Metal Roofing Engineered for a Covered Bridge
Reading Time: 6 mins
Last Updated: August 3, 2026 Published: July 16, 2026
Overview
Ohio’s Spellacy Covered Bridge, a $9.5 million replacement for a deteriorated iron structure, became Holmes County’s largest-ever infrastructure project upon completion in 2023.
Needs
The 300-foot timber-frame bridge needed roofing that matched its historic look while staying lightweight and flexible for the center crown, thermal movement, and traffic loads.
Impact
Now a landmark on the Wally Road Scenic Byway, the bridge has won praise from residents and visitors, plus two Engineering News-Record awards in the small project category.
Benefits
A Country Manor Shake system gave the bridge a natural wood-shake look at under half a pound per square foot, with flexible panels that helped finish the project four days early.
Completed in 2023, Ohio’s Spellacy Covered Bridge spans the Mohican River in Holmes County, replacing an aging iron bridge that had served the community for just 30 years. At $9.5 million, the project stands as the largest infrastructure undertaking in the county’s history — and one of the most visible. Located along the Wally Road Scenic Byway, which runs from northern Ashland County to southern Knox County, the bridge sits amid scenic campgrounds in a region known for its Amish heritage and historic character.
The bridge was named for engineer Matthew Spellacy, who originally built the road on the alignment of a former railway. Holmes County Engineer Chris Young, who has led the county’s engineering department since 2003, oversaw the project as a multi-year labor of love for his team. Since completion, the bridge has earned two Engineering News-Record awards — the National Best of the Best and the Midwest Best Project, both in the small project category — recognition that reflects both the technical execution and the community pride the structure has generated.
Design Requirements
The replacement structure needed to satisfy two competing demands: durability that would outlast its 30-year predecessor, and an aesthetic that honored the historic character of the surrounding Amish community. A team of professionals came together to work with Holmes County (Owner) and the Ohio Department of Transportation to meet these objectives:
- Palmer Engineering – Lead Design Firm
- Kokosing Construction Co. – General Contractor
- OHM Advisors – Civil Engineer
- Smolen Engineering – Structural Engineer
The team’s solution was a covered bridge built from rough-sawn southern pine and glulam timbers, spanning 300 feet across two lanes at 24 feet wide.
That timber-frame approach placed specific and unusual demands on the roofing system. It needed to:
- Match the architectural intent — a natural, traditional wood-shake appearance consistent with the historic covered-bridge form
- Minimize dead load on a long-span timber structure
- Accommodate structural movement, including the bridge’s engineered center crown, thermal expansion and contraction, and the flexing associated with ongoing two-lane traffic loads
Few roofing systems are built to flex with a structure the way this project required — most are designed for static substrates. That constraint shaped the entire roofing selection.
The Solution
The design and engineering team specified Isaiah Industries’ Country Manor Shake roofing system. At under half a pound per square foot, the panels added negligible dead load to the timber trusses — a critical factor given that each of the bridge’s four primary trusses already weighed 168,000 pounds on their own.
Two features of the panel system directly addressed the structural movement requirements:
- Interlocking 12″ x 48″ panels provided enough flexibility across the roof plane to move with the structure rather than resist it.
- Hidden fasteners driven through an accordion-pleated fastening flange isolated the fastening points from movement stress — the pleated flange absorbs structural flexing before it can transfer load to the fasteners themselves.
This decoupling of fastener and structural movement was central to the roof’s long-term performance: a rigid attachment method in this application would have risked fatigue failure or panel distortion as the bridge crowned, expanded, and flexed under traffic and seasonal temperature swings.
The panels were finished in Pearl Black with a Kynar 500 PVDF coating using cool pigment technology, producing an aged wood-shake appearance while managing solar heat gain on the pitched roof surface.
Construction
General contractor Kokosing Construction built the bridge in two primary sections, each craned into place atop purpose-built pilings — a sequencing decision driven by the structure’s scale and the site conditions along the Mohican River. The project team worked against a 365-day completion goal from the outset.
Structurally, the bridge was engineered with a pronounced center crown so the deck would not sag over time under the combined weight of asphalt paving, two lanes of traffic, and snow load on the roof — a design consideration that fed directly back into the roofing system’s need for in-plane flexibility.
The Country Manor Shake system was installed as one of the final steps in construction. Its ease of installation — a function of the interlocking panel design — helped keep the project on schedule; the bridge was completed four days ahead of the 365-day goal.
Results
The completed Spellacy Bridge delivers on both fronts the project set out to solve: a roofing system light and flexible enough to perform on a moving timber structure, and an appearance that reads as authentic hand-split wood shake rather than metal. The outcome has been validated both by industry recognition — two ENR Best of the Best honors — and by public reception in Holmes County.
“Residents are proud of it, and the visitors are amazed at how beautiful it is.“
Holmes County Engineer Chris Young
For architects and engineers evaluating roofing on long-span timber or other structures subject to ongoing movement, the Spellacy Bridge demonstrates a proven approach: a lightweight interlocking panel system with an isolated, flexible fastening method can meet demanding structural performance criteria without compromising a historically accurate architectural aesthetic.
The Spellacy Bridge demonstrates what’s possible when metal roofing is engineered to meet real structural demands — light weight, flexibility, and lasting performance — without compromising a project’s architectural intent. Isaiah Industries’ complete line of metal roofing products offers solutions for projects far beyond the conventional, from historic restorations to structures with unique movement, load, or design requirements.
Ready to explore the right roofing solution for your next project?
Visit IsaiahIndustries.com to review our full range of metal roofing systems, products, and services. We invite you to contact us via email or speak with our customer service team about how these solutions can be adapted to your project’s specific needs.
Sources
- All images courtesy of the Ohio Department of Transportation and used with permission.
- Ohio Magazine March/April 2025
- OHM Advisors Website: Project Page July 2027
