Like drainage, hot and cold water supplies, and electrical cable runs, ventilation ductwork benefits from a bit of forethought. Unfortunately ventilation is often left until the last minute – just stick in a cheap extractor fan and a bit of Flexi at the end of the job. Unlike drain runs and hot water, it’s not always obvious when ventilation ductwork has been done badly. That’s why a fan test is so important – you can’t immediately tell when the fan isn’t working as efficiently as it needs to.
Much of the time, builders get away with this. Why? Because the homeowner doesn’t insist on seeing a Flow Rate Test (PEATA) certificate or commissioning notice. A Flow Rate Test certificate will confirm instantly whether the airflow around your home is sufficient to meet current building regulations – and keep your family healthy.
Poor or inadequate ventilation leads to mould growth, often in bathrooms and behind furniture. This mould is linked to a variety of health problems, including breathing difficulties such as asthma, as well as allergies and skin problems.
Planning ventilation at the beginning of the job ensures that the ducting can be fitted properly. Correctly-planned ducting has a huge effect on the performance of your extractor fan or cooker hood. Poorly-planned ducting means that your extractor fan won’t work as it should, and usually means that it won’t meet current legal requirements for airflow rates. Part F of the building regulations specifies things like maximum duct lengths and number of bends allowed. Trying to squeeze ducting in at the end of the job usually involves compromises, and often an untidy snake of flexible duct jumbled in a loft or jammed into a ceiling void.
It’s easy to avoid this. Use a PEATA-registered contractor, plan the duct runs in advance, and ask for the Flow Rate Test (PEATA) certificate.