When assessing whether a residential building will overheat, CIBSE Guide TM59 should be used. This is not only considered a robust design methodology step, but is a requirement for London Plan and the new Part L 2021.
As EPC/NABERS/Energy Auditors and M&E Consultants, we often visit buildings to review the Building Management System (BMS) to establish whether the operations of a building are contributing to high energy usage.