The following text is from the original listed building designation:
LEYBOURNE CP BIRLING ROAD TQ 65 NE (west side) 7/197 - Leybourne Grange
- II
Country house, now administration building for Leybourne Mental Hospital. Circa 1850 by S W Dawkes. Stuccoed facades with raised quoins to central and end pro- jections on 1st 2-storey and panelled pilasters to attic storey. String course between ground and 1st floors, cornice between 1st and attic floors and parapet with cornice moulding over attic. Slate hipped roofs, masked by parapet with various stacks, 2 of which stand in centre of parapet of end projections and are arched on line of parapet. Central projection crowned by pediment broken by open pedimented medicine framing coat-of-arms. 2 storeys and attic, the attic forming an almost complete 3rd storey. Regular 11-bay facade, though the central projection is divided into 2 bays on attic storey with a single triple-arched window below. Pair of windows flanking central entrance. Glazing bar sashes throughout except sashes on ground floor and sashes without glazing bars in central lst floor window and in 2 windows flanking main door. Ground and 1st floor windows have segment-headed eared surrounds with cill brackets. Central ground floor ponte-conchere with balustrade over 6 columns, paired at each end and with single columns dividing the wider central opening and the narrower flanking openings. Doubled half-glazed doors behind, with overlight.
Listing NGR: TQ6858258935

Description from record TQ 65 NE 98:
Grade II building. Originally a country house, it later became part of Leybourne Colony/Mental Hospital in the early 20th century. The hospital has now closed and the site is up for housing development (2005).

In the late 14th century the estate containing Leybourne Castle was bequeathed to the Cistercian Abbey of St Mary Graces, London, and it has been suggested that this was when the 'grange' - a farm belonging to an Abbey - was first created. In 1724 Francis Whitworth acquired the entire Leybourne estate, including the grange. He pulled down the existing grange and built a new structure. Leybourne Park was laid out at this time with a summerhouse, fishpond and avenues.

The present Grange was designed in 1850 by SW Dawkes. It was converted into a hospital complex in the 1930s. The hposital closed in 1994. (1)

The first house was built in 1725, it appears on the Tithe Map of 1842, consisting of a central range and two connected side ranges at the front. This structure was replaced by the current building in 1850. It is possible that the vaulted cellars and the panelling in one of the ground floor rooms belong to the earlier structure. The house was purchased by Kent County Council in 1928 and converted into a hospital. A photographic survey of the interior was carried out in 2011. (2)

Historic England archive material: 91/00845 Hospitals Project architectural drawings copying Copies of measured drawings owned by South-East Thames Regional Health Authority held at Bexhill-on Sea.
BF101223 LEYBOURNE GRANGE, BIRLING ROAD, LEYBOURNE Miniature Format Film Number: 149/Y

<1> NHS, 2003?, Leybourne Grange environmental statement (Unpublished document). SKE15636.

<2> Architectural History Practice Ltd., 2011, Heritage Statement Leybourne Grange, Leybourne, Kent Kent 2011 (revised 2012) (Unpublished document). SKE24855.

<3> Architectural History Practice, 2012, Leybourne Grange, Leybourne, Kent, Heritage Statement (Unpublished document). SKE52372.