United Nations Secretariat

Originally constructed in 1952, the United Nations Secretariat Building serves as the administrative heart of the UN and houses offices for ambassadors and delegates from around the world. Larson Engineering, Inc. was honored to provide our engineering expertise for a full façade retrofit of this iconic structure—modernizing its appearance while meeting today’s stringent blast protection requirements.

As part of the retrofit, Larson tackled the unique challenge of analyzing and engineering state-of-the-art blast-resistant revolving and swing entry doors. Our team applied advanced structural modeling and engineering to provide seamless integration with the building’s architectural legacy.