Youghiogheny Resource Managers Building Siding Replacement

USACE, Pittsburgh District, has an upcoming requirement to replace the siding of the Resource Managers Office at Youghiogheny River Lake. The work described herein shall be performed at the Youghiogheny Resource Managers Office (RMO) building located within the Youghiogheny River Lake project area in Confluence, Pennsylvania. The building currently serves as administrative office space for the U.S. Army Corps of Engineers. The RMO building was constructed in 1986 and is a multi-level, timber-framed structure built into the hillside overlooking the impoundment side of the dam. The exterior walls consist of 2x6 wood stud framing with 6-inch fiberglass batt insulation (R-19, foil-faced). Interior partitions consist of 2x4 wood studs with 1/2-inch gypsum wallboard. The existing exterior wall assembly consists of 1/2-inch asphalt-saturated fibrous sheathing with 5/8-inch cedar-faced T1-11 plywood siding, for a combined nominal thickness of 1-1/8 inches. Exterior trim and fascia consist of various widths of cedar lumber. The building is supported by cast-in-place concrete footings and 12-inch concrete masonry unit (CMU) foundation walls. The rear wall section and balcony framing are supported by 4 feet-0 inches wide by 5 feet-0 inches deep concrete footings, laminated wood columns (8-3/4 inches x 15 feet-0 inches), and laminated wood beams (8-3/4 inches x 15 feet-0 inches).This project consists of the removal and replacement of the existing exterior wall cladding system. The Contractor shall remove and dispose of the existing T1-11 siding and 1/2-inch asphalt-saturated fibrous sheathing in their entirety. The Contractor shall furnish and install a new exterior wall assembly consisting of 1/2-inch APA-rated structural wood sheathing, a continuous weather-resistive barrier (WRB), 3/8-inch nominal preservative-treated wood furring strips, and 5/16-inch fiber cement lap siding in accordance with manufacturer requirements. The new wall assembly is intended to match the existing wall thickness (approximately 1-1/8 inches) to maintain alignment with existing window and door openings. Minor dimensional variation within normal construction tolerances are acceptable and shall not require modification or resetting of existing windows and doors. The Contractor shall not reset, relocate, or otherwise modify existing windows and doors. Furring strips shall be installed vertically over the WRB at a maximum spacing of 16 inches on center and shall be fastened through the sheathing into wall framing members. Fiber cement siding shall be installed horizontally over the furring strips and fastened through the furring and sheathing into wall framing members. Furring strips are intended to provide a drainage and ventilation cavity and shall not be used as the sole fastening substrate for the fiber cement lap siding. The Contractor shall ensure that all fiber cement lap siding edges are supported by framing members or approved blocking in accordance with manufacturer requirements. The Contractor shall furnish and install all required trim at windows, doors, corners, and transitions. Trim material shall be fiber cement. The cedar hand railing on the balconys is to be new capped PVC or capped composite decking of matching color to fiber cement board siding. The Contractor shall provide complete flashing at all required locations, including but not limited to head flashing at windows and doors, Z-flashing at horizontal joints and transitions, and kick-out flashing at roof-to-wall intersections. All flashing shall be integrated with the WRB in a shingle-lap manner to maintain a continuous drainage plane.