It was built in 1876 and brought into public use as the New Zealand Convalescent Hospital during the First World War.

In the interwar period Hornchurch was developed as a suburb and Grey Towers was demolished to be used for housing.

The gothic mansion was built in 1876 for Lieutenant-Colonel Henry Holmes, the owner of the Hornchurch Brewery.

From November 1914 it was used as a military depot, housing first the 23rd Royal Fusiliers and then the 26th Middlesex Regiment.

[2][3] In the interwar period Hornchurch developed as a suburb of London and land was required for house building.