A Reality Based Cost-Benefit Analysis Of High Performance Residences: Part Ii

This research initiative attempts to determine, from real construction cost estimates, the cost challenge and expected payback period associated with building a high-performance residence in Victoria, BC. This was accomplished through: a simulated tendering process with local contractors, an energy analysis of a case-study residence (Part I of this research initiative), and an in-depth study into the variables governing time-to-amortization. The contractors provided quotes for an as-built "above code" residence (ACR), and a "minimum-code" residence (MCR) with the same floor plan (Note: The as-built above-code residence was not built or designed to any specific performance standard; however, it was found in Part I of this research initiative that when compared to the new BC Step code that it performed at a step 3 designation, bordering on step 4 performance). The results of the tendering process were then compared to the as-built construction costs of the residence. When compared to the MCR, it was found that the ACR has a cost challenge of approximately 22.5%, an energy advantage of 22.5 kWh/m(2)/year, and a payback period of over 79 years when a fuel inflation rate of 2% is considered. However, many of the components in the ACR assemblies were either for aesthetic appeal (metal-roofing), or comfort (floor-cavity insulation), and therefore it was possible to reduce the cost challenge to just 2.1%, while maintaining an energy advantage of 15 kWh/m(2)/year and step level 3 designation. This was dubbed the hybrid-residence as it employed a combination of above-code and minimum-code construction assemblies. Based on a simple mortgage increase calculation, it was found that the reduction in operational costs produced by the energy-efficiency measures for this residence services 87% of the mortgage increase taken on by the home buyer.