August 2011: The Department for Communities and Local Government (CLG) have released the latest in its regular updates on the additional cost requirements of building homes to higher levels of environmental standards as required under the Code for Sustainable Homes (CSH). CLG’s press release states that “homes built to Code level 3 standards, average extra costs have fallen by almost three quarters in the last three years – falling from £4,458 in 2008 to £1,128 in 2010” – the extra costs being those required to achieve the Code level over the cost of building to the baseline building specification – in this case a Part L 2006 compliant building.
The research highlights that:
- A significant fraction of the costs of building to Code standards are incurred under the Energy and CO2 category of the Code.
- Typically meeting Code 3 requirements has involved improvement of the building fabric in combination with a solar thermal system or small PV array.
- But the standard could also be achieved through fabric improvement alone at a similar extra-over cost to strategies involving low carbon generation and several home builders cited a preference to avoid installing generator technologies on grounds of simplicity; and
- A fabric only approach at Code level 3 may become the norm
The research also highlights (pages 70/71) however that there are regional variations in the costs associated with meeting the targets, with London estimated to be up to 9% higher than elsewhere taking labour and material costs (from the industry price guide SPONS) into account.
The report highlights that as yet there is too little experience of building homes to higher levels of the Code however it is likely that biomass systems and community heating networks will be increasingly required to delivered the CO2 savings needed. In relation to London it must be noted however that :
- There are major concerns amongst air quality experts in relation to the use of biomass heat and power systems in London which will likely limit their use (new emission standards for biomass systems are currently being devised)
- Progress on the development of district heating networks in London remains slow despite the Mayor’s commitment to a 2025 25% decentralised energy target for the capital.