Standing at 813 ft., this 60-story skyscraper in the Financial District of Manhattan opened in 1961 and served as the headquarters for Chase Bank for decades. The inverted flat roof assembly at the very top of the building consisted of a liquid-applied PMMA membrane with insulation and concrete paver overburden. The existing liquid membrane had started to fail and allow moisture to enter the building, sending the client on a search for a high quality option that would be the least disruptive and financially sensible.
From a logistical standpoint, major roofing work in Manhattan is as tough as it gets. The building is managed by CBRE and they chose to utilize Triton’s non-toxic, industrial-strength membrane that would be able to tenaciously adhere to the existing PMMA coating. This option would minimize disruption to their tenants and operations, maintain the benefits of a seamless, fully-adhered membrane, and keep costs in check.
The inverted roof, sometimes referred to as IRMA, consisted of a layer of drainage mat over the old membrane, a layer of loose-laid insulation boards, and a layer of concrete pavers on top of the insulation. The overburden was removed in sections to exposed the existing PMMA waterproofing membrane so that it could be cleaned and prepped for an application of the new TritoFlex 2K synthetic rubber membrane. The new TritoFlex 2K membrane was applied in one coat at 100 dry mils over the entire roof field and flashings, creating a new thick, durable, and flexible waterproofing membrane directly over the old PMMA. The contractor then replaced the insulation and pavers on top of the new membrane, avoiding astronomically higher costs that would have come with a conventional roof replacement. The new roof membrane came with a 20-Year NDL Material and Labor Renewable Warranty.