A model for balancing sustainability vs. security

Doors and Hardware, Oct, 2007 by Rita Oberle, T. Pohlman, Kathy Roper

Acknowledging this interdependence, the decision maker eases the allocation process and the documentation of the decision process by considering the issues independently. In some cases, the funding dollars are from different appropriations or must be reported separately, thus requiring analysis of the interdependent factors independently. The methodology used in the model development assumes the components are independent and can be weighted against each other. Through a systematic analysis, even analyzed separately, of these interdependent issues, a much more efficient and cost-effective building can be produced.

The model can be considered a sustainability scoring tool. It is a helpful decision making tool. It is a simple, Excel-based program that allows for side-by-side comparison of multiple products. The model roots are derived from the Whole Building Design Guide and the LEED[TM] rating system. The user is free to define relevant weighting factors to match the requirements of each project. In searching a material/product database, the user defines relevant search factors.

The first three figures display a sample of the Credit factors, the Y axis in the total matrix, used in the pilot decision matrix. These credit factors were taken directly from the draft Whole Building Design Guide. Figure 1 shows Credit Factors for Sustainable Sites and Water Efficiency. Figure 2 shows Credit Factors for Energy and Atmosphere and Materials and Resources. Figure 3 shows Credit Factors for Indoor Environmental Quality and Innovation and Design Processes. Figure 4, the X axis of the total matrix, displays each product being evaluated with their weights for sustainability and security. In this sample Figure 4, the weights are equal at 50/50, but can be changed by the user. Under each product, the comparison variables and their weighting factors are presented. In this pilot model, only sustainability and security are used as comparison variables. First costs and life cycle costs are other factors recommended for comparisons. A third column is for the total of the comparative variables. Each total should add to 100 percent.

Under each element of Credit Factors, such as Figure 1 A: Sustainable Sites [SS] or B. Water Efficiency [WE], any required prerequisite is documented. The total of the contribution for that sub credit factor is summed at the bottom of that credit, such as Total Sustainable Site score or Total Water Efficiency Score, as shown on Figure 1. A Grand Total Score is computed at the bottom of the entire matrix for each product being evaluated. Given this design, all elements of the decision are documented and are visible for scrutiny or for challenge by other contributors to the decision. The most important aspect is that every contribution to the decision is visible.

Figure 4 displays the weighting factors and the individual contribution of each component. Again the most important aspect is the every contribution to the decision is visible. If a contributor to the decision process disagrees with a particular outcome, that contributor can re-evaluated each component of the decision, conduct sensitivity analyses of each component, or change the elements that contribute to the disagreement. However, all original rationale and any changes and their rationale must be documented in the comments section to insure a complete audit trail on the decision process.