URIS Library and McGraw Tower Envelope Renewal at Cornell University, Lead Roofing

McGraw Tower is a 173-foot clock tower originally constructed as part of Cornell University’s historic library. Completed in 1891, it is one of the university’s most iconic landmarks. The tower’s roof was originally made of Spanish tile, but in 1932 it was replaced with a lead-coated copper chevron roof. Over the decades, the roof was patched repeatedly, yet persistent leaks continued to threaten the structure. After more than 130 years, it had reached the end of its service life.

Because the chevron-patterned roof had become a character-defining feature of the building, the Design Team on the project approved a full replacement in kind using sheet lead instead of reusing lead coated copper. Lead is a material well-suited for both historical accuracy and long-term performance. Commonly used on historic buildings today, sheet lead does not pose any threat to the people or landscape below, as outlined in our blog post, "The Benefits of Sheet Lead Roof Cladding"

To support the material decision-making process, Heather & Little (H&L) worked closely with the Design Team during the early stages of the project, providing technical consultation and material expertise. We fabricated full-scale mock-ups of the proposed roofing assemblies, allowing the team to evaluate appearance, detailing, constructability, and long-term performance before finalizing the design. This collaborative approach helped confirm sheet lead as the most appropriate replacement material, ensuring the new roof would meet heritage requirements while delivering durability and performance suited to the tower’s demanding conditions.

In addition to consulting with the Design Team, H&L, as a subcontractor to Welliver, was entrusted with the complete fabrication and installation of the new 6lb sheet-lead roofing system, replicating the tower’s distinctive chevron batten-seam design with precision. Our scope included supplying and installing the lead panels, battens, stainless steel fasteners, copper cleats, synthetic and fabric underlayments, welded connections, and all associated flashing components. We also produced detailed shop drawings, mock-ups, and documentation of the existing conditions to ensure the restoration aligned faithfully with both heritage requirements and modern performance standards.

H&L’s work extended to the tower’s custom lead spire cap and eave assemblies, all fabricated and installed in accordance with rigorous heritage specifications. Using lead, we reproduced intricate profiles, seamless transitions, and watertight joints essential for long-term protection.

This project showcases H&L’s unmatched expertise in traditional leadwork, complex historical replication, and the delivery of finely crafted architectural metalwork for some of North America’s most significant heritage structures:

• A.A. Heaps Building
• Legislative Assembly of Ontario