Chimney Extensions

Cast Stone Institute 2016 MANUFACTURING EXCELLENCE Award Winner


This unique application of Cast Stone called for the fabrication of very ornate custom Cast Stone chimney extensions for a large private estate. This project consisted of fabricating (5) large decorative Cast Stone chimney extensions, incorporating (5) unique designs and shapes, to fit over the original chimneys.

The role of cast stone was to create stunning visual appeal by the incorporation of highly decorative chimney extension, intended to replicate old world architecture.

The Cast Stone chimney designs created significant mold fabrication and casting challenges. Each chimney had unique dimensions and radii, each with different architectural artwork on the exterior. The "through the wall" decorative patterns near the tops of the chimneys, ultimately serve as the outlet for the chimneys, while creating the striking architectural appearance. Incorporating all of the various architectural details into the relatively small mold space, proved to be a significant challenge.

The molding process was extremely complex, as each chimney had unique designs, and different radii, requiring a new mold for each chimney. The recessed architectural features required hundreds of individual elements to be handmade and custom shaped to fit the radius of the mold surface.

The largest challenge of the project was incorporating the unique architectural elements while meeting the overall functionality requirements of a chimney extension. The Cast Stone chimneys also have a solid one-piece cap, which prevents rain and snow from entering directly into the chimney flue.

100+ years ago, these type of elements would have been handcrafted onsite, many times out of individual bricks. The custom cast stone elements replicated this old-world architecture, and allowed the units to be installed very quickly onsite. The chimneys create not only stunning visual interest, but also serve the utility function of chimney extensions.

Comments from the Judges:
"Complexity is impressive and each one is different"

"Difficulty in design, production and installation"

"True to the style and supports the architect. Beautiful!"

"The chimney tops were so unique they made the mansion."

"The mold work was a manufacturing marvel. Such a difficult project done very well."

Additional Images: 
Chimney Extensions
Chimney Mold
Poured chimneys removed from molds.
Chimney Extensions