Dalton Grange, including retaining walls, boundary walls and entrance gate piers

Dalton Grange is a large villa built in 1870-1871 to designs by the architect John Kirk. Constructed in millstone grit bricks with ashlar dressings, it has a slate roof and substantial chimneystacks. The building is mainly two storeys plus attic and basement, designed in the Baronial Gothic style.

The house is situated on Kilner Bank at the end of a long driveway leading north-east off Bradley Mills Road. Because of its position midway down the valley side, retaining walls exist to the north-west and south-east sides, creating a terrace-style plateau upon which the house and its outbuildings sit. The front elevation faces south-west, with a further principal elevation facing north-west across the Colne Valley, which at the time of construction was rural but is now heavily developed and industrialised, containing the Syngenta chemical works. The rear elevation faces north-east and there is a south-east side elevation. Gardens and woodland lie to the north-west, north-east and south-east sides of the house. A yard area and outbuildings also exist to the north-east rear.

The slate roof is laid in diminishing courses and has a tiled ridge incorporating crest detailing and a bracketed eaves. The majority of the windows have quoined surrounds.

The front south-west elevation is a wide three-bay composition incorporating a stringcourse that forms a sill band to the first-floor windows and continues around and across the north-west elevation and part of the north-east elevation. The central bay projects forward as a four-stage tower containing the main entrance at its base. The ground floor is slightly raised, so the entrance is accessed via a short flight of stone steps. It consists of a Gothic-arched doorway, the surround of which incorporates triple half-columns with fluted capitals. The doorway has a tripartite overlight and a hoodmould with foliate stops, and contains a replaced six-panel door. The first floor of the tower has a cross window with quatrefoils in the upper lights and a relieving arch above. Adorning the tower's second-floor level, or third stage, is a carved and stepped datestone with the date '1871' and the initials 'HB' in relief, along with the Brooke family coat of arms and motto 'SINCERA FIDE AGERE' (to act with sincere faith). Above the datestone is a hoodmould surmounted by two carved lions and with foliate stops. The top stage of the tower has a two-light mullioned window set within a Gothic-arched surround incorporating two trefoils that have had their glazing removed and have been boarded over internally. A continuous hoodmould above the window runs around and across the tower's side returns. The tower is surmounted by a bracketed crenellated parapet. The tower's north-west side return is lit by a single-light window at second-floor level and a cross window at the top stage with trefoils in the upper lights, whilst the south-east side return is lit by a single light at second-floor level and a transomed window at the top stage with a trefoiled upper light. An early 20th-century millstone-grit brick lean-to has been added to the upper two stages of the tower on its rear north-east side to provide an access stair to the uppermost room.

The front elevation's left bay forms the south-west side return of a gabled bay facing north-west across the Colne Valley. It has a large cross window to the ground floor with a relieving arch above and paired transomed windows to the first floor. A probable later dormer window with replaced plain glazing exists to the roof. A single-storey billiards room of 1916-1917, designed by Norman Culley, partly projects forward to form the elevation's right bay and has a hipped roof largely hidden from view by a parapet with blind roundel detailing; a cupola-style vent exists to the centre of the roof's ridge. The billiards room is lit by a small single light and a large eleven-light mullion and transomed window with leaded glazing on this side; the leaded glazing is repeated on the billiards room's windows on its south-east side.

The north-west elevation, which overlooks the Colne Valley (views now largely obscured by woodland), is a three-bay composition incorporating a stringcourse that forms a sill band for the first-floor windows. The central bay has a cross window to the ground floor with a relieving arch above. The window's lower-right light has been converted into a doorway and a late 20th-century flight of external steps has been added to provide access. The first floor has a smaller cross window and the roof has a dormer window and a substantial chimneystack. The two outer bays have crow-stepped gables surmounted by substantial pyramidal finials. Each of the gabled bays has a bay window to the ground floor (that to the left bay is canted) with a parapet incorporating blind roundel decoration, and a slightly projecting seven-light window to the first floor with a similarly styled parapet. A cross window with a blind roundel and shaped hoodmould above lights the left bay's attic, whilst the right bay has a single-light window with a stepped hoodmould.

