I would like to nail insulation horizontally across the sloping roof joists in the loft together with a vapour barrier. There will be a free space between the joists and under the insulation for outside air to circulate.This is instead of placing insulation on the loft floor as this is used for storage. In this way, can I insulate right down to the loft floor thus blocking outside air from entering the loft space? I am not sure if this will satisfy condensation requirements. If I leave a space at the bottom at the eaves, it is possible that any moist air that enters the loft could get under the insulation and cause condensation.
Advice would be appreciated.
Advice would be appreciated.