A roof fall was found at 2:55 am on South Mains ""B"" beltline at 7 x-cut. The belts went down around 2am and upon further investigation after trouble shooting the belt was walked. Cause of this roof fall was deterioration of existing roof. Area bolted with 8' bolts and resin with supplemental supports installed. Size of fall is approx. 25' long by 50 to 60' wide by 10' high.