Ms Sarah Neary:

As the Secretary General has said, the building regulations are performance based around energy efficiency and CO2 emissions.

In setting standards, we are technology neutral. It is up to the designers of public or private buildings to choose the heating systems that are most suitable for overall compliance.

Setting performance requirements in the building regulations is done through a cost-optimal analysis. As Mr. McCarthy explained, that is a life-cycle cost which takes into account the capital and operational costs over a 30-year period. Mr. Armstrong is involved in producing cost-optimal figures on a five-year basis. They show, in cost-optimal curves, the point at which our regulations should be set. Currently, that point allows a number of forms of heating system to be used, for example, gas boilers, photovoltaic solar panels and heat pumps. These would meet the CO2 emission and energy performance requirements under Part L because they take into account costs over the capital and operational periods. Given the volume of houses and other buildings currently required, keeping a broad supply chain available is important.