We expanded, but unfortunately, the builders made a mistake and placed the roof trusses at the same height as those in the existing house where the panel ceiling is nailed directly to the trusses. Since we didn't want a lower ceiling height (already at 230), we solved it by placing boards between the trusses before applying plastic so we can nail the panel directly to them. My question is about the bathroom: do we need to lower the ceiling and have gaps there, as it says everywhere that one should have an air gap. But I have a hard time seeing the function. There's no air circulation in the air gap anyway, right? We will also have proper mechanical ventilation, so I doubt the air gap makes a difference, but does anyone have other experiences?
