1345 Avenue of the Americas, New York, NY

Main Roof and Penthouse Roof Replacement

The main roof and penthouse roof at 1345 Avenue of the Americas has long history of water infiltration, which consists of ineffective through wall flashing at the penthouse walls, failing penetration pockets at the low-lying window washing rig rail supports and aging membrane.  Careful probing, water testing and material research concluded that the most appropriate roofing system for the main roof would be an inverted roof membrane assembly with a reinforced, liquid membrane system on a modified bitumen membrane sheet because of poor substrate.

The liquid membrane system allowed for the proper flashing of the low termination post supports and provided a seamless waterproofing system for the poorly sloped deck. The roofing system was protected with insulation and gravel, with a precast paver walking surface for service personnel, especially window washing operations and equipment. The penthouse structure was roofed with a two ply, modified bitumen roofing system on tapered insulation on a vapor barrier. This system was required to provide the necessary positive slope to drains.

The elevator stair penthouse roof was completed many year later and consisted of two-ply modified bitumen membrane on tapered insulation with fabric reinforced liquid membrane.