1. Low thermal mass

The density of the materials used in a structure strongly affects daytime overheating and the long-term retention of heat or cool in the structure. Lightweight structures such as SIPS and timber-framed buildings respond far quicker to high exterior temperatures. Higher density structures such as masonry and concrete respond far more slowly and peak daily internal temperatures remain lower on even the hottest days of the year.

2. Large areas of glazing

High proportions of glazing above 35% of the total wall area on east, south or west building elevations can be a significant cause of detrimental solar gains in spring, summer, and autumn. Where increased levels of glazing are desired, solar shading should be investigated and engineered to ensure fully functional and appropriate use for the building type.

3. Poor natural ventilation

The poor ventilation of spaces, particularly at night-time, in domestic dwellings is a great cause of overheating in homes. More generally, a lack of air movement or cross-ventilation in buildings can quickly become a nuisance and lead to high levels of discomfort. Single aspect buildings such as flats are a particular example, and the use of purge ventilation should be considered at the earliest stages of design to save costs later!

The way forward

One of the most effective ways to better understand the potential overheating risks of your development as designed is to use dynamic thermal and ventilation modelling from as early as possible in the building’s design process. Costs vary based on the building size and complexity, but for as little as £1,000 +VAT you can have a detailed first pass of the design and quickly identify room-by-room where any issues may lay. Once digitally modelled, as the design develops, an intelligent and focused approach can be taken providing feedback to the design team as to appropriate changes with a high level of confidence in performance once built.