The CIBSE TM59 ‘design methodology for the assessment of overheating risk in homes’, launched in June 2017, presented a new challenge for the design of homes, in particular apartments and on sites that are constrained by noise and poor air quality. It is the industry’s response to increased reports of overheating in new build homes.
The policy was formally adopted in London in October 2018 and made the need to review overheating risk at concept stage a critical part of the design and planning process for high density residential developments. In addition to noise and air quality constraints, large windows, security risks, health and safety considerations, high levels of insulation, planning carbon targets, communal heating systems and climate change all work towards both increasing the risk of overheating and limiting the mitigation options available.
More recently Central Government confirmed their intention to regulate overheating in homes more vigorously, upgrading the widely recognised as weak overheating check in Part L of the Building Regulations to a method that aligns with CIBSE TM59. Consultation documents should be issued before the end of this year.
At Hilson Moran, we responded to this need to address overheating with a parametric optimisation tool called PATIO that assesses multiple permutations of feasible mitigation measures on initial designs and presents the most thermal and cost-effective solutions to the developer and project architect.
PATIO (Parametric Analysis Tool for Iterative Optimisation) provides a range of solutions that achieve CIBSE TM59, daylight and carbon emissions and planning regulatory compliance, applying passive measures and testing noise attenuation options where required. It enables multiple dynamic thermal modelling simulations to test a number of design parameters determined by the architectural concept, the site context and cost per square foot, then filters compliant results in optional ranges for each design mitigation measure.