All Credits: R-Value Optimization for Low-Slope Roofs  

Low slope roof assemblies are designed to meet code specified insulation values. However, systems are sometimes built such with a significant reduction in insulation value, through no fault of the contractor. The roof system delivered to the building owner can show up to a 30% reduction in the built insulation value versus the design due to thermal bridging. The talk shows R-value differences due to fastener densities and location within the system. The significant reduction in R-value due to thermal bridging and the dollar cost due to unrealized R-value is shown. The cost is contrasted with costs of fasteners and adhesives for many possible attachment scenarios. The long term energy efficiency and lost R-value costs are shown in terms of the costs/benefits of various roofing assemblies. Finally, other aspects of roof assembly construction, such as the use of vapor retarders, are reviewed from the perspective of R-value optimization.

Sponsored by GAF | Siplast