Dissonance in Building Services Guidance: Implications for Energy Consumption

Building designers rely on a plethora of design guidance beyond compulsory building codes or regulations. However, it has been noted that guidance can be conflicting or contradictory. There is also evidence that design teams opt for ‘the safe option’, or that which colleagues have used. This is known to have led to the over-engineering of buildings and systems, potentially leading to unnecessary energy use, in direct conflict with the low carbon agenda. To quantify the potential scale of the impact, we investigated the energy use of commercial swimming pool halls, using the full-range of common design standards. Swimming pools were chosen due to their high-energy demand and because there are many guidance documents available from different sources. We found that different standards (which revolve around temperature, humidity and ventilation rate) produce designs with very different energy consumptions. Furthermore, the optimal ventilation rate (derived from a physics-based approach) was found to be far from values presented in guidance documents. Use of this new rate implies a 90% reduction in energy use, compared to the most conservative guidance, confirmed using measured data. This suggests this is a real issue and the existence of such contradictory guidance runs against the low carbon agenda.