Hi my house has an old large lean to conservatory/orangery 10.5mt long by 3.2mt deep, which needs work. It has a single skin dwarf wall in good condition, as is the tiled floor. Wooden frame single glazed windows and doors which have rotted. 60mm X 140mm hard wood rafters at 780mm spacing supporting a sloping 25mm polycarbonate roof and glazing bars. I recently had the roof panels off because they had slipped, the all went back ok and are in good condition and leak free.
Ideally I want to replace the polycarbonate roof with a solid flat roof and replace all the windows and doors with uPVC. My concern is will the single skin dwarf wall and uPVC frames support the weight of a flat roof? Will I require building control? Who should I approach, a window company or general builder to get the work done?
Thanks in advance.