Mancini Mills Hayward

The Challenge

After approximately 30 years of service, the modified bitumen roof system at the Mancini Mills Building in Hayward, California had reached the end of its functional life. Worn seams, accumulated repairs, and general membrane degradation had left the roof vulnerable to moisture infiltration — a critical concern for a large-footprint warehouse property where water intrusion could impact stored goods, equipment, and building operations.

The building owner needed a durable, long-term roofing solution that would eliminate ongoing maintenance costs and restore full waterproofing performance across 56,520 square feet. Equally important was minimizing disruption to the businesses operating within the building throughout the construction process. Budget discipline was a core requirement: the project needed to deliver maximum performance and value without unnecessary expenditure.

Our Solution

After a thorough assessment of the existing roof condition and the building owner’s priorities, Fidelity Roof Company recommended a Duro-Last® Duro-Fleece® 60 MIL PVC single-ply overlay as the most economical and highest-value solution available. Rather than a full tear-off and replacement — which would have significantly increased both cost and project duration — the overlay approach allowed the new PVC membrane system to be installed directly over the existing modified bitumen substrate, eliminating costly tear-off and disposal fees while delivering a fully warranted, high-performance roof.

The Duro-Fleece® membrane was selected for its unique combination of a proprietary PVC thermoplastic top layer and a high-quality fleece backing on the underside — making it ideally suited for direct mechanical attachment over aged modified bitumen substrates. The 60 MIL thickness provides an exceptional top performance layer that resists UV radiation, fire, chemical exposure, and puncture, offering long-term durability critical for a high-traffic warehouse environment in California’s Bay Area climate.

Additionally, a single-ply PVC overlay installation is significantly quieter and less invasive than a tear-off, allowing the tenants and businesses within the Mancini Mills Building to continue day-to-day operations uninterrupted throughout the five-week construction window.

Project Execution

Fidelity Roof Company’s crew conducted a detailed pre-installation review of the existing 30-year-old modified bitumen system, identifying all areas of deterioration, existing repairs, and substrate conditions to ensure proper preparation for the PVC overlay system.

All existing repair areas and problematic sections of the modified bitumen roof were addressed prior to membrane installation to provide a uniform, stable substrate for mechanical attachment of the Duro-Fleece® membrane. A 4-person crew completed the full overlay installation across 56,520 square feet over a five-week schedule.

Upon project completion, the installation was documented and submitted for Duro-Last’s 15-Year No-Dollar-Limit (NDL) Warranty, which provides the building owner with full coverage against manufacturing and installation defects — backed by both the manufacturer and Fidelity Roof Company’s own 5-Year Workmanship Guarantee.

The Results

The installation of the Duro-Fleece® 60 MIL PVC system delivered complete waterproofing restoration for the entire warehouse roof, and the overlay approach and disciplined crew scheduling ensured that the businesses operating within the Mancini Mills Building experienced no interruption to their daily operations.

Due to rigorous project management, efficient crew deployment, and the inherent cost advantages of the overlay approach versus a full tear-off, Fidelity Roof was able to complete the project $70,000 under the forecasted budget, exceeding the client’s expectations.

By exceeding the client’s expectations both on performance and budget, Fidelity Roof Company further cemented a long-term relationship grounded in trust, effective communication, and consistently high-quality workmanship.