I am about to put rigid insulation into the ceilings of a number of attic rooms, having taken down the plaster to get at it (no insulation in there previously). The shape of the roof is sloping sections at each side leading to a flat section across the centre.
The sloping sides have plenty of ventilation through the eaves, but the central flat section has little draft from the sloping parts (mostly blocked from it by rafters), and no vents through the roof felt. Apart from leaving a 50mm gap, should I put in roof vents in this section of flat roof, or would a vapour barrier be better/suitable?
Similar question for the ceiling above the windows that stick out from these rooms and have a small flat section above - no ventilation for them, what is best insulation approach?
Thanks in advance,
The sloping sides have plenty of ventilation through the eaves, but the central flat section has little draft from the sloping parts (mostly blocked from it by rafters), and no vents through the roof felt. Apart from leaving a 50mm gap, should I put in roof vents in this section of flat roof, or would a vapour barrier be better/suitable?
Similar question for the ceiling above the windows that stick out from these rooms and have a small flat section above - no ventilation for them, what is best insulation approach?
Thanks in advance,