New York, NY
Top of the Woolworth building, was once the tallest skyscraper until 1930, Manhattan, New York, America, USA

Project Description

Designed by renowned architect Cass Gilbert to be Frank W. Woolworth’s NYC headquarters, New York’s The Woolworth Building was completed in 1913 and stood as the world’s tallest building until 1930. Known as the “Cathedral of Commerce”, this Neo-Gothic façade is entirely constructed of decorative terra cotta and stands as one of New York’s most celebrated and iconic buildings. The Tower underwent a terra cotta restoration, decorative cresting replication, and a complete roofing replacement to transform the tower into luxury condominium residences known as The Woolworth Tower Residences.
As part of the project scope, it was determined that the roofs would be replaced due to their age and being impacted by planned alterations. The existing roofs were made of coal tar pitch and felts and dated from the late 1970s to early 1980s.

balcony of woolworth building NYC
Sikalastic detail on woolworth building in new york city
chapel detail of woolworth building new york city

Project Solution

Prior to commencing work on the roofs the concrete deck and masonry surfaces needed to be repaired. Sika concrete repair mortars and sealants were used to create a suitable surface to receive the new roofing system.

The Sikalastic® RoofPro membrane is a cold applied, fully reinforced, liquid applied roofing/waterproofing membrane. The Sikalastic® Roof Pro 25 system was installed on multiple roof terraces and setbacks in both a Protected Membrane Roof (PMR) assembly and Conventional Roof Assembly based upon the structure and designed use for each roof level totaling over 18,000 square feet. In order to meet the esthetic goals of the project, the Sikalastic® RoofPro membrane was manufactured in a terra cotta and copper patina color to closely match the existing building components. The color pigment is consistent throughout the entire thickness of the membrane and will not wear off like a top coat used to achieve color, thus ensuring long term aesthetics and performance. The completed roofs were finished with the Hanover Guardian® paver system and Ipe wood decking.

Project Participants

DEVELOPER: Alchemy Properties
CONSULTANT: Façade MD Architecture & Engineering
CONTRACTOR: Nicholson & Galloway, Inc.
PAVERS: Hanover Architectural Products