The property passed to Lucy Josephine Bagot who was most definitely a member of the colonial gentry, sometimes called the 'establishment'. She was a daughter of Sir Henry Ayers, a former premier and chief secretary, and in 1879 married John Bagot. Bagot, a grandson of Charles Hervey Bagot, was typically a pastoralist, a mining company director, director of the firm Bagot, Shakes and Lewis Limited and an MP.
The house at Pennington Terrace was purchased in 1909, about a year before John Bagot's death in 1910. Lucy Bagot lived there until 1920 when the house was bought by Dr Arthur Murray Cudmore. Cudmore enjoyed a similarly assured social position, due to his birth (his grandfather Daniel Henry Cudmore was a renowned pastoralist) and his own occupation as a leading surgeon of the times. Pennington Terrace was an ideal address, not only because of its prestigious location, but also because most of Cudmore's pursuits were located nearby. He lectured at the university, was consulting surgeon at the Royal Adelaide Hospital and was one of the syndicate which set up Ru Rua Private Hospital in North Adelaide (see Ru Rua Mansions).
Soon after he bought the house, additions were made on the eastern side which were in sympathy with its original character. Cudmore was knighted in 1945 and died in 1951. The house was sold in 1955 to the South Australian Institute of Teachers and in the 1960s a further addition was made to the east of the 1920 extensions, completing the present street frontage.
Erected of finely finished sandstone, the building is notable for its distinctive use of Venetian Gothic design elements and is a rare instance of the use of this style in residential design. The surrounds to openings on the original street frontage (to the west) are notable, the voussoirs having been carefully selected for their contrasting hues. String courses and drip moulds complement the stonework used in the street frontage. Sandstone rubble has been used in the construction of the side walls. The cast-iron balustrading, frieze, columns and spandrels are particularly fine and in original condition.