A glass furnace regenerator comprising: opposed pairs of side and end walls (16, 18) formed of refractory blocks; a plurality of buck stays extending vertically along an exterior of the side and end walls (16, 18); tie rods connecting opposite ones of the buck stays on the exterior of the side and end walls (16, 18) so as to compressively hold the buck stays against the side and end walls (16, 18), respectively; a pair of opposed U-shaped support beams each extending horizontally along an upper region of a respective side wall between the opposed end walls; a crown arch assembly forming an arched roof of the regenerator; and a rider arch assembly forming an interior floor of the regenerator and defining a lower space to allow ingress/egress of combustion air and/or combustion gases into/from the regenerator below the interior floor thereof, wherein the crown arch assembly is formed of adjacently positioned one-piece monolithic pre-cast crown arch structures of refractory materials comprising upper and lower concentric arcuate surfaces (40-1, 40-2) defining a substantially constant arch thickness therebetween and an opposed pair of side surfaces (40-3, 40-4), wherein each crown arch structure includes opposed ends (42, 44) received within a respective one of the U-shaped support beams, wherein each of the opposed ends (42, 44) includes a generally vertical end face (42-4, 44-4), upper and lower downwardly and outwardly convergent sloped mounting surfaces (42-2, 42-3, 44-2, 44-3), a substantially horizontal footer pad (42-1, 44-1), and a cross-wise step (42-5, 44-5) joining the upper arcuate surface of the crown arch structure to each of the upper downwardly and outwardly convergent sloped mounting surfaces thereof (42-4, 44-4). opposed pairs of side and end walls (16, 18) formed of refractory blocks; a plurality of buck stays extending vertically along an exterior of the side and end walls (16, 18); tie rods connecting opposite ones of the buck stays on the exterior of the side and end walls (16, 18) so as to compressively hold the buck stays against the side and end walls (16, 18), respectively; a pair of opposed U-shaped support beams each extending horizontally along an upper region of a respective side wall between the opposed end walls; a crown arch assembly forming an arched roof of the regenerator; and a rider arch assembly forming an interior floor of the regenerator and defining a lower space to allow ingress/egress of combustion air and/or combustion gases into/from the regenerator below the interior floor thereof, wherein the crown arch assembly is formed of adjacently positioned one-piece monolithic pre-cast crown arch structures of refractory materials comprising upper and lower concentric arcuate surfaces (40-1, 40-2) defining a substantially constant arch thickness therebetween and an opposed pair of side surfaces (40-3, 40-4), wherein each crown arch structure includes opposed ends (42, 44) received within a respective one of the U-shaped support beams, wherein each of the opposed ends (42, 44) includes a generally vertical end face (42-4, 44-4), upper and lower downwardly and outwardly convergent sloped mounting surfaces (42-2, 42-3, 44-2, 44-3), a substantially horizontal footer pad (42-1, 44-1), and a cross-wise step (42-5, 44-5) joining the upper arcuate surface of the crown arch structure to each of the upper downwardly and outwardly convergent sloped mounting surfaces thereof (42-4, 44-4).