When designing modern buildings, achieving the right balance between air permeability and natural ventilation is essential for ensuring energy efficiency, indoor air quality, and occupant comfort. Air permeability refers to a building’s ability to allow air infiltration through its envelope, which is influenced by materials, construction quality, and design. Effective natural ventilation utilises external air flow to regulate indoor air quality and temperature, thereby reducing reliance on mechanical systems. At Ratio Seven, we specialise in developing comprehensive solutions to optimise this balance, leading to healthier and more sustainable environments while complying with local regulations and standards.

SAP calculations for cooling systems in the UK rely on standardised assumptions, such as operating six hours daily at 24°C for three months, to simplify energy efficiency evaluations. However, these assumptions may not accurately reflect real-world usage, as actual conditions often demand lower set points and longer operation due to factors like the urban heat island effect. While the methodology does not extensively differentiate between cooling system types, it integrates crucial elements such as ventilation, insulation, and renewable technologies to provide a comprehensive assessment. Though simplified, these calculations necessitate detailed data input, ensuring a holistic view of the dwelling’s energy performance and carbon emissions.