Prefab Metal Chimney Housing Restoration

This home had an older-style prefab metal chimney housing designed with fin-style metal termination pieces rather than a conventional protective chimney cap. The top remained largely open and exposed to weather and animals, and the homeowner had experienced birds getting into the chimney area.

The metal housing was weathered and showed rust and coating failure, especially around the upper perimeter and lower areas near the roofline. The homeowner had received recommendations to replace the entire housing, a much larger and more expensive project that could involve removing shingles, pulling out the existing assembly, and replacing portions of the venting and housing.

After evaluating the existing structure, we determined that complete replacement was not necessary. The original metal housing could be preserved and restored. We treated the deteriorated metal, prepared and refinished the housing, addressed the flashing area, and installed a custom stainless steel cap to provide proper coverage while keeping the existing prefab assembly in place.

• Older-style prefab metal chimney housing with an open fin-style termination
• No conventional full-coverage chimney cap protecting the top opening
• Bird and animal access through the exposed termination area
• Rust and corrosion around portions of the upper metal housing
• Peeling and failing exterior coating on the metal surfaces
• Deterioration around the lower portion of the housing near the roofline
• Existing housing remained serviceable and did not require complete removal and replacement

Replacing this type of older prefab housing can become a major project because the assembly is integrated into the roof and venting system. Depending on the installation, full replacement can require disturbing shingles, removing the existing housing, modifying or replacing vent components, and installing a new exterior assembly.

In this case, the housing itself was still structurally serviceable. Rather than removing a usable assembly, the project focused on correcting the exposed and deteriorated exterior components. This allowed the homeowner to keep the existing prefab chimney while avoiding the cost and disruption of a complete replacement.

• Cleaned and prepared the existing metal housing
• Removed and treated rusted and deteriorated surface areas
• Prepared failing coating and exposed metal for refinishing
• Applied appropriate primer to prepared metal surfaces
• Repainted the housing to restore a uniform protective exterior finish
• Addressed the flashing area around the base of the housing
• Installed a new custom stainless steel chimney cap over the existing termination

The original fin-style termination left large areas open and did not provide the same type of coverage as a full chimney cap. A custom stainless steel cap was installed over the termination to create a more protected top assembly while maintaining the required open ventilation around the prefab system.

The new cap also helps prevent birds and larger debris from entering through the previously exposed top area.

The completed project preserved the original prefab metal chimney housing while dramatically improving its exterior condition and protection. Instead of replacing the entire housing, the existing metal was restored, rusted areas were treated, the housing was primed and repainted, the flashing area was addressed, and a custom stainless steel cap was added.

The result is a cleaner, protected, and more complete chimney termination without the unnecessary expense of removing a serviceable prefab housing.

• The existing metal housing is weathered or rusted but remains structurally serviceable
• Paint or protective coatings are peeling or failing
• The original termination is open or lacks adequate animal protection
• Localized deterioration can be treated without replacing the entire housing
• The homeowner has been quoted for full replacement but the existing assembly may still be restorable