I have just bought a 1970's house with no loft insulation or no ventilation. I need to address both.
How many 70mm soffit vents should I install approximately? 1 per 1m, 1.5m, 2m etc?
I know the best solution would be roof vents, but that is a bit beyond me. I want to install gable end vents, but Google is not revealing much. What is the best way to do this? Air brick in each skin or a large hole in both skins with a connecting pipe and a lourve vents (a bit like a shower extractor system)?