Henry® Delivers Integrated Waterproofing System for Historic Federal Reserve Campus Overhaul
Henry® Delivers Integrated Waterproofing System for Historic Federal Reserve Campus Overhaul
Project Details
Location: Washington, D.C.
Owner: Board of Governors of the Federal Reserve System
Architect: Fortus, joint venture of CRTKL and Quinn Evans
General Contractor: Joint venture of Balfour Beaty and Gilbane
Waterproofing Contractor: Prospect Waterproofing Company
Consultant: SG&H
Henry Products Used
Modernizing a Legacy
The Federal Reserve Board’s renovation of the Marriner S. Eccles and FRB-East Buildings began in 2021 and is scheduled for completion in 2027. This long-term modernization project updates two historic structures dating to the 1930s.
Designed in the streamlined classical style by Paul Philippe Cret and Jules Henri de Sibour, the buildings occupy a prominent position on Constitution Avenue. The project brings both into compliance with modern standards for energy efficiency, seismic performance, physical security, and building technology—while preserving their civic scale and historical character.
Waterproofing work began in February 2024, with Prospect Waterproofing Company leading the installation of a multi-product system specified by the design team. Henry® products were chosen or their compatibility, ease of sequencing, strong performance history on government and institutional projects, and the availability of a comprehensive long-term warranty. When complete, the project will bring both buildings into compliance with modern standards for energy efficiency, seismic performance, physical security, and building technology—while preserving their civic scale and historical character.
Scope
- Below-grade waterproofing up to 40 feet deep
- Multi-level underground parking and tunnel
- Atrium additions and skylight reconstruction
- Restoration of historic façade and interiors
- Henry ULTRA Warranty
Challenging Conditions Below Grade
The site’s location on the National Mall came with clear below-grade waterproofing challenges. Beneath the buildings, tight clearances and aging infrastructure created complex site conditions. Excavation extended as deep as 40 feet below grade,revealing inconsistent substrate conditions, legacy footings, and unexpected groundwater activity. At FRB-East, construction included three new levels of underground parking beneath the historic terrace, as well as a new tunnel under 20th Street linking the two buildings.
Based on past experience, Prospect was confident that Henry® products could accommodate slab movement, maintain watertight integrity at irregular interfaces, and deliver redundancy across the below-grade envelope.
“The biggest challenge was sequencing the work under active demolition and excavation,” said Jim Stamer, President at Prospect Waterproofing, a specialty waterproofing contractor based in the Washington, D.C. area. “We were often installing in tight spaces, under existing slabs, or right behind excavation crews. There was no room for error."
Installation Details
Installation began from the ground up—literally. Depending on site conditions, crews first prepared either compacted soil or mud slabs before applying MiraCLAY® GM, a bentonite geotextile selected for its ability to self-seal and resistance to hydrostatic pressure. Serving as the base layer of the waterproofing system, MiraCLAY® GM was followed by the application of Blueskin® PreSeal® 435. Together, these products formed a robust dual-layer waterproofing defense beneath the slab.
Foundation walls were protected with MiraDRI®860/861, an SBS-modified bitumen sheet membrane installed using a cold-applied adhesive valued for its toughness and superior resistance to water infiltration. A double layer of MiraDRI® 860/861 was applied at vertical footings, pile caps, and elevation transitions for enhanced durability. To ensure system redundancy, all vertical and horizontal seams of Blueskin® PreSeal® 435 were carefully lapped and taped.
As an additional safeguard, Prospect Waterproofing installed MiraSTOP® BW and MiraSTOP® IW, an injectable waterstop system providing tertiary water protection.
Above grade, in parking troughs and expansion joints, Pumadeq™ Flex 31MV delivered a durable, fast-curing solution. Its combination of abrasion resistance and flexibility made it ideal for traffic-bearing surfaces requiring quick return to service and long-term waterproofing performance.
"This is the kind of job where waterproofing can't be an afterthought. It has to perform the first time - and for a long time to come."
A Civic Standard Reaffirmed
Once complete, the renewed Eccles and FRB-East Buildings will serve more than 1,750 employees and consolidate operations from leased space across the city. The improvements reflect the Board’s values of transparency, stewardship, and long-term investment in public assets.