Historically, chase covers were predominantly constructed by builders. These covers were often fashioned on-site with minimal reinforcement, lacking a crossbreak, and primarily fabricated from sheet metal.
Chase covers can become problematic when they begin to corrode, permitting water ingress into the chimney chase. This corrosion can lead to irreparable damage to the fireboxes. If left unaddressed, the firebox may deteriorate to the point of requiring costly replacement, resulting in extensive repairs.
The chase cover can be likened to a snug-fitting shoebox lid when properly installed atop the chimney. Some individuals refer to it as Cala pan flashing, while others may call it a chimney cap.
Chase covers, or chase pans, occasionally feature a shroud—a decorative component that attaches to the pan. This shroud often comes equipped with legs to conceal the round termination cap within the chase cover.