The following requirements will need to satisfied for the loft conversion:
A three-storey building should have fire precautionary measures in place such as: - a) Fire doors within the rout of fire escape (corridors) protecting bedrooms. b) Interconnected smoke detectors on mains electric. c) Fire protection to ceiling of the first floor. d) Fire protection to the underside of the staircase. e) Adequate floor joists. f). Discharge from top floor to an area close to exit door. g) Insulation and ventilation to the ceilings of the top floor and roof cheeks if any. h) Thickness of insulation should be around 150 mm of solid insulation to underside of the roof. I) Staircase must comply with maximum pitch, handrails regulation, risers, goings and balustrades.
If the room is not used as a bedroom the ventilation and insulation regulation should still apply.