The concept of Housing Performance has been evaluated as part of the SURI Project because it is a widely used term but with little consistent meaning.
For example, a cheap and simple dwelling designed and constructed to last for a very short time but provide generally accepted comforts, shelter and safety could be considered ‘High Performance’. Many locations allow a life-span of only ten years to satisfy legal liability periods. A house that delivers its services very well over this period could be considered High-Performance. However it may not provide long term durability or economic viability, or may quickly fail at the end of its programmed life-span threatening investment, the local environment or even human safety.
A house that delivers exceptionally good thermal performance and zero-energy strategies through strict adherence to advanced technologies may be considered ‘High-Performance’. However it may be constructed from materials that have been sourced through questionable environmental practices, components that cause manufacturing related pollution in other locations, materials that require high levels of maintenance or materials not necessarily healthy for humans.
Selecting one technological quality over an ecological aspect; an economic advantage over a durability aspect or a local environment advantage over negative materials source implications is misleading when claiming performance. Therefore having High-Performance in one area with distinct negative implications in others can entirely negate the effort. This dilemma can also emerge within legislatory and regulatory objectives and rules for housing performance.
The term ‘High-Performance’ in house design and construction can therefore be very contestable.
To determine house performance targets for the SURI Project it has been necessary to define what performance relates to and what the objectives are, in order to establish a universally relevant measure of performance. This demands analysis of all of the underlying objectives, and identifying benchmarks that can be set for authentic performance evaluation across as many aspects of building as possible. This needs to also encompass all factors from the first design discussions through to end-of-life demolition, with every stage in between considered.
These parameters are by necessity part theoretical and part practical and are the subject of ongoing research and refinement. The SURI Project is to include a specifically designed test-bed house which will allow testing and evaluation of theoretical factors and the setting of technical benchmarks for a range of performance attributes. These cover such things as material and system performance, construction process performance, cost performance, thermal and comfort performance, human resource opportunity, economic performance and environmental evaluation from material source to final use and end-of-life.
Primary factors that we consider define performance in house design and construction include: