Trussed roofs?
Trussed roofs are made in a factory and are lifted onto the top of thr house. This is cheaper and a lot quicker way of building a roof. You can recognise this by looking up at your attic at the small square metal plates on your roof rafters and ceiling joists. There is no problem converting an attic with a trussed roof as long as you use structural steel beams (R.S.J.) reinforcement.