Hi all. Im currently in the middle of converting a single skin detached concrete garage. (6.7m long, 2.5m Wide 2m High) Ive got all the frame work and damp proofing up. Just waiting for the electrician to finish and ill be ready to install all the insulation and put up the drywall. Ive been reading everywere about ventilation. My current roof is black bitchumin corrugated, then a damp proof layer underneath, laying on the steel and timber frame. the highest point of the roof is about 2.5m and is about 2m at the loest point of the slope. Ill be putting 200mm space blanket loft insulation between the roof and 12.5mm soundboard which wil be used for the roof. The walls will be 50mm cellotex GA3000 and then 15mm soundboard. I have a single PVC window and door. Because it is a concrete block garage i cant jus remove a brick and put an air one in, so how would i get around provding adiquit ventilation. Ill be using the room everyday, opening the door, maybe even keeping it open in the summer, window open ect when im in. The main bit im worried about is the roof ventilation, the hot air trapped inside the roof and the cold outside will condense in the dampproof plastic and the drip back down onto the lights an ceiling board i would imagine. Ill be hopefully installing downlights and i hear they produce alot of heat but as my ceiling is going to be so low i cnt use normal hanging light points.