At the beginning of January, housing minister Yvette Cooper called for radical changes in housing to reduce carbon emissions. She also said that new technology needs to be developed to support “our Victorian terraces and 60s tower blocks. But a recent report by Tim Yates of the BRE Trust points out the significant existing potential for refurbishing many of our older buildings
An example of the conflict between high specification new build and the need to retain existing stock is the redevelopment in Nelson, Lancashire, where the local authority’s decision to demolish more than 400 of the existing 19th century houses in the Whitefield area was successfully challenged by the occupants with the support of English Heritage and the Prince’s Foundation.
A second example occurred in 2005 when many conservation groups raised concerns at the large-scale demolition plans of the then Office of the Deputy Prime Minister, which seemed to indicate a lack of joined-up thinking on sustainability and sustainable communities. These concerns were further highlighted by the publication in 2005 of the 40% House report (www.eci.ox.ac.uk/lowercf/40house.html) which advocated the demolition of up to 8 million houses, including a very large proportion of those constructed before 1919.
Considerable redevelopment of urban housing in the UK has been carried out since the 1980s. In many cases the regeneration programmes have seen existing buildings demolished and replaced by new build housing. However, the refurbishment of existing buildings may be a cost effective choice, and in many ways is a more desirable option. Such refurbishment can result in better quality housing for the occupiers, and reduced heat losses and it also retains the fabric of the structure along with the traditional urban landscape that forms such an important part of our built heritage.
There are countless examples of Victorian housing converted from single family occupancies into multi-residential units that demonstrates the flexibility of this type of property to meet the demands of changing demographic patterns and the trend towards smaller households. There are also exemplary case studies of Victorian terraced housing that have been refurbished to high standards of energy efficiency. Achievable standards of sustainable refurbishment of the existing housing stock can be benchmarked against current Building Regulations and Ecohomes ratings for new build.
Solid walled houses
Refurbishment of solid walled houses can achieve SAP ratings (Standard Assessment Procedure – the government’s standard method of home energy rating) equal to, or better than, those of new build properties complying with Building Regulations.
The potential for energy saving in an older property can be seen in a project carried out in the mid-1990s in Scotland. This was carried out by a housing association in 1996 and involved the full refurbishment and upgrading of a four-storey tenement building. The block was a mixture of one, two and three bedroom flats and during the refurbishment some remodelling was undertaken which reduced the number of flats from 51 to 48. Twenty-two of the flats were privately owned. External walls were solid sandstone and the ground floor was of solid construction. Heating was by gas and electric fires.
The measures included in the final specification were:
- mineral wool loft insulation
- internal insulation and plasterboard to external walls
- insulation to close walls and ceiling
- replacement timber frame double glazing
- kitchen and bathroom extract fans
- draught sealing of front doors of flats
- full gas fired central heating with back boiler (housing association owned flats)
- full gas fired central heating with combination boiler (privately owned flats).
A SAP analysis was carried out for the flats before and after refurbishment. The results from the two flat types estimated to have the highest and the lowest SAP rating after refurbishment are given in Table 1. The analysis showed that good SAP ratings were achieved. Annual space and water heating costs were estimated to have reduced by 64% and 62% for the second floor three-bed flat and the ground floor two-bed flat respectively. CO2 emissions were estimated to have reduced by 20% and 27%.
The clerk of works, interviewed shortly after work was completed, reported that there had been no real ‘buildability’ problems with the project. The main problem related to the position of the new boilers. The housing association preferred to fit back boilers in tenement flats because this does not require internal space and ventilation is simpler (i.e. via chimney flues). Other boiler types have to be vented via an external wall and in some flats there can be difficulties in finding such a position. Finding a suitable internal space for the boiler can also be problematic.