The site of Inveresk, 17 Armagh St, was originally granted to Church Property Trustees in 1858. In 1863 the site was transferred to Withnall, to George Roberts in 1872, and then to Violet Cobb in 1875. Between 1863 and 1878, a small single storey cottage was built on the site. In 1879 the property was sold to John Anderson Jnr.

John Anderson Jnr. (1850-1934) was the son of John Anderson (1820-97), pioneer, second mayor of Christchurch (1869), and founder of the Canterbury Iron Foundry (1857) - the first in the city. Born in Edinburgh in 1850, John Jnr. came to Christchurch later that year with his parents aboard the 'Sir George Seymour', one of the First Four Ships. Returning to Scotland in 1866 with his brother Andrew, he was educated at Merchiston Castle, Edinburgh, and studied mechanical engineering with the firm of P & W McLellan in Glasgow. John Jnr. joined his father in the family foundry following his return to Christchurch in 1873, took over the business with his brother in 1881, and assumed joint ownership following his father's death in 1897. After the foundry became a limited company in 1903, John Jnr. served as chairman of the board of directors until his death. Like his father, John Jnr. was civic minded. He served on the Christchurch City Council, was president of the Canterbury Agricultural and Pastoral Association, a director of the New Zealand Shipping Company, a member of the Chamber of Commerce, and a member of the Board of Governors of Canterbury College. In 1879 he married Frances Pratt, and they were to have five children. Frances was the daughter of William Pratt, whose drapery business 'Dunstable House' formed the basis of Canterbury institution, Ballantyne's, in 1872.

Anderson's Foundry played a vital role in the early development of engineering in the colony. The firm constructed many early bridges in the colony, and built mining dredges, cranes, boilers, and other heavy machinery. Anderson's was also involved in constructing sections of the main trunk railway in the North Island. The foundry, one of Christchurch's oldest and most successful businesses, closed in 1986 after 136 years of operation. The original foundry buildings were subsequently demolished.

During the 1870s John Snr. built a new home for his family in Cashel St, close to St Paul's Presbyterian church. This house he named 'Inveresk' after his birthplace in Midlothian, near Edinburgh. Inveresk was sold in 1907, and it was presumably at this time that John Jnr. adopted the name for his Armagh St property.

As John and Frances's family grew, the Armagh St Inveresk was enlarged. In about 1880, a two storey domestic gothic portion was added to the south and west of the original cottage. Then in 1890, an ornate single storey villa was added to the south of the gothic portion. Inveresk was the fifth house in Christchurch to be connected to the sewer, and one of the first twelve houses to be connected to electricity.

The Anderson's used Inveresk and its once extensive gardens as a 'centre of much entertainment'. In 1900 an Anniversary Day function was attended by most of the surviving passengers of the First Four Ships. Sixty years later, Pilgrim and Early Settlers Association members gathered at the house for a garden party.

One of the Anderson's daughters, Dorothy, cared for her parents, and remained at Inveresk until her death in 1967. The house was then sold by the family to the Church Property Trustees, who transferred it to the Cathedral Grammar School Trust Board in 1972. Inveresk subsequently served as the headmasters' residence. Internal alterations were carried out in 1973 and 1986. During one of these alterations, the house was divided into two flats; one upstairs, and one down. By the 1990s some rooms were unoccupied, and being used for storage.

In 1994 Cathedral Grammar School announced the formation of a new girls' school, and that Inveresk would be removed or demolished to provide a site for the necessary new premises. After intervention by the Christchurch City Council and NZHPT, the school decided in 1995 that the house could be renovated to serve this purpose. Architects Trengrove and Blunt carried out the alterations. Although the exterior remained substantially unchanged - with the exception of a new bay window on the west elevation - the ground floor interior was significantly modified. A number of walls and chimneys were removed to provide classroom space. Upstairs, a self-contained flat was initially maintained, but later integrated into the school as a classroom in 1997.

In 2001 Cathedral Grammar applied for resource consent to demolish the rear sections of Inveresk, and replace them with a new two-storey structure to provide more classroom space for the Girls' School. The demolition was opposed and after consultation the application was withdrawn. The Girls' School remained in Inveresk until the end of 2003, after which they moved to a purpose-built building elsewhere in the Cathedral Grammar grounds. The vacant house was subsequently leased to E-time, a new company established to provide electronic learning opportunities to Canterbury schoolchildren. Internal alterations were again carried out by Trengrove and Blunt, and E-time opened for business at the beginning of 2004.