Hemispheric roofing

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In 1836, Methodists in Athens, Ala., bought a tract of land on Marion Street, one block from the town square. Soon afterward, a two-story brick building with a steeple visible from much of the city was erected. The structure is the second-oldest building in Alabama.

During the early 1920s, the church reached capacity, and a new church with a grand pipe organ was built nearby for $115,000. The first service in the present-day church was held March 19, 1925. The church has been renovated multiple times, and in 1997, a new bell tower was added.

After almost a century, the copper roof system on the dome reached the end of its service life, and in 2020, the dome and cupola were replaced by CopperWorks Corp., Decatur, Ala.

A new design

Production on the 700-square-foot hemispheric dome (a dome with a constant radius) began in October 2020. The original 23- by 10-foot dome was fabricated using diamond-shaped, flat, interlocking copper tiles.

The CopperWorks team erected scaffolding around the dome and removed the copper tiles and underlayment down to the original wood roof deck.

“The dome was one of the best structural frameworks I have ever seen,” says Daniel Delle, vice president and project manager for CopperWorks. “I have worked on many historical buildings, and this dome was solid and sturdy.”

The church was built in a historical district in downtown Athens, so dome renovations had to include historically accurate materials. However, a new design by Delle called for 3D copper tiles fabricated in different shapes to provide a modern appearance.

Wide squares, diamonds and other specially shaped profiles were incorporated. Half-square panels were used for the first row at the dome’s base. The widths and lengths of panels changed with each subsequent row. Narrow, more acute-angled diamond shapes were fabricated for the final nine rows, forming a connection to the circular platform with the cupola. The diamond-shaped tiles provided an even, continuous pattern between the profiles.

To cover the dome, CopperWorks craftsmen fabricated 288 interlocking tiles from 0.7-mil-thick copper using traditional Rauten methods that have been used for more than 200 years.

“The tiles’ spatial effect was created by working standing edges into the adjacent sides of the diamonds,” Delle explains. “These ridges were several millimeters high at the bottom tip of each diamond and reduced to zero on the opposite side. This technique raises the central axis and creates a harmoniously constructed 3D effect.”

In November, the CopperWorks team completed the hemispheric dome with a broad copper base and eight decorative brackets with floral motifs. More than 2,000 pounds of copper were used on the dome.

The cupola

The team returned in May 2021 to complete the cupola. The cupola’s shape was based on a full-scale drawing and the original tower’s design to replicate the tools needed for reproduction. The crown stands about 9 feet high and has a diameter of 6.89 inches with a thickness of .078 inches.

“The punching tools and drop mechanism were manufactured by our partners at Kaufmann Ulm Spenglereibedarf GmbH in Germany,” Delle says. “These cornice profiles were welded together to accessorize eight semiconical columns. The columns were soldered to the base and lacquered in white for historical accuracy.”

The sphere on top of the cupola was created as a detailed replica of a dismantled ornament and was fabricated in two halves.

“Maneuvering both halves was quite challenging because the number of assembled components, sizes and overall weight of the cupola kept changing,” Delle says. “The tower’s lower half was manufactured horizontally and erected to meet its other half. Once upright, the decorative and half brackets were assembled onto the tower’s lower portion, and the surrounding cornice was soldered to the connection profile.”

The team fabricated two substructures to hold the sphere’s weight. The first structure has the lower half of the tower, the columns and the cornice. The second structure stabilized the upper half of the cupola and the cross.

CopperWorks coppersmiths constructed an eyelet at the top of the crown so it could be lifted via crane onto the church after it arrived on-site.

Preserving history

Before lifting the crown onto the church, a time capsule containing documents and artifacts was included at the pocket of the base for a future generation to find.

“I was honored to design the dome,” Delle says. “The church still has a traditional feel to its appearance while showcasing a modern style. It is a pleasure to look at whenever I drive by.”

For its work on Athens First United Methodist Church, CopperWorks received a 2022 North American Copper in Architecture Award from the Copper Development Association.

CHRYSTINE ELLE HANUS is Professional Roofing’s associate editor and an NRCA director of communications.