Lillington Gardens Estate was constructed in three phases between 1961 and 1972. The design took its cue from the striking Victorian red brick of the Grade I-listed Church of St James the Less, which the estate surrounds. This source of inspiration was unusual in the 1960s, but the brown Hastings-made red brick and staggered terraces swiftly became part of what makes Lillington Gardens so iconic.

In their work at Lillington Gardens, Darbourne and Darke explored the combination of brick and concrete with an intensity of tone and complexity of form that had never been achieved before. The design broke with the trend for standard units in high-rise blocks, instead emphasising the individuality of group dwellings and achieving high densities with eight-storey blocks. The general plan of the building is described by Pevsner as "ingenious", with "internal courtyards and cross-wings threaded through with paths and ramps. [The] higher levels are reached by brick-paved internal streets."

Lillington Gardens initially housed 2,000 people within its grounds, which also included a pub, grocery shops, surgeries, a community hall and a library. The scheme won a Housing Design award in 1969, a Ministry of Housing and Local Government award for good design in 1970, a RIBA Architecture Award in 1970 and a further RIBA commendation in 1973.

In 1998, English Heritage granted Repton House a Grade II* listing in recognition of its special architectural and historical significance.