O’Brien Upper Envelope

Public Buildings Service, is seeking to replace approximately 17,225 sf of existing roofing systems at the Leo O’Brien Federal Building (127 ft x 157 ft) will be replaced with new roofing systems with a new fully adhered TPO membrane roofing system comprised of torch down vapor barrier, multiple layers of Type VI Extruded Polystyrene (XPS) insulation, cover board, and eighty (80) mil TPO membrane; fire rated pressure treated wood will be used to add curbing and or curbing height as depicted within project documents; existing roof drains will receive new inserts and strainers; all drains will be confirmed as being clear and free any obstruction prior to completion; the existing roof has been identified to contain asbestos containing material (ACM) in specific areas as identified with project documents will be abated as part of project; new OSHA-complaint guardrails will be installed around the perimeter; a roof tie-off system (anchor points) will be installed and pull rating verified; and new lightening protection system installed and certified as functioning and operational. At the conclusion of the project, the existing site will be restored to its original condition. As part of the verification process to confirm proper installation the roofing system’s technical representative must conduct periodic inspection during the course of the installation, conduct a final inspection to verify TPO seam and roof terminations integrity. Option Work: Furnish all material, equipment, labor and supervision to perform the following work which includes but is not limited to: removing the existing roof pavers and installing a monolith roof under the cooling towers; reinstalling the previously removed pavers ensure all damaged pavers are replaced with new; removing and replacing the narrow band of roof surrounding the building at this level (10th floor); existing roof drains will receive new inserts and strainers; all drains will be confirmed as being clear and free of any obstruction prior to completion; remove one (1) door and frame, sealing up the opening by toothing in new masonry concrete block; and sealing the mason walls surrounding the cooling tower area (three sides) by applying two (2) coats of Dow-Corning Silicone coating. Base Bid Work includes but is not limited to the following work: approximately 17,225 sf of existing roofing systems at the Leo O’Brien Federal Building (127 ft x 157 ft) will be replaced with new roofing systems with a new fully adhered TPO membrane roofing system comprised of torch down vapor barrier, multiple layers of Type VI Extruded Polystyrene (XPS) insulation (amount of insulation required will create a height of approximately 4.5 inches), cover board, and eighty (80) mil TPO membrane; fire rated pressure treated wood will be used to add curbing and or curbing height as depicted within project documents; existing roof drains will receive new inserts and strainers; all drains will be confirmed as being clear and free any obstruction prior to completion; the existing roof has been identified to contain asbestos containing material (ACM) in specific areas as identified with project documents will be abated as part of project; new OSHA-complaint guardrails will be installed around the perimeter; a roof tie-off system (anchor points) will be installed and pull rating verified; and new lightning protection system installed and certified as functioning and operational. At the conclusion of the project, the existing site will be restored to its original condition. As part of the verification process to confirm proper installation the roofing system’s technical representative must conduct periodic inspection during the course of the installation, conduct a final inspection to verify TPO seam and roof terminations integrity. Additionally within one year of the date of substantial completion at a time mutually agreement upon by GSA and contractor the contractor as part of their contract shall perform an infrared scan of all the roofing areas using an independent third party. The scan results shall be sent directly to GSA with copy going to contractor. Contractor shall resolve any concerns identified. Contractor shall provide GSA with labor and material warranty in accordance with project documents. Alternative Base Bid Work includes performing ALL of the work outlined within the base bid scope of work EXCEPT that the amount of insulation to be installed will instead create a height of 6.5 inches and that a raised roof area will be created under each of the four (4) cell tower areas. The creation of this new raised roof area around the cell tower footprint is being required to facilitate the installation of the increase amount of insulation around the cell tower structures. The roof assembly remains relatively unchanged for wood substrate a stick down membrane is required such as Grace Ice and Water and or a similar type material. The approach required to install the TPO on this newly created raised area will be the same as that for the elevator penthouse roof area. The newly created raised roof under the cell towers will require walkway mats to be installed in that area to provide safe walk areas when working on and around the cell towers. Option Work (option work applies regardless of whether base or alternative is selected): Furnish all material, equipment, labor and supervision to perform the following work which includes but is not limited to: removing the existing roof pavers and installing a monolith roof under the cooling towers; reinstalling the previously removed pavers ensure all damaged pavers are replaced with new; removing and replacing the narrow band of roof surrounding the building at this level (10th floor); existing roof drains will receive new inserts and strainers; all drains will be confirmed as being clear and free of any obstruction prior to completion; remove one (1) door and frame, sealing up the opening by toothing in new masonry concrete block; and sealing the mason walls surrounding the cooling tower area (three sides) by applying two (2) coats of Dow-Corning Silicone coating. Additionally within one (1) year of the date of substantial completion, at a time mutually agreed upon by GSA and contractor, the contractor (as part of their contract) shall perform an infrared scan of all roofing areas using an independent third party. The scan results shall be sent directly to GSA with copy going to contractor. Contractor shall resolve any concerns identified. Contractor shall provide GSA with full labor and material warranty in accordance with project documents.

Division 07 -

Thermal and Moisture Protection, Dampproofing and Waterproofing, Thermal Protection.