The roof of the Century Square high-rise in Seattle, WA is made up of three semi-domes. The top semi-dome runs the complete length of the building, the second semi-dome is a quarter dome for much of its length, and the third semi-dome protrudes 20’ to 30’ from the face of the building at a much lower floor. Workers were exposed to fall hazards in excess of 300’ during window washing activities, and the existing procedures and equipment did not instill confidence or allow for 100% fall protection.

Century Square Building Downtown Seattle WA
Century Square Building Downtown Seattle WA


The management company in charge of building maintenance, though knowledgeable of the issues with the existing system, was unaware of legislation and regulations applicable to fall hazards. The arched ladders on the semi domes transfer from a vertical to a horizontal orientation. There are very few fall arrest systems that can lock off on an incline over 15 degrees and still function in both a vertical and horizontal application.


Gravitec educated the building maintenance department on the existing problems by providing them with a report and an oral presentation, which included a number of solutions and the pros and cons of each to afford the customer the ability to make an informed decision. Non-destructive testing was performed on the building to ensure sufficient strength to support the proposed systems. Gravitec integrated a number of fall arrest systems and equipment into the design that allowed for seamless movement from one system to the next. The building maintenance department was educated on the new system and fall protection equipment, as well as provided with a thorough user guide for future reference and new employee training.


The management company had been having poor luck finding a fall protection engineering firm that could provide them with viable options that addressed all their needs. Other engineering and fall protection companies were given the opportunity to provide solutions for the hazards presented, but only Gravitec provided a compliant, cost-effective and user-friendly system that directly addressed the needs of the project. Only Gravitec could provide the turn key product that included physical verification testing of anchors, design, supply, installation, documentations and training.