Built on Telephone Avenue in 1903, Armada House was originally known as Avon House. It was designed by local architect, Henry Williams and was the head office of the Bristol Water Company and then later the British Telephone Exchange.

Some of the most notable features of the building are the 14^th century fireplace, bearing a Tudor rose and the Bristol coat of arms, in the lobby and the Jacobean-style 15^th century fireplace on the first floor. The latter was purchased from the Elton family, a Baronetcy who owned Clevedon Court.

In 1958, Telephone Avenue became somewhat well-known when the Queen placed the first non-operator call to Edinburgh.

The building was owned by BT from the 1970s to the 1990s, and around this time its name changed to Nova House. BT boasted of their unique video-conference service called Confravision.