ABSTRACT
This chapter provides good practice techniques and information on the need to provide ventilation to areas including the converted roof, habitable rooms and wet rooms. It explains how to ventilate a habitable room; and third, the ventilation requirements if a bath/shower or WC are to be installed. The majority of existing roofs will be cold roofs, designed with insulation laid along the ceiling joists and well ventilated to offer maximum air flow in the roof space to avoid timber decay and mould growth through dampness from condensation and rain. To provide adequate ventilation to a roof you first need to be aware of the roofing felt/underlay that is in place, if any, and its type and condition. Ventilation openings should be provided to each void, at both high and low level, to allow free air movement through the gap between the insulation and the underlay.
