Embassy of the United Kingdom of Great Britain and Northern Ireland
View the architectural study
Interpretive architectural study of the catalogued property.
3100 Massachusetts Avenue NW, Washington, DC
Eric Bedford’s office block wraps around an open court, with a circular conference pavilion beside the street.
| Fact | Value | Basis and sources |
|---|---|---|
| Constructed | 1960 | verified Design approved in 1955 and foundation stone laid in 1957. Bertram dates construction to 1958–1960 and the opening to 23 September 1960. |
| Acquired by the United Kingdom | 1941–1953 (site) | verified; Historic component plots acquired in 1941, 1951 and 1953; present lot 0064 is a later parcel consolidation. |
| Neighborhood | Observatory Circle | verified |
| Architect | Eric Bedford | verified |
| Rooms | 150–260 est. | estimated; Editorial range for the 138,980 sq ft office building: allow 55–65% enclosed usable room area and 350–500 sq ft per office/meeting/service room, rounded outward. The historical 550-person brief and subsequent open-office alterations make the range low confidence; workstations are not rooms. Estimated room total; a complete room inventory is unavailable. |
| Floor area | 139,000 sq ft | verified; LIVING_GBA, lot 2147/0064, building 1. Gross inventory area includes the registered chancery building complex; it is distinct from the smaller 2018 refurbishment scope. |
| Site area | 77,900 sq ft | verified; Parcel total: 2147/0064. DC ITSPE LANDAREA, recorded square feet. Roads and unrelated neighboring parcels excluded. |
| 2026 Value | $55.1M | verified; Parcel total: 2147/0064. Active 2026 DC ITSPE ASSESSMENT; land plus improvements. Not proposed value, tax owed, sale price or leasehold value. |
Scope and Evidence
Design approved in 1955 and foundation stone laid in 1957. Bertram dates construction to 1958–1960 and the opening to 23 September 1960.
Active delete code N; CY1YEAR and CY2YEAR are 2026; ASSESSMENT is the current total.
Approximate centre of the modern chancery roof outline in DC GIS. The official mailing address is 3100 Massachusetts Avenue NW; the tax parcel is addressed 3114.
Estimated room total; a complete room inventory is unavailable.
- gloverparkhistory.com
- maps2.dcgis.dc.gov
- maps2.dcgis.dc.gov
- maps2.dcgis.dc.gov
- maps2.dcgis.dc.gov
- roomfordiplomacy.com
- roomfordiplomacy.com
Research Questions
Where Is Embassy of the United Kingdom of Great Britain and Northern Ireland?
3100 Massachusetts Avenue NW, Washington, DC. Approximate centre of the modern chancery roof outline in DC GIS. The official mailing address is 3100 Massachusetts Avenue NW; the tax parcel is addressed 3114.
When Was Embassy of the United Kingdom of Great Britain and Northern Ireland Built?
Constructed: 1960. Record status: verified. Design approved in 1955 and foundation stone laid in 1957. Bertram dates construction to 1958–1960 and the opening to 23 September 1960. Verified in the record on 2026-10-21.
Who Designed Embassy of the United Kingdom of Great Britain and Northern Ireland?
Architect: Eric Bedford. Record status: verified. Verified in the record on 2026-10-21.
What Is the Floor Area of Embassy of the United Kingdom of Great Britain and Northern Ireland?
Floor area: 139,000 sq ft. Record status: verified. LIVING_GBA, lot 2147/0064, building 1. Gross inventory area includes the registered chancery building complex; it is distinct from the smaller 2018 refurbishment scope. Verified in the record on 2026-10-24.
What Is the Site Area of Embassy of the United Kingdom of Great Britain and Northern Ireland?
Site area: 77,900 sq ft. Record status: verified. Parcel total: 2147/0064. DC ITSPE LANDAREA, recorded square feet. Roads and unrelated neighboring parcels excluded. Verified in the record on 2026-10-24.
What Is the 2026 Value of Embassy of the United Kingdom of Great Britain and Northern Ireland?
2026 Value: $55.1M. Record status: verified. Parcel total: 2147/0064. Active 2026 DC ITSPE ASSESSMENT; land plus improvements. Not proposed value, tax owed, sale price or leasehold value. This is a tax assessment, not a verified sale price or market valuation. Verified in the record on 2026-10-24.