Float glass forming chamber with externally supported roof

Apparatus for forming flat glass by the float process comprising an enclosure adapted to hold a pool of molten metal, means for delivering a stream of molten glass onto the molten metal, and means for drawing the glass along the pool of molten metal so as to form the glass into a ribbon, the improvement comprising:

• a roof portion of the enclosure formed by a plurality of refractory slabs, each slab having a generally flat horizontally extending configuration and having its vertical dimensions minor relative to its horizontal dimensions, at least one horizontally elongated girder means associated with each slab, a horizontally elongated receptacle in each slab in which is received one of the elongated girder means for distributing the weight of the slab, and a plurality of hanger means engaging each girder at spaced apart locations along the length of the girder and extending from the girder upwardly above the slab to means for supporting each hanger from above.