Portfolio: Project Details
Building 680 Reroof
U.S. Navy
Mare Island, CA
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When this twenty-two year old built-up roofing system began to fail in 1991, the
Navy decided to replace all 226 of Building 680’s 226,000 square foot roof.
Constructed in 1993 to house an assembly line for submarines, the design was
typical of industrial structures of this period; effective day lighting of the
interior workspace was essential. In order to achieve that goal, the main
horizontal plane of the roof was broken into 46 separate sub-roofs at five
primary levels. Each vertical drop between levels provided an opportunity to
install clerestory windows. The roof/clerestory arrangement used for this
building is referred to an “aiken” roof.
Specific challenges addressed in the design included:
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Building Expansion Joints: a manufactured building expansion joint cover system
(Expand-O-Flash) was selected to replace fabricated sheet metal components and
to provide continuity between horizontal and vertical lengths of the expansion
joint.
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Perimeter Flashing: the existing roofing system terminated at walls with
membrane flashing only. These had failed, and water penetrated the building.
Low parapet walls did not have copings. Our solution included installing
surface-mounted reglets with sheet metal counterflashing at walls, and sheet
metal copings at all parapet walls.
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Built-In Gutters: the original design included built-in gutters at the
uppermost roof that ran the length of the building and were in questionable
condition. These gutters were eliminated and replaced with conventional roof
drains and overflow drains. Crickets were installed at either side to direct
the water to the drain.
This project was awarded Second Place for a Large Roofing Project in the 1994
Document Competition sponsored by RCI (Roof Consultants Institute).
