Improving the energy performance of existing homes

According to the Sustainable Development Commission, energy used in existing homes accounts for 27 per cent of all UK emissions and around 85 per cent of the existing stock will still be in use in 2050.

Refurbished tower block in Sandwell. Photo by Sustaining Tower Blocks

Improving the energy efficiency of existing homes represents one of the biggest challenges and opportunities for local authorities.

Taking action can also help enable buildings to cope more effectively with the impacts of climate change (for example hotter drier summer conditions and more extreme weather such as flooding), provide opportunities for the take-up of low carbon energy systems such as district heating or micro generation and deliver savings on fuel bills, which is particularly important for those households experiencing fuel poverty. These issues and benefits apply equally to non-domestic existing buildings.

The technologies already exist to enable significant improvements in energy efficiency of existing buildings. These include:

• insulation - walls, loft, tanks, floor and pipes
• draught proofing
• secondary and double glazing - or even better emerging true vacuum double glazing ,which can be used for re-glazing sash windows, for example
• ‘A’ rated boilers and improved heating systems and more efficient controls, lighting and appliances, which will support further reductions in demand

Measures such as external over cladding and micro-generation situated on buildings can address aesthetic or design concerns, particularly in conservation areas. The impact of these works must be assessed to ensure a workable solution can be delivered. This may, for example, include externally insulating those areas not in public view. In some circumstances, upgrading may be limited to fitting windows with secondary glazing.

As well as improving the energy efficiency of existing homes, there are also opportunities to introduce renewable and low carbon technologies. The Energy Saving Trust provides information on the costs and payback of different interventions for home owners. The Sustainable Energy Academy has an old home superhome programme that promotes sustainable refurbishment and provides examples.

Camden Council in London has worked with University College London researchers to refurbish and monitor the performance of a large Victorian house. It was refurbished to achieve an 80 per cent reduction in carbon emissions and has achieved a code for sustainable homes level 4 rating.

Kirklees Warm Zone

Kirklees Council, in Huddersfield, is the first local authority in the UK to offer free loft and cavity wall insulation to every home suitable for its installation.

Their Warm Zone project should save around 40 000 tonnes of CO2 a year by 2010. The project has won an Ashden Award for Sustainable Energy; whose case study shows how they set up, manage and finance the project.

Read more about Kirklees Warm Zone.

Photo by Septuagent

It is not just individual dwellings that can be refurbished. The 1960s Lyng Estate in Sandwell contains a number of tower blocks that have now been refurbished to enhance their overall environmental performance. This included external insulation and improved daylighting. Sustaining tower blocks provides guidance and advice on the refurbishment of residential tower blocks in the UK. A european funded project led by the Aarhus school of architecture provides examples of sustainable refurbishment of social housing in Europe.

The role of green infrastructure in supporting the enhanced energy performance of adjacent buildings should also not be overlooked. Well-designed planting within new public spaces and street trees can provide additional shelter in existing urban areas, but getting this right depends on the balance of over shading between seasons, providing shelter from prevailing winds and proximity of trees and their roots to drainage and foundations.

Improvements in energy performance will depend on widespread take-up of sustainable refurbishment of existing buildings. Although this will benefit from a central government policy lead there is much that can be achieved at the city level, going far beyond simply tackling properties in public sector ownership, although this is a good start.

Neighbourhood management and local authorities’ responsibilities for housing renewal bring strong opportunities for sustainable refurbishment. They can also play a key role in co-ordinating take-up of funding programmes such as Carbon Emission Reduction Target (CERT) or bulk purchase of materials and by undertaking studies into the performance of existing buildings.

At a city scale, local authorities should liaise with energy supply companies to establish what their responsibilities are for providing local energy efficiency measures via CERT funding, before identifying their own strategies. Local authorities have responsibilities as the building control authority and can also use their planning powers to require that efficiency is addressed as part of renovations on homes. Uttlesford district council is already doing this. And local authorities have a frontline role in advocating low-carbon lifestyles and promoting exemplar retrofit schemes - for example see Brighton’s eco open house weekend – as well as in engaging local private landlords and building owners in sustainable refurbishment.

An important measure to consider at the neighbourhood scale is the provision of district heating systems primarily to serve existing housing where densities support this. It is not generally widely known that this can be financed through existing funding streams such as the Renewables Obligation (RO) and CERT even though capital grants towards them are available from these and other sources. The CERT scheme will support the reduction of heat used by the average UK home from 13 to 9Mwhrs/home/year. However, reducing the impact of heating demand further could be achieved by establishing district heating systems sourced from the waste heat currently available from existing power stations generating electricity. The National Housing Federation provides a useful overview of the CERT and other funding opportunities available.

Local development frameworks and guidance documents should highlight the importance of new energy infrastructure linking in to existing buildings, as well new developments funding energy efficiency improvements in existing homes so as to tackle this major energy consumer. The emerging Heat and Energy Saving Strategy considers and looks to resolve some of the institutional barriers which have prevented action on this date.

Priority: reduce energy demand
Tags: energy, cities and towns, neighbourhoods, buildings and spaces