Thermal Performance Impacts of Venting EIFS Assemblies

One of the key improvements in EIFS is the addition of a geometrically defined drainage gap in the continuous insulation layer to allow water that has penetrated the outer EIFS lamina to drain out by gravity to the exterior. The integration of this cavity has raised questions regarding its impact on the thermal performance of wall assemblies constructed with these vented EIFS. The objective of this research is to evaluate the thermal performance impacts, as a percentage reduction in the effective RSI-Value, of a vented EIFS assembly against a face-sealed EIFS and expand the results with respect to increased building height and wind velocities. It can be concluded from the results that a vented EIFS assembly with 2-inches of EPS foam insulation and 4-inches of fiberglass cavity insulation experiences a maximum reduction of 4% in the whole assembly’s effective RSI-value against a face-sealed EIFS assembly. Furthermore, increased wind speeds, caused by installing EIFS at higher elevations from the grade had negligible effects on the thermal resistances of the face-sealed and vented EIFS