A plaque for a radiant heating system can include a main body defining an outer surface and a plurality of pores defined within the main body, wherein at least some of the plurality of pores are disposed in a non-parallel relationship with at least some others of the plurality of pores, or wherein at least some of the pores are parallel with each other. A burner assembly including a plurality of adjacently arranged plaques reduces the ignition time and delay for adjacent plaques after the central plaque has been ignited.