Refresh and Repair: Watergate South Co-op Board Tackles Balconies
The Watergate is a historic apartment complex with three luxury residential buildings located on the edge of Northwest Washington, DC.
Watergate South co-op building accounts for 257 luxury residences overlooking the Potomac River across its 14 stories. The Watergate complex's wraparound balconies and curving towers are one of its most distinctive features, some balconies extend as far as 129 feet providing panoramic views of the surrounding landmarks.
Since 2011, Kline Engineering has been retained by Watergate South as their structural engineering consultant on several projects. For one of our most recently finished ones, our team inspected every balcony on the 14-story Watergate South Building.
by Joseph DuBoisTHE PROJECT
As a rule, the Watergate South board and management prioritize a safe and pleasant environment for all its residents. Due to the natural deterioration of the building façade and balconies, Kline Engineering & Consulting (KLINE) was brought on to perform a comprehensive inspection as a part of Watergate South’s maintenance plan. Being experts in Post-Tensioning (PT), KLINE is aptly suited to evaluate structures such as this innovative PT complex built in 1971.
Inspection Results
This visual, non-invasive inspection was performed in May of 2019, covering both the structural and aesthetic conditions of the balconies. We gently sounded the concrete slabs and balustrades with hammers, searching for spalled or delaminated concrete. The balcony handrails and guardrails are secured to the concrete with anchor bolts – areas where cracking often occurs. Several of the unique concrete balustrades had cracked, allowing water to corrode the metal reinforcing bars inside, causing small chunks of concrete to come loose. KLINE also recorded signs of leaks or ponding of water to determine the condition of the drainage system. The more vulnerable areas higher in the building generally showed higher levels of deterioration than the lower areas.
At the same time, notes were taken on the state of the paint covering the slabs, railings, and façade frames. Though not structural, these coatings provide necessary protection to the concrete and metal substrates beneath. We then focused on the remaining features including balcony dividers and windows.
KLINE Senior Project Engineer Joseph DuBois records balcony structural and aesthetic conditions.
MOVING FORWARD
After facing many challenges due to the pandemic, Watergate South decided to move forward with the project and KLINE performed a follow-up inspection in March of 2022. This encompassed reviewing balconies with critical repairs and inspecting any that were not accessible in 2019. This enabled KLINE to determine the progression of deterioration between 2019 and 2022, which gave valuable insight into the necessity of the repairs.
With the findings of these two inspections, KLINE designed repairs for every single balcony, ranging from purely aesthetic and preventative to localized structural and drainage rehabilitation. A challenge in this repair design is preserving the historic appearance of the building for which mockup assemblies were mandated during the initial repair phase. This allows Watergate South to know exactly what the repairs will look like before commencing with the repairs on the entire building.
To minimize both time and cost – while prioritizing quality – KLINE conducted a competitive bidding process with reputable contractors in the area, most already familiar with the site. This gives the board and management the best possible outcome for this project.
Precast Balustrade Concrete Spall and Corrosion
Coating Deterioration of Concrete Slab Soffit
CONCLUSION
Over 50 years old, this iconic building with the then-innovative Post-Tensioned concrete design has stood the test of time. The board and management’s decision to proactively maintain the façade and balconies ensure the safety of the residents and the building’s structural integrity. With these repairs, Watergate South will continue to be a coveted residence for many years to come.
Joseph DuBois is a Senior Project Engineer on Kline Engineering & Consulting’s Team.
