What to know before investing in mechanical ventilation with heat recovery (MVHR)
WORDS SOPHIE WARREN-SMITH
Ensuring a supply of clean, fresh air throughout a home is essential for good health and comfort. It can be done by the passive movement of air through doors and windows – a low-energy strategy that relies on good building design and outdoor air with minimal pollutants to be most effective. With mechanical ventilation, fans powered by electricity bring air from the outside in, and vice-versa, so the potential issue of poor-quality air is overcome through filtration. Include a heat exchanger and the incoming airflow is kept warm too. To be cost-effective and to perform well, this method must also be carefully designed.
CLEAN, FRESH AND WARM
Kept in a loft, basement, plant room or utility room, the air-handling unit of an MVHR system is its hub. It’s roughly the size of a domestic gas boiler and connects to a series of ducts that are attached to extraction and supply points throughout the home.
Stale air is drawn out of each room at the extraction point, passed through a run of ducting to a heat exchanger and expelled outside. The heat exchanger extracts warmth from the outgoing air, transferring it to fresh, incoming air that flows through a separate run of ducting into the rooms. Filters in the main unit remove particles from the outdoor air so that it is free from pollutants.
‘The process promotes a healthy indoor environment and reduces the need for additional heating, leading to low energy bills and carbon emissions,’ says Sean Ronnie Hill of Rise Design Studio (risedesignsstudio.co.uk).
A TIMELY INTERVENTION
