The Boarding House for Westminster School - the first stage in the process of rebuilding, begun on 23 April 1935 - was completed in time for the demolition of the properties on the Church House site to commence on 4 August 1936.
The Corporation's offices moved into 5a Dean's Yard and the church societies which had been tenants of the old House were transferred to Grand Buildings, Trafalgar Square. Many of the offices of the Church Assembly, meanwhile, found space at 2 Little Smith Street.
The Library went into store, in six hundred tea chests and the Library Committee sold off its surplus stock at a shilling a volume. Also removed from the old building was another box claiming to be the genuine box of the self-styled prophetess, Joanna Southcott (1749-1814), containing a solution to the nation's troubles. One such box was opened by the Bishop of Grantham in the Hoare Memorial Hall in July 1927 but was found to contain nothing more revelatory than a novel, The Surprises of Love; or an Adventure in Greenwich Park, and a yellow nightcap, supposedly having once belonged to Miss Southcott.
During rebuilding it was arranged that the Assembly should hold its sessions at the Methodist Central Hall. Its most important work in its sixteen years in the Great Hall of the first Church House had been the consideration of proposals for a revision of The Book of Common Prayer, the first since 1662.
In 1927 the Assembly presented a Measure to Parliament which, if it had received the Royal Assent, would have had the force of an Act of Parliament. The House of Lords passed the necessary resolution relating to the Measure but this was rejected by the Commons. The following year the Assembly again presented the Measure (with some minor alterations), only to have it rejected once more, and it was not until 1965 that the Prayer Book (Alternative and Other Services) Measure was enacted.