Washington, DC

Georgetown University, Dahlgren Chapel


Dahlgren Chapel of the Sacred Heart, dedicated in 1893, is one of the campus’s iconic structures. The brick masonry building, with a below-grade crypt and program space, suffered from water infiltration and experienced structural damage caused by foundation settlement. As part of a comprehensive rehabilitation effort, SGH investigated leakage and designed below-grade waterproofing repairs.

SGH assisted Martin J. Reddy Architects, the designer of record, and Geier Brown Renfro Architects, the lead designer, with designing and selecting waterproofing systems for below-grade foundation walls. We worked closely with the design team to minimize the repairs’ appearance and achieve a robust yet sympathetic solution to address chronic leakage. Highlights of our work include the following:

  • Reviewed existing conditions, the proposed foundation underpinning and stabilization design, and related rehabilitation work
  • Prepared drawings and specifications for below-grade waterproofing
  • Advised the design team about component reliability and durability related to the waterproofing work
  • Developed waterproofing system details at the limestone water table and at similar exposed at-grade conditions


We also provided construction phase services, including the following:

  • Reviewed shop drawings and submittals for below-grade waterproofing, related foundation repairs, surface preparation and parge coating, and limestone water table anchorage
  • Visited the site to observe ongoing construction to compare with the contract documents and tracked action items
  • Responded to contractor requests for information related to the below-grade waterproofing
  • Collaborated with the university and contractor to develop practical solutions for unforeseen conditions encountered during construction

Project Summary



Completion Date




Construction Value
Repair & Rehabilitation | Preservation
Building Enclosures | Structures
Martin J. Reddy Architects
Specialized Capabilities
Geotechnical | Condition Assessments | Preservation | Roofing & Waterproofing

Key team members

Bradford Carpenter
Bradford Carpenter
Senior Principal
Niklas Vigener
Niklas Vigener
Chief Technical Officer