Describes the results of the experimental evaluaton of two precast concrete sandwich panels. States that for best results for precast concrete walls, the air barrier must be sufficiently airtight to achieve static pressure equalization and there must be sufficient venting to achieve dynamic pressure-equalization. Similar results were obtained from research conducted on other wall systems. For precast concrete walls, these results are best obtained by minimizing the cavity volume and decreasing air barrier leakage before increasing vent area.
Describes a research and development project that has been started in order to generate design guidelines for PER walls. The three tasks covered are computer modelling, experimental evaluation and development of design guidelines. Describes the results of the experimental evaluation of an exterior insulation finish system. The systems were evaluated for air leakage characteristics, pressure equalization response and water penetration. Concludes that a wall designed to PER principles is more able to resist rain penetration.