SBEM Calculations made Easier

SBEM Calculations are a method of showing compliance with Part L2: Conservation of Fuel & Power, of Building Regulations for non-dwellings otherwise known as commercial property. SBEM calculations look to evaluate that the ‘actual’ building concerned performs better, in terms of efficiency, than a ‘notional’ building which conforms to the current standards set by Legislation. The notional building is the same size and orientation as the actual building and the activities performed within each individual zone are also identical, the only things that do differ are the percentage glazing used within the calculations and the M&E services such as heating, cooling, ventilation, hot water generation and lighting.

Within the SBEM Calculation the notional building will present a Target Emission Rate (TER) in KgCO2/m² per annum and as this suggests this is a target that the actual building must not be greater than in order to demonstrate compliance with Part L2 of UK Building Regulations. The actual building will present a Building Emission Rate (BER), if BER ≤ TER then the building concerned complies with the regulations and the SBEM Calculation is successful.

There are a couple of other hoops that must be jumped through in order to gratify Building Regulations such as limiting u-value standards W/m².K for all external elements, efficiency of heat sources, power consumed through mechanical ventilation, lighting and air tightness of the building. The SBEM Calculation report will demonstrate whether these factors have been met.

Producing a building which merely complies to minimum standards will almost certainly not be enough to give a successful result of any SBEM Calculation, Building Regulations   have sought to vastly improve energy performance of new buildings in the UK and minimum standards must be largely improved upon in order to achieve a favourable outcome. Whether it is improved u-values, air tightness or lighting efficiencies which are implemented, a situation of robbing Peter to pay Paul is often the case which we at L2 Energy see on a daily basis.

On many occasions properties will not pass an SBEM Calculation without the introduction of renewable energy such as Photo-voltaics, Air or Ground Source Heat Pumps, Solar Thermal or Combined Heat and Power (CHP) Plant, all of these can be modelled into the SBEM calculation tool to identify the most suitable solution for a given site and client.

To achieve success in executing an SBEM Calculation it is prudent to make the building as thermally efficient as economically possible in the first instance, this will provide an excellent starting point. Ensure that the building has excellent air tightness of around 5 m³/hr.m² at 50pa or less. Following this, efficiency of m&e installations is key. The most thermally efficient building is only as good as the efficiency of the systems within so ensure that the lighting loads are optisimised with technologically advanced switching applied and heating and cooling efficiencies are maximised within budgetary constraints.

L2 Energy Consulting have a huge wealth of experience in achieving compliance for a whole manner of differing building types from schools, hospitals and leisure to 10 storey office blocks, flagship industrial facilities and large hotel developments. Whatever the scheme, we will find a solution.

Visit www.l2energy.co.uk/sbem-calculations.html for further information on SBEM Calculations and obtain a competitive quotation.