A roof fall occurred in 1 west bleeder at 84xc. Was approx. 8' H, 18' W and 25' L. Area was bolted with 8' point anchor resin assisted bolts, 12' CC cable bolts in pattern along with roof screen and bacon straps. Fall did not obstruct vent. or escapeways. Cause of fall was deterioration due to weathering. Floor/Roof support will be set as reported to prevent future occurrences.