Over the past ten years there has been a race to increase the insulation and air tightness of UK homes in a bid to reduce energy use and improve warmth and comfort. One of the unexpected consequences of this has been a deterioration in indoor air quality, which has been linked to chronic obstructive pulmonary disease pneumonia, lung cancer, asthma and coughs and colds by, amongst others, the British Lung Foundation. Richard Soper CBE, from Unico Systems outlines how effective ventilation can turn homes into health and wellbeing safe havens.
Ventilation is often one of the last considerations when it comes to designing and building homes in the UK. In fact a recent study by the Ministry of Housing, Communities & Local Government found that only two of 55 naturally ventilated homes met the Approved Document F of the Building Regulations for indoor air quality with respect to both trickle ventilator provision and intermittent extract fan air flow rates. Of those with continuous mechanical extract, only one of 25 homes met those same requirements.
One of the key ways of avoiding under provision is to place the heating and ventilation system in its rightful place at the centre of any development. It is the heart and lungs of a building, allowing it to breathe, adapt to temperature variances and filtering out pollutants.
Ventilation
Typical pollutants that contribute to poor indoor air quality include microscopic dust and dirt particles, carbon monoxide, nitrogen oxides and sulphur dioxide. Generated through cooking, cleaning and building materials it is impossible to eradicate these at source, however effective ventilation can mitigate the effects. Opening windows and doors is one way of doing this but is often impractical in the cooler months when indoor pollutants are at their worst and is a A picture containing building, white, sign, boat
Description automatically generated security risk for long periods in the summer, particularly at night. In winter, the cooler outdoor air needs to be tempered before being introduced to the building. One way of doing this is to integrate heating and ventilation.
In a small duct system such as Unico, heat energy generated from an air source heat pump or boiler is passed through the air handling unit, combined with outside air and distributed throughout the home through small, heavily insulated ducts. To ensure constant circulation the system uses a process known as aspiration creating a gentle suction around the outlets that draws room air into the stream of heated air. This delivers draft free heating with a temperature differential no greater than 1°C throughout the home. As well as improving air quality the delivery system means that there is no need for space-consuming radiators as warm air is delivered into rooms via small spotlight style outlets installed into the ceiling.
Filtration and air scrubbers
One of the benefits of using a centralised system to provide heating, cooling and ventilation is that air quality can be significantly improved at any time of the year through the addition of filters and air cleaners. High Efficiency Particulate Air filters are the most common in the UK and are designed to remove at least 99.97% of particles from the air. Electronic air cleaners such as an air scrubber is another option which neutralises smaller particles and mould that can cause illnesses. Finally, there are ultraviolet lights that destroy microbes in the heating ventilating and cooling system.
Tackling humidity
Humidity is one of those areas that is often overlooked when it comes to specifying a heating and cooling system, however, it plays a huge part in improving air quality, comfort and maintaining the health of a home. Removing humidity prevents the formation of damp and mould, major producers of air-bound toxins. The Unico System removes up to 30 per cent more humidity than conventional air conditioning and heating systems, which as well as improving air quality and preventing damp and mould growth ensures higher levels of comfort at warmer temperatures.
A recent study by the National Air Quality Testing Services revealed that indoor air pollution in UK homes is 3.5 times worse than outdoor air pollution. Yet effective ventilation is often seen as an optional add on, with those technologies that are used often failing to meet the minimum requirements of building regulations. Heating and ventilation are the heart and lungs of a building. By installing full-service systems alongside renewable technologies like heat pumps not only can you improve air quality, but also comfort all whilst reducing running costs.