By law, all new builds must have an EPC rating before they can be legally occupied. The EPC is essentially a measure of a building’s energy performance, and an assessor will use standardised tools and calculations to reach a conclusion.
Whilst an EPC does a pretty good job at estimating energy performance, it is just that – an estimate. To really get an accurate measure of energy performance, and in turn guarantee that your new build will be as energy efficient as possible, a more complex set of assessments need to be made.
What is energy modelling?
Energy modelling uses sophisticated software and methodology to predict actual energy performance through a variety of parameters. Intricate calculations – such as SBEM – and simulation programming help the assessor understand exactly how a building will retain heat or regulate air quality.
Standard assessments are limited to establishing the thermal performance of building fabric by calculating U-values and thermal bridging, so there is little emphasis, for instance, on assessing condensation risk. Energy modelling takes into account every mitigating factor.
However, energy modelling is expensive and not required under building regulations. With developers keen to cut costs, it is understandable that they might shy away from employing energy modelling as a way of calculating energy performance accurately.
But this is not always a wise choice.
Commercial buildings, for example, are built for a specific purpose which can change over time. In any case, an EPC rarely takes account of how the building will be used – an assessment will merely look at the overall performance of factors such as air quality, ventilation and heating.
For developers and landlords who want to improve the value of their properties, bringing in an energy performance specialist to do a full energy modelling survey will reap the rewards.
This should also happen in the event a new tenant wants to change the nature of the property to suit their purpose. Too often, occupants think of their requirements in terms of layout, brand identity, etc., but do not consider thermal performance or whether the building fabric has been designed to withstand the usage they intend.
Developers take note
Building physics is not wholly understood or appreciated by many in the property and construction industry. As we strive for excellence in the energy performance of our buildings, and take steps to ensure occupiers are not aghast when they receive their first energy bills, then energy modelling should become more intergral to the developing process.
At the moment, energy modelling is seen as something of a luxury. If industry professionals begin to take advantage of accurate and sophisticated energy assessment models, then the future could be brighter for all of us.
Murton & Co specialise in maximising the energy efficiency of properties. We have the experience and expertise to address specific needs in the design and improvement of buildings. Contact us to find out more.