Interface Engineering Selected for The Octagon House Modernization

Interface Engineering has been selected by the Architects Foundation to support the sensitive modernization of The Octagon House, a 9,000‑square‑foot National Historic Landmark in Washington, DC. Designed in 1799 by Dr. William Thornton, architect of the U.S. Capitol, The Octagon began as a private residence before serving as the temporary White House following the War of 1812. Over time, it functioned as a school, government offices, and tenement housing. Today, The Octagon highlights the enduring relationship between architecture, civic purpose, sustainability, and social equity.

The Federal‑period masonry building is undergoing a comprehensive evaluation and upgrade of its mechanical, electrical, plumbing, and fire protection systems to better support its use as a historic museum while preserving its architectural character. The project centers on a full HVAC overhaul designed to reduce energy use while introducing a high‑performance system appropriate for a landmark structure with single‑pane windows and significant historic detailing.

Interface’s scope includes MEPfP engineering services to assess existing conditions, develop a system upgrade strategy, and support performance‑based planning aligned with the project’s sustainability goals. The work will prioritize durable, maintainable, and energy‑efficient solutions that minimize impacts to historic fabric and support the Foundation’s goal of achieving LEED® Certified status. Optional energy modeling services will evaluate system performance and feasibility relative to LEED objectives.

All recommendations will balance modern building performance, accessibility, and long‑term operational needs with preservation requirements for this nationally significant historic resource.