A Sustainability Matrix Approach to Building Material Selection and Assembly Design

Abstract

The sustainable design of buildings, notably material and assembly selection is beginning to be embraced by design professionals. However, the environmental considerations of building design and material selection often rely on time-consuming, costly approaches such as life cycle analysis which often do not provide adequate information for designers to effect preventive engineering approaches in the early design stages. Less time consuming approaches are available, but their application to design is often difficult due to their subjective nature. The Sustainability Matrix Approach, based upon the work of Graedel and Allenby offers guidance to the building designer in the preliminary design stages through a combination of streamlined life cycle assessment and a series of checklists.

The series of checklists based upon core sustainability principles alerts the designer to environmental hotspots and can serve as a guide to redirect product and material choices to those that are environmentally preferable. To supplement the decision-making process, life cycle inventory data are used.

Using this approach to preliminary design, four wall systems were investigated: steel stud, wood stud, concrete block and strawbale. The results indicated that the environmental impact of the strawbale wall assembly was greater than anticipated largely due to the nature and amount of exterior and interior plasters used. The steel and wood stud wall assemblies, using the selected criteria, were found to be environmentally preferable to the strawbale wall assembly.

The sustainability matrix approach is a useful preliminary design tool for assessing the net environmental burdens of not only walls but other building elements as well. However, the sustainability matrix does not explicitly consider other important sustainability parameters that are not governed by material or system properties such as building durability. Nevertheless, the Sustainability Matrix Approach is a useful tool for learning about the difficult decisions required in designing environmentally preferable buildings.