Energy efficiency of housing in the UK relates to the efforts and policies aimed at decreasing the usage of energy and generation of greenhouse gases in the domestic building stock of the UK. The UK housing sector is one of the main consumers of energy and emitter of greenhouse gases.
Energy efficiency in new homes is mostly governed by building regulations, but old homes are governed by such policies as energy efficiency policies, energy efficiency standards, energy performance certificates, and financial incentives. There have been developments in energy efficiency policy since the 2000s, particularly in the development of new building regulations and energy standards for new homes.
Carbon emissions Although carbon emissions from housing have remained fairly stable since 1990 (due to the increase in household energy use having been compensated for by the 'dash for gas'), housing accounted for around 30% of all the UK's carbon dioxide emissions in 2004 (40 million tonnes of carbon)House of Commons – Environmental Audit – First Report up from 26.42% in 1990 as a proportion of the UK's total emissions. The Select Committee on Environmental Audit noted that emissions from housing could constitute over 55% of the UK's target for carbon emissions in 2050.
A 2006 report commissioned by British GasDomestic Carbon Dioxide Emissions for Selected Cities , British Gas, published 20 February 2006. Retrieved 9 August 2007. estimated the average carbon emissions for housing in each of the local authorities in Great Britain, the first time that this had been done. This indicated that housing in Uttlesford (Essex) produced the highest emissions (8,092 kg of carbon dioxide per dwelling). This was 250% higher than housing in Camden (London) which produced the least (averaging 3,255 kg). Among the 23 towns included, Reading had the highest emissions (6,189 kg), with Hull the lowest (4,395 kg). The variations are due to a number of factors, including the age, size and type of the housing stock, together with the efficiency of heating systems, the mix of fuels used, the ownership of appliances, occupancy levels and the habits of the occupants.
Zero carbon ambition In the December 2006 Pre-Budget Report,Pre-Budget Report 2006: Index the Government announced their 'ambition' that all new homes will be 'zero-carbon' by 2016 (i.e. built to zero-carbon building standards). To encourage this, an exemption from Stamp duty land tax was to be granted, lasting until 2012, for all new zero-carbon homes up to £500,000 in value.Budget 2007: Speech
Whilst some organisations applauded the initial announcement of the scheme, in the pre-budget statement from the then UK Chancellor, Gordon Brown, others are concerned about the government's ability to deliver on the promise.Green Building
Domestic energy use In 2003 the housing stock in the United Kingdom was amongst the least energy efficient in Europe. In 2004, housing (including space heating, hot water, lighting, cooking, and appliances) accounted for 30.23% of all energy use in the UK (up from 27.70% in 1990).DTI The figure for London is higher at approximately 37%.
In view of the progressive tightening of the Building Regulations' requirements for energy efficiency since the 1970s (see the history section below), it might be expected that a significant cut in domestic energy use would have occurred, however this has not yet been the case.
Although insulation standards have been increasing, so has the standard of home heating. In 1970, only 31% of homes had central heating. By 2003 it had been installed in 92% of British homes,DTI leading in turn to a rise in the average temperature within them (from 12.1 °C to 18.20 °C).DTI Even in homes with central heating, average temperatures rose 4.55 °C during this period.
At the same time, the increase in the number of households, increasing numbers of domestic electrical appliances, an increase in the number of light fittings, reduction in the average number of occupants per household, plus other factors, had led to an increase in total national domestic energy consumption from around 25% in 1970 to about 30% in 2001, and remained on an upward trend (BRE figures).
The figures for energy consumed by end use for 2003.DTI Space heating - 60.51% (57.61% in 1990) Water heating - 23.60% (25.23% in 1990) Appliances and lighting - 13.15% (13.4% in 1990) Cooking - 2.74% (3.76%)
The Green Deal
The Green Deal provided low interest loans for energy efficiency improvements to the energy bills of the properties the upgrades are performed on. These debts are passed onto new occupiers when they take over the payment of energy bills. The costs of the loan repayments should be less than the savings on the bills from the upgrades, however this will be a guideline and not legally enforceable guarantee. It is believed that tying repayment to energy bills will give investors a secure return. The Green Deal for the domestic property market was launched in October 2012. The Commercial Green Deal was launched in January 2012 and released in a series of stages to help with the varying needs and requirements of commercial properties.
Building regulations
The 1965 Building Regulations introduced the first limits on the amount of energy that could be lost through certain elements of the fabric of new houses. This thermal performance was expressed in the imperial units of the time (the amount of heat in BTU lost per square foot, for each degree Fahrenheit of temperature difference between inside and outside). The 1965 regulations were the first set of truly nationwide standards, prior to this local authorities set their own local regimes. Part F of the 1965 regulations defines minimum thermal performance, and schedule 11 of the same document gives examples of compliant methods for builders and architects to refer to. While novel at the time, by modern standards these limits set quite a low target, unfilled cavity walls, 2 inches of loft insulation and uninsulated concrete floors were deemed adequate for the reference standards. The 1972 regulations retained the same standards but converted to metric units (mm) and the modern u-value (the amount of heat lost per square metre, for each degree Celsius of temperature difference between inside and outside).
