I am still in pondering mode about my loft insulation.
After a bit of looking around I see that knauf do a type of insulation that looks pretty neat. Its called space blanket
However I have 2 questions.
1) My joist height is 4 inches (100 mm), but their product only sells in 150mm and 200mm. If I installed the 150mm and later boarded on top of it, (effectively making 150mm into 100mm), would that simply mean that the insulation would act as if it were 100mm, or would it be less effective as there wouldn't be as much air to trap the cold.2) The space _between_ my joists varies ever so slightly, it appears to be around 400mm. All of the loft insulation that I have seen sells in 370mm width (they must assume 400mm joist centres). Has anyone else seen this before and got any advice on what to do?
Thanks
Dean