An efficient approach for thermal design of masonry walls using design charts and R-value multipliers

The effective thermal resistance of masonry cavity walls is affected by thermal bridging, which is common in connecting masonry veneers to structural backup walls. Therefore, a precise estimation of the R-value of masonry cavity walls is currently a time-consuming task, which lengthens the design process, especially in the early design stage where many design options (e.g. structural and thermal) need to be explored holistically. This paper presents an efficient approach for estimating the R-values of common masonry cavity wall configurations in the form of simple design charts and R-value multipliers. Parameters such as the block density, thermal insulation value, and the types of ties and shelf angles are addressed in this study. The approach simultaneously provides the mechanical (the masonry compressive strength, fm′) and thermal (R-value) properties of different cavity wall configurations, allowing designers to obtain appropriate structural and thermal properties during a preliminary design phase without using computer simulations.