It encompasses a collection of architecturally distinctive row houses that were built between 1889 and 1892 by a single developer, and represent a unique early success in condominium ownership.

[1] The Beaconsfield Terraces are roughly centered on the junction of Tappan Street and Garrison Road, a short way west of Brookline's Washington Square.

These buildings feature steeply-pitched roofs, round-arch entranceways, corbelled brickwork decoration, gabled wall dormers, and polygonal window bays.

The last two buildings are Georgian Revival, with red brick exterior and entrance porticoes with Corinthian columns.

Knapp was financially overextended by the development, and eventually sold his interest back to Whitney.