There were earlier Harrington Houses in London, located at Craig's Court, Charing Cross and at Stable Yard, St James's.

[2][3] Works were carried out under the supervision of Charles James Richardson, who was the surveyor to the Earl's South Kensington estate.

[3] Details and the final plans are thought to have been left to Richardson; he did, however, acknowledge the "great measure" the Earl was involved in the design.

[3] Richardson was not entirely complimentary of the Earl's contributions, pointing out that the flat outline of the building and low roofs were not usually part of the Gothic style.

[3] One particularly harsh criticism stated: "Were I to express my opinion of it without reserve, I should be compelled to make use of language and epithets which, however justly merited, would be deemed as illiberal as they would be disagreeable...

[3] The entrance hall lead to the saloon, at the centre of the house, which was two storeys high and topped by a skylight incorporating "embosed and coloured glass" featuring "shields, coats of arms, mottoes and monograms".

[3] The saloon led onto a large picture gallery at the back of the house, which was flanked either side by two drawing rooms, one of which gave access through to the conservatory.

[3] The basement was 14 feet tall and extended underneath the courtyard to the south of the house: this contained the kitchen, scullery, pastry-room, stillroom, dairy, wash-house, laundry, butler's pantry, steward's room, servants' hall, men's cellars, dust-pit and closets.

[2] The inscription "Harrington House" remained over the door until the Soviet Embassy took possession, at which time it was painted over and replaced with the number 13.

[3] These alterations including the demolition of the house's bell-turret, changing the windows of the conservatory, and replacing the original sloping roof with a flat one.