The building of the school, and the rest of Harperbury, commenced in 1929. The architect was W T Curtis, the county architect of Middlesex, and he drew up the plans for both Harperbury and the neighbouring Shenley Mental Hospital. The hospitals themselves were built by John Laing, employing up to 700 labourers at times. The male patients of The Hangers Certified Institution helped build their new accommodation and by 1934, the brand new Middlesex Colony was finished.

Curtis used the villa layout, building his hospital from a number of discrete buildings and pavilions, rejecting the huge, monolithic structures of the Victorian era. With the central core (admin, recreation hall, workshops, laundry and boiler house) occupying the central part of the site (aligned on a rough north-south axis), the patient’s villas occupied three loops: one for the male patients, one for female, and finally one for children.

The children’s “loop” also included a school and swimming pool, both which we’d already found. So, our exploration of Harperbury became more defined as we realised that our immediate area was designed and built for children.