In effect, the Target Insulation was u-values of 1.42 W/m2·K for the roof and floor and 1.7 W/m2·K for external walls. Modern performance standards require values less than 20% of this. This u-value approach is slightly regressive in that richer people live in bigger houses which tend to have a lower ratio of surface area to floor area, although they are often detached, which can offset the advantage over smaller row houses.
These first limits were tightened following the 1973 oil crisis, and on several subsequent occasions, including the addition of limits for doors and windows in the year 2000 that effectively required double glazing for the first time. (see below). Despite this, UK insulation levels have been introduced later or remained lower compared to the EU average.
Changes in 2006 The energy policy of the United Kingdom through the 2003 Energy White PaperBERR – Redirect articulated directions for more energy efficient building construction. Hence, the year 2006 saw a significant tightening of energy efficiency requirements within the Building Regulations (for earlier regulations, see separate section below).
With the long-term aim of cutting overall emissions by 60% by 2050, and by 80% by 2100, the intention of the 2006 changes was to cut energy use in new housing by 20% compared to a similar building constructed to the 2002 standards. The changes were the first to the regulations brought about by the desire to reduce emissions, though some have raised doubts about whether they will actually achieve the 20% cut (see criticisms section).
In the 2006 regulations, the u-value was replaced as the primary measure of energy efficiency by the Dwelling Carbon Dioxide Emission Rate (DER),Dwelling Carbon Dioxide Emission Rate an estimate of carbon dioxide emissions per m2 of floor area. This is calculated using the Government's Standard Assessment Procedure for Energy Rating of Dwellings (SAP 2005).Standard Assessment Procedure for Energy Rating of Dwellings 2005, Building Research Establishment
In addition to the levels of insulation provide by the structure of the building, the DER also takes into account the airtightness of the building, the efficiency of space and water heating, the efficiency of lighting, and any savings from solar power or other energy generation technologies employed, and other factors. For the first time, it also became compulsory to upgrade the energy efficiency in existing houses when extensions or certain other works are carried out.
Some organisations have raised doubts over the claim that the changes will result in a 20% saving. Issues cited have included alleged problems with the calculation methods, the limitations of the modelling software, and the specification of the reference building used in the model. For example, a 2005 study sponsored by the Pilkington Energy Efficiency Trust indicated that the savings would only be in the region of 9%.Microsoft Word - Report A.doc
There are also concerns about enforcement, with a Building Research Establishment study in 2004 indicating that 60% of new homes do not conform to existing regulations.Assessment of Energy Efficiency impact of Building Regulations Compliance , prepared by the Building Research Establishment for the Energy Saving Trust / Energy Efficiency Partnership for Homes, published 10 November 2004. Retrieved 9 August 2007. A 2006 survey for the Energy Saving Trust revealed that Building Control Officers considered energy efficiency 'a low priority' and that few would take any action over failure to comply with the Building Regulations because the matter 'seemed trivial'.Part L1 - an investigation into the reasons for poor compliance , Energy Saving Trust, published 3 May 2006. Retrieved 18 May 2007.Time to put a stop to the disdain for regulations, Association for the Conservation of Energy, published March 2006. Retrieved 9 August 2007.
Further changes In December 2006, the government announced their ambition that all new housing should be built to zero-carbon standards from 2016;Pre-Budget Report 2006 , HM Treasury, published 6 December 2006. Retrieved 2 June 2008. i.e., that the carbon emitted during a typical year should be balanced by renewable energy generation. Despite being the first country in the world to adopt such a policyUK to leap from 'laggard to leader' on carbon dioxide emissions, The Independent, published 24 February 2008. Retrieved 2 June 2008. the initiative was generally welcomed by the industry in principle,HBF welcomes Government's environmental vision on housing , Home Builder's Federation, December 2006 press releases, published 15 December 2006. Retrieved 2 June 2008. despite some subsequent concern over the practicalities.Government's 2016 zero-carbon homes target 'too unrealistic', Architects Journal, published 6 March 2008. Retrieved 2 June 2008.Zero-carbon construction , M Briggs, RSPH, published January 2008. Retrieved 2 June 2008.
On 1 April 2011 the WWF resigned from the taskforce on Zero-Carbon homes, stating that 'the zero-carbon policy is now in tatters' after the Government unilaterally decided to change the scope of the 'zero carbon' policy to exclude some emissionsWhy we've resigned from the Zero Carbon Taskforce WWF UK, published 4 April 2011, accessed 4 April 2011 not currently covered by the building regulations. The UK Green Building Council estimated that the change, published at the time of the March 2011 budget, will result in only two-thirds of the emissions of a new home being mitigated.Government's U turn on Zero Carbon is anti-green and anti-growth UK Green Building Council, published 23 March 2011, accessed 4 April 2011