IBHS conducted tests at the IBHS Research Center on siding materials in order to characterize the embers, in terms of mass and size, that are produced when these wall assemblies burn. Shown is an ignited wall assembly and an attached roof covering during a recent test. Developing a better understanding of the characteristics of embers produced by burning structural and vegetative fuels will increase our knowledge of their potential threat to the built environment. The black background is used to facilitate ember-tracking analysis of video collected during each test. Field investigations have shown that embers from burning structures, as well as burning vegetation, can put nearby buildings at risk of igniting. Knowing what type of embers are generated when common structural materials burn will ultimately help us improve our guidance for homeowners and communities.