Browse Forums Heating, Cooling & Insulation Re: Ventilation in bedrooms with dual glazed windows 40Apr 08, 2018 2:30 am I have started this discussion so that other people retrofitting double glazing into their homes are aware of ventilation requirements. Summer - yes, you can open a window, unless it's too hot and you are running your split system which does not bring any fresh air. In winter its unlikely that you will sleep with an open window. In my test even if I ventilate before bed, 2 adults and a child will bring the CO2 levels above the recommended guidelines I don't know them all, the first 2 top of your list are best known. Rylock is a good company, Stegbar is for sale. 4 16345 Brass fly wire, you will need to cut it, shape it and jam it into brick slots 1 7562 |