Introduced in 2005 the new Building Regulations Part L has changed the scene as far as boilers are concerned. According to the new requirement, all boilers replaced or installed must be of high efficiency rating. This includes condensing and combination boilers which utilize a larger heat exchanger (or a secondary heat exchanger) to recoup some of the heat that would normally be released into the atmosphere with the exhaust gases. Since some of the energy can be reused, the boiler can generate the same amount of heat with less fuel.



The new requirements are much more demanding than previously in terms of the professional level of the system designer, the installer and the service engineer. The new systems are more integrated than old systems as all components are specifically designed to provide the right output (in terms of power) or demand the right input (such as in the case of heating controls). The engineer has to have good understanding in order to maximize the efficiency of the system.

Research shows that since the introduction of the new Part L, the domestic heating industry has made a major reduction in the amount of carbon emissions generated every year. Recent analysis conducted in the industry indicates that savings of around 2.4 million tonnes of carbon have been made since the new Building Regulations have been introduced. Furthermore, the analysis shows that had Part L not been introduced and with the industry relying on SEDBUK D rated systems, the amount of carbon emissions would have increased by over one million tonnes since 2005.

At current levels there is still large potential for reducing the carbon emissions generated by the domestic boilers in the UK. There are around four million old boilers which are significantly less efficient than modern SEDBUK A rated boilers. Replacing such old boilers with an A rated boiler can reduce carbon emissions by around 30%. Each home in the UK produces an average of 5 tonnes of CO2 per annum. Across the whole population, domestic heating accounts for around 16% of the UK's CO2 emissions.

The government is trying to encourage carbon reducing behaviour within the home heating sector. It has scrapped stamp duty for carbon neutral homes and has introduced the home information packs which have an energy performance certificate as part of the pack. However, the stamp duty benefit does not apply to the vast majority of inefficient homes around the country making it less effective. The home information packs (with their energy performance certificate component) also have drawbacks in that they are only produced when the house is sold, and thus not having enough of an impact at other times to encourage reduction in carbon emissions.

There are several alternatives to adopt that can further reduce the carbon emission resulting from domestic heating within the UK. The most effective among them is the application of renewable energy technologies, such as solar water heating. If just 10% of the new homes that the government plans to build between now and 2020 adopt such technologies, it is estimated that around 150,000 tonnes of carbon emissions would be cut on an annual basis.

There are several options for the government to reduce the carbon emissions from the UK housing stock and meet the challenging targets it set. It is important to note that any relevant plan would be met with a prepared and professional group of plumbing and heating companies that are investing in professional development and staff training for the new technologies.