PPS 6 Planning Archaeology and the Built Heritage·Page 61·E18
Trickle ventilation in historic windows
Where trickle ventilation is required, conservation-compliant ventilators designed for traditional windows are available. Ventilation can be provided through alternative locations where window modification would be problematic.
In certain circumstances trickle ventilation will be a statutory requirement. There are a variety of ways to modify the designs of traditional windows to make this provision and there are ventilators available that have been specially designed to meet conservation criteria. Where difficulties arise it is as well to remember that the purpose of the ventilator is simply to ventilate the room; it is not a requirement that it be provided through the window. Other locations should therefore be assessed in difficult circumstances.
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