To know if your ceiling needs replacing, consult an expert. If you notice cracks, water damage, bubbling, mold, or discoloration, call a pro immediately to prevent them from worsening. A pro will assess any damage to estimate ceiling repair costs. What looks like minor damage can be deceiving. Ceilings can conceal bigger problems and may go from sagging to collapsing without repairs or replacement. Repairs work for minor cosmetic damage, but extensive damage requires replacement.