HI EVERYONE. WE'VE JUST RECEIVED OUR PLANS FROM OUR ARCHITECT FOR A LOFT CONVERSION AND ARE AWAITING PLANNING PERMISSION - THERE'S A FRONT DORMER INVOLVED. THE PLANS SHOW THAT THE ORIGINAL PURLINS ARE TO BE REMOVED AND BE REPLACED WITH STEELS FURTHER DOWN THE ROOF AND ONE RUNNING ALONG BELOW THE ORIGINAL RIDGE. THE STEELS SPAN BETWEEN THE OUTSIDE WALLS AND TWO INNER WALLS AND REST ON THESE. COULD SOMEONE TELL ME HOW THESE SUPPORT THE ROOF ABOVE? ARE THEY PUSHED IN UNTIL THEY REST AGAINST THE RAFTERS OR ARE THEY CONNECTED TO THE RAFTERS IN SOME WAY?