Johnson & Colgan Halls

WDP performed an existing conditions survey to document the roofs for replacement. During the survey, test cuts were made in the existing roofing systems to confirm existing materials and slopes. Water infiltration testing was performed at numerous locations on Johnson Hall to determine causes of the leakage and help with the replacement design. A new hybrid 4-ply roof system (3-ply BUR with reinforced modified bitumen cap sheet) was designed for the replacement on both buildings.

Existing fall protection equipment on Colgan Hall and the existing stair tower railing on Johnson Hall were load capacity tested. New fall protection accessories were added to both buildings. In addition to the roof replacement and fall protection design, the secondary overflow scuppers were added to Johnson Hall. The new roof system was designed to obtain a 20-year warranty at the completion of construction, with an option for a 30 year warranty alternate. WDP produced Contract Drawings and Specifications for bidding and submitted these as two separate design packages so that each building roof replacement could be performed on George Mason University’s preferred schedule. Construction administration services by WDP are planned for during construction.

• Roof System Replacement Design
• Diagnostic Water Testing
• Fall Protection Load Testing
• New Fall Protection Design
• Construction Administration