Roof voids must be ventilated in order to stop warm air condensing on cold surfaces as condensation encourages rot and mould growth. The air path dimensions shown above are the minimum widths required for clear, continuous air spaces. Compliance with these ventilation standards is required on all buildings, except those constructed without ventilation provision or which pre-date Buildings Regulations. However, Swish recommend that adequate ventilation is provided on all refurbishment projects regardless of age.
Swish ventilators for roof voids are covered by British Board of Agrément Certificate No. 91/2620. When used in accordance with the Certification, Swish ventilators will satisfy all statutory Building Regulations in England, Wales, Scotland and Northern Ireland.
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