I'm working my way through my dormer bungalow which was built without a shred of insulation in the 1960s. My biggest problem is the area of sloping roof/ceiling on either side of the dormer windows, i.e. from the (small and cramped) loft space down to the eaves above the ground floor. The property was re-roofed about 10-15 years ago (nobody thought to fit insulation!) So I have a number of "slots" to fill, each about 4 x 20 x 72 inches, and not sure the best method to use. I could try pushing celotex into the slots though it would have to be cut small to ensure I could push it all the way down. I thought of pouring chunky polystyrene loose-fill down the slots - it couldn't escape at the bottom and would still allow some air circulation - would this be sensible or not? Any ideas would be welcome.