Improving commercial building performance with air tightness
There are many potential benefits in air tightness to a building operation including energy use, thermal comfort, acoustics and air quality; benefits that could be realised if we pay similar attention to how air moves through our buildings that other developed nations already do. Some of the benefits are readily apparent whereas others are more subtle.
It is clearly wasteful to go to the expense of cooling hot air in summer just to blow it outside, yet this is what happens with many buildings. Perhaps less obvious is the potential to avoid expensive capital upgrade of air conditioning plant that is struggling to keep a space comfortable, by avoiding waste. Appropriate airtightness can improve occupant thermal comfort by preventing unwanted draughts and letting conditioning systems work as intended. Air quality can be impacted by proper air tightness helping to ensure that air is drawn from clean sources and properly filtered, as intended by the building designers. Where air can leak through – often so can sound! Again air tightness can also reduce external acoustic noise (e.g. from traffic) improving the indoor environment.
To realise these potential benefits we must be able to make the business case for air tightness in a compelling manner. This requires information relevant to building stakeholders – stories that matter - to enable informed decision making around the commercial building envelope. To find these compelling stories, the Sustainable Buildings Research Centre together with industry partners including AMP Wealth, Tremco, and Air Barrier Technologies are proposing case study assessments of air tightness upgrades to real commercial buildings. By measuring building operational performance before and after upgrade, the information to build the business case for air tightness can be provided to building stakeholders in a credible way.
As a first step in carrying out useful case studies the current state of knowledge must be known and a methodology developed to provide useful, robust and meaningful results. Under a City of Sydney Environmental Performance Grant the Centre has carefully developed the required methodology based on the latest understandings from Australia and overseas to measure and assess the impact of air tightness on building energy use and occupant comfort.
The next step is to implement the methodology on case study buildings. The Centre is searching for candidate building for study along with funding to execute upgrade and assessment. These case studies will provide the data to build the business case to unlock the potential within commercial building air tightness.