The title, and basic theme, of this article probably will raise the ire of many design professionals. We all know and preach that sustainable design requires an integrated design approach, and that the design works together as a whole. A sustainably-designed building cannot be cut back in piecemeal fashion and expected to provide the benefits for which it is touted. However, as design professionals we know and experience regularly the wrenching effects of last-minute Value Engineering (VE) efforts undertaken to bring a project back to within an Owner’s stated budget. During the typical VE exercises, the Owner looks at (supposed discrete) elements of the design and appraises each for its “cost effectiveness.” The Owner scans down the line items on the Bid Tabulation (or latest design cost estimate) and asks “Where can I save money?” His perspective is that of someone ordering off anà la carte menu. The bottom line is simply the sum of all the elements. Ensuing discussions of the “integrated design” and how it cannot be “violated” usually end up with the Owner’s glazed-over look, and his ultimate response, again, comes forward: “Where can I save money?” This paper describes how a little basic sensitivity analysis can be used to show the appropriateness of the original design and can stave off the often ravaging effects of the typical VE process. It also shows that such sensitivity analysis is necessary if one is to obtain a good understanding of the design options available and the relative merit of each.
First, let’s review with basic tools of sustainable Design: (a) Building Energy Simulation (BES) using computer modeling and (b) Life Cycle Costing (LCC) techniques. These are basic to any Sustainable Design Professional’s “tool kit.” We will also see how the two of these are used in conjunction with each other to create a BES/LCC model that allows one to quantify design decisions. Owners are not familiar with BES, LCC, or the combination of these into a BES/LCC model, certainly not to the degree that design professionals are. Owners need to be educated in all these areas so that they can be made aware of the value of green design.