Commercial Building’s Rusty Metal Roof Linked to High Zinc Levels in Nearby Creek

A storage facility, of approximately 5,000-square feet, at an industrial complex in Richmond, California had a metal roof of approximately 60 years old that was rusty. The rust was impacting more than the roof. A creek behind the building was tested by an environmental agency and found to have high levels of zinc, which was attributed to coming from the roof’s rainwater runoff.

Finding a Solution for a Rusted Industrial Metal Roof

The environmental agency directed the company to repair the roof. An executive from the industrial company recalled seeing the product, Retro-R® Panel, manufactured by Duro-Last/ Exceptional Metals, at a trade show.  We were contacted by the manufacturer’s local sales representative to help with the project.

Retro-R® Panel was determined to be a perfect solution. The metal roof did not have to be removed, because the Retro-R® Panels are designed to fit over an existing roof, thus eliminating what could become a disruptive, dangerous, and expensive project. The panels have a protective layer on the backside, which acts as a barrier that prevents the rust from spreading to the new panels.

Another issue that had to be addressed was the fact that there is an integral gutter connecting the storage facility to another building from which rain water deposited from, potentially impacting the creek.

Metal Roof Panel Overlay Process

The process to install the panels began by preparing the existing roof. It was scraped and cleaned of miscellaneous debris, followed by replacing existing skylights. Then, the panels were put on, as well as pre-fabricated flashing and trim. The only custom work involved installing roof curbs.  The integral gutter between the two buildings was then lined with new membrane.


All metal surfaces that rain water was running from were covered. Retro-R® Panels are easy to install, cost effective, have a great appearance (a choice of colors is offered for panels, gutters, and flashings), and are designed so that a job can be done fairly quickly. However, the roof’s condition, slope, and other factors, can impact time required.

For the industrial company’s storage facility, the new roof gives the facility an updated look and zinc levels in the creek have been greatly reduced. Adjacent buildings will soon require the panels, and plans are underway to move forward with the same scope of work as was performed on the storage facility.


5,000-square feet, at an industrial complex


Richmond, California

If your commercial roof is more than 20 years old, it may be time to replace it. Contact us to discuss your project.

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