 27sqm. It is an L-shaped dormer conversion to a 2 bed terraced house.

Thanks. We're trying to decide whether to stretch ourselves and do the loft, which will turn it into a 5 bed from 3. Don't think it's going to be worth it and will just do 4th bed on first floor.