Architects and Specifiers

Ventilation for steep-slope roof assemblies is often misunderstood. One must not only understand the code requirements, but be able to translate them into real-world installations. Building codes have requirements for ventilation of steep-slope attics and enclosed rafter spaces. Balanced ventilation — nearly equal amounts of intake and exhaust — typcially provides efficient ventilation. Transitions between low-slope and steep-slope roof areas require more distinct intake and exhaust details than traditional eaves/soffits and ridges.

Thermal insulation is an important part of commercial roofing assemblies. The aim of this article is to examine the factors influencing the thermal resistance, known as R-value of polyiso. The prediction of long term R-value and the influence of climate, i.e. temperature, have been of significant interest over the past few decades as building energy budgets have increased in importance. Recent discussions as to what R-value the designer should use and the importance of ambient temperature are reviewed and discussed.

Wind uplift is a primary concern when installing a retrofit single-ply roof system (RSPRS) over a structural metal panel roof. ASTM E 1592 physical testing was performed on three test roof assemblies in order to determine the wind uplift resistance of an RSPRS installed over existing structural metal panel roof systems fastened directly into purlins. This paper presents the findings and conclusions of that analysis.Read the full paper Physical Testing for Wind Resistance of Retrofit Single-Ply Roof Systems Over Structural Metal Panel Roof Systems.View more white papers from GAF on our Architect & Specifier Education Resource Page.

Is thermal mass a lost art form after centuries of use in temperate regions?In building design, the thermal mass of a building enables it to store heat, providing "inertia" against temperature fluctuations. It reduces the impact of external daily temperature swings on internal heating and cooling requirements. This thermal inertia has been an on-off again topic of discussion for some time. Proponents of adding thermal inertia point to Mediterranean area buildings constructed with thick stone walls and ceramic tile floors etc. Such buildings have kept occupants cooler than lighter weight buildings in many temperate areas of the world for centuries. In the quest to improve the energy efficiency of buildings, further gains are becoming increasingly harder to come by.