usace libby dam powerhouse roof replacement

The location of the work area for this $1M project has several unique challenges, including the proximity to high-voltage electrical distribution equipment and power lines, the limited access for hoisting equipment, and the proximity to the Kootenai River directly below.

The Libby Dam Powerhouse roof consists of 9 separate bays, each approximately 4,700 SF, and an additional 4 lean-to roof areas, each approximately 500 SF. The Libby Dam Powerhouse Roof Replacement includes the removal of the existing roof membrane; inspection, removal, and replacement of rigid insulation materials that have been water damaged; and installation of a new fully adhered 90 mil EPDM roof membrane.

The scope of the project also includes some life safety improvements that will become permanent additions to the building. We will provide an aluminum guardrail and ladder system along the lower edge of the roof bays and on the lean-to roof areas. The clear anodized finish designed for this railing requires that longer sections be detailed with mechanical connections that allow the system to be installed without the need for field welding. Our team will also install a new horizontal lifeline fall protection system along the downstream edge of the roof area.