SpecTips - Single-Source Overburden Warranties for Roof Garden and Plaza Systems

Avoid Unexpected Liability for Removal and Replacement of Overburden Materials

Rooftops were once a place that were rarely thought about, visited, or utilized. But with the extremely high cost and scarcity of land in urban environments, code bodies, building owners, and designers have begun to recognize and utilize this once forgotten space. Over the last several decades, green roofing and rooftop amenity space designs have been on the rise due to their environmental benefits and ability to maximize useable space while staying within the building’s footprint.

With the influx of overburden designs, it’s easy to overlook the question of who is responsible for removal and replacement of the overburden materials in the event of a leak.

Overburden warranties provide removal and replacement of overburden materials needed to access the roof in the event of a roof leak. However, not all overburden warranties are created equal. An overburden warranty provided by anyone other than the roof membrane manufacturer means almost nothing.

The meaningful differentiator for overburden warranties is whether or not they’re “single source”. Single-source overburden warranties are only available from roof membrane manufacturers and are the only way to know you’re truly covered if a leak occurs on overburden projects.

The good news is that most membrane manufacturers offer roof garden and amenity space products and systems that can meet almost any rooftop design and are compatible and warrantable together. When all materials, including the roofing and overburden materials, are purchased from and warranted by a single source, you avoid the finger-pointing, liability, and potential litigation that may arise from mixing materials from multiple sources.

To avoid unwanted and unexpected liability on overburden projects, ensure that your specifications require the installers to source the roofing materials, as well as all overburden materials, from a single source, and that a single-source overburden warranty is provided.

SPEC TIP - In MasterFormat Division 7 sections, Part I “General”, include the following:

• In section 1.5, “Quality Assurance”, include a requirement for “Overburden Source Limitation”:

-Obtain [roof garden] [plaza paver] assembly components and accessories from the roof membrane manufacturer.
-Overburden materials must be approved for use over membrane system and included in single-source overburden warranty from the roof membrane manufacturer.

• In section 1.7, “Warranty”, include verbiage requiring a single-source overburden warranty:

-Provide a [10][15][20] year single-source overburden warranty requiring that the roof manufacturer is responsible for any and all overburden removal and replacement needed for roof repair during the warranty period.

View Traditional Roof Garden Specification, Maintenance Guide, and Details here.

View the Roof Garden Overburden Warranty Sample here.