Glass industry is one of the main consumers of refractory products in Russian Federation. The glass industry is energy-intensive sector of economy. Technical and economic indices of glass production are dependent on efficiency of operation of glass furnaces. Efficiency of operation of the furnace is determined by quality of refractory materials. Quality of silica refractories is dependent on content of alumina in them. High content of alumina leads to decrease in service life of the materials. Operation of thermally insulating roof has been considered. Conditions of efficient utilization of silica in roof and walls of the furnace have been discussed.