The subject burner assembly disposes an air inlet along a base surface of a housing opposite from a radiant, multi-ply screen surface. Air enters the inlet for mixture with an associated supply of gas in a mixing chamber. An air/gas mixture exits the mixing chamber and enters a plenum chamber for distribution and combustion on the entire radiant surface. The multi-ply, radiant surface is defined by three separate screens having a predetermined weave pattern. A reverberator is spaced from the radiant surface and reflects heat from the exhaust gas toward the radiant surface.