The 20 properties studied by Cartwright Pickard and MEARU were representative of the housing stock built by London’s biggest contractors for well-known housing associations, the major producers of housing in their boroughs.
The houses were designed and built to Code for Sustainable Homes levels 3 and 4, Eco homes ‘very good’ rating and in accordance with the Building Regulations.
The dwellings incorporated energy-efficient strategies such as high levels of thermal insulation, airtight buildings with whole-house ventilation systems and high energy performing windows. However the research findings revealed significant gaps between the designed and actual dwelling performance, both in terms of energy use and environmental performance.
The indoor air quality within the 20 dwellings was a particular cause for concern. The ventilation provision adopted at the dwellings’ design stage was not performing adequately, with problems identified relating to design, construction quality, installation and commissioning, occupant interaction and maintenance.
Internal carbon dioxide (CO2) levels are used as an indicator of air quality – while CO2 concentrations would need to reach extreme levels to be directly harmful to humans (4,000ppm-plus), levels above 1,000pm (parts per million) are seen as an indicator of poor ventilation.
This can have consequences through the accumulation of pollutants such as VOCs given off by modern building materials and furniture etc., as well as increased moisture levels leading to dust-mite proliferation and mould growth, which can lead to asthma.
This has set the industry on a path to unintended health consequences, with problems caused by, for example, inadequate ventilation, evaporation of volatile chemicals into the air, and reduced standards of space and light. The resulting health risks are both physiological (respiratory disease, diminished immune system, diabetes, obesity) and psychological (seasonal affective disorder, depression).
Europeans spend 85-90 per cent of their time indoors, whether at home, work, school or leisure. Over the years there have been major changes to building design and materials, to the furniture, finishes and equipment we put into them and to the ways in which we use them. At the outset of the 20th century approximately 50 materials were used to construct buildings.
By the end of the century this list had grown to around 55,000, half of them synthetic. Compounds implicated in indoor air quality toxicity are emitted from the building materials, furnishings and fittings, cleaning products, and somewhat ironically even air fresheners. One result has been to amplify the effects of indoor environments on our health.
Read the full report here