The thermal resistance provided by un-insulated brick walls (R-3 to R-5) is often insufficient for occupant thermal comfort and energy efficiency in most climates. Retrofits to brick buildings are usually conducted from the interior due to both financial and social pressure to preserve the exterior façade. This seminar will focus on the thermal and hygric behavior of brick masonry walls with interior retrofit strategies. Key inputs that affect results and a methodology to comply with failure criteria are discussed. Analysis and results from research conducted by SWA will be shared.