Future developments

Building Regulations
Section 6 (Scotland) is projected to follow the example of Part L, but delayed by approximately one year. Part F (Northern Ireland) is likely to be similar to Part L and implemented in June 2006, with some differences relating to the prevalence of oil as a fuel.
Building Regulation Part L2 has undergone a major change in approach for the 2006 revision, using carbon dioxide emission rate as the primary indicator of energy performance. This is in line with the longer term national objective of moving towards a lower carbon economy in the UK as an attempt to combat global climate change.

The next revision, due to be enforced in 2011, is likely to maintain the same approach and methodology. However, further savings in CO2 emission rate will be required. The more stringent requirements will certainly necessitate U-values lower than currently required, and lower air permeability than presently allowed.

In addition, there is likely to be more emphasis placed upon renewable energy and control technology, for example:

• Low or Zero Carbon technologies, such as solar thermal (water heating) and building-integrated photovoltaics.
• Sophisticated automatic controls for lighting and building management systems (BMS).

Beyond Compliance

Significant improvements in energy performance, beyond mandatory levels, are currently feasible from a purely technological perspective. Justification for low energy designs is however more difficult on economic grounds. It is possible that uncertainties in UK energy supplies may force prices up in the future such that additional spending on insulation, air-tightness, efficient plant and controls, and low/zero carbon technologies may be justified using a simple payback period approach. At present, the arguments are more likely to be grounded on demonstrating a concern for the environment and setting an example to others.

The options for achieving low energy buildings with steel envelopes include:

• Increased fabric insulation to reduce planar heat flow
• Enhanced detailing at junctions to reduce thermal bridging.
• Air-tight construction (e.g. 1 m3/h/m2 is possible).
• External shading to reduce overheating whilst admitting low winter sun.
• Advanced cladding coatings to reduce solar heat gains.
• Heat exchange devices to reclaim heat from ventilation air.
• State-of-the-art boilers and chillers, with associated BMS controls.
• Low energy lighting equipment and advanced lighting controls.
• Use of ground source heat pumps, geothermal heating, photovoltaics and solar thermal arrays.

Many of these do not have any significant cost penalty and the operational cost saving are significant.

Additional benefits of specifying a higher thermal performance building include an element of futureproofing against rising energy costs, and the potential for higher rent or resale value.