The rear north-east elevation has, set back on the right, the three-bay north-east return of the north-west valley-facing elevation, which maintains the styling of the principal elevations and has a stringcourse and central wall stack incorporating a carved panel depicting a serpent-like creature whose tail morphs into foliage. Windows containing replaced casements flank the stack on both floors and a small dormer window exists to the roof. The glazed upper section of a basement door is also visible, although the access well to the door has been infilled. A wide gabled cross-wing on the left projects forward with shaped kneelers and was probably the service wing originally. It has relatively narrow windows to each floor with plain lintels and sills, including two windows that flank a corbelled wall stack that projects at attic level and has been truncated slightly and capped. A wide mid-20th-century window has been inserted at first-floor level and a later ventilator has been inserted to the ground floor. Attached to the far left of the elevation at first-floor level is a 1964-1965 flat-roofed extension that spans the access into the rear yard and rests atop part of the south-east retaining wall; the extension is not of special interest and is excluded from the listing. The cross-wing's north-west return maintains the stringcourse of the elevation's right bay and has large cross windows with quoined surrounds to each floor.

The south-east elevation is largely hidden from view by the restricted site on this side of the building. The south-east return of the billiards room is lit by three single-light leaded windows. A large first-floor eight-light window that lights the stair hall is hidden from ground-floor view by the billiards room but contains patterned leaded glazing and has trefoil-arched lower lights and quatrefoils to the upper lights. The ground-floor service doorway and windows at the right north-east end of the elevation remain and are now contained within the tunnel-like access into the rear yard created by the 1964-1965 flying first-floor extension.

Internally there are deep skirtings throughout the building, along with moulded door and window architraves, panelling below the windows, floorboard floors (hidden under later coverings), cast-iron radiators, and some moulded cornicing. Some original four-panel and six-panel doors survive, but some have been replaced. A small number of suspended ceilings have also been inserted in places and some walls have been knocked through. Fireplaces have generally been removed, but chimneybreasts survive. Since the late 1960s, steam from the neighbouring chemical works has been piped to the house and supplies its heating system.

The main entrance leads into a large vestibule that has decorative moulded cornicing, a ceiling rose, and modern flooring surrounded by an original patterned encaustic tiled border. An inner Gothic-arched doorway in a similar style to the external doorway with replaced glazed double doors leads into a long and full-height Baronial-style stair hall with decorative moulded cornicing and a ribbed ceiling incorporating floral bosses and shield reliefs of the Brooke coat of arms. The stair, which has Y-shaped balusters, a substantial Gothic-style newel post, a closed string incorporating quatrefoil roundel decoration, and cusped panelling to the lower part, consists of a long single flight incorporating a half landing that lies alongside the right south-east wall and is lit by the large stair window detailed above. A wide first-floor landing then runs down the left north-west side of the stair hall, continuing the stair balustrade and incorporating a Gothic-arched opening at the south-west end. Underneath the landing is additional decorative moulded cornicing. At the far north-east end of the stair hall is a late 20th-century bar servery.

Later multipaned double doors off to the front right of the stair hall, inserted circa 1974, lead into the 1916-1917 former billiards room, which has a barrel-vaulted ceiling incorporating full-width Diocletian windows at each end, panelled walls, and Doric-style pilasters. A chimneybreast lies to the north-west wall, but the fireplace has been removed. A late 20th-century bar servery has been inserted into the room's north corner and incorporates the original entrance into the billiards room.

Another set of similarly styled doors and a single door lead off to the left of the stair hall into two north-west facing rooms that have been opened up to form a single space and a sliding partition inserted. Both spaces retain evidence of the former position of fireplaces; one has a chimneybreast, whilst the other has an inserted ventilator. The north-eastern space also has a modern dancefloor. A door off the north-eastern space leads into another smaller reception room, which has been subdivided to form two storage spaces, with doorways inserted to access a probable former service area to the rear right of the building that is now a commercial kitchen. Access to these rear areas is also off to the rear right of the stair hall.

A secondary dog-leg stair, which leads up to the attic, exists to the rear right of the building and has turned balusters and a newel post with chamfered corners and a ball finial. The stair's Gothic-arched window with patterned glazing and decorative stained-glass margin lights is no longer external due to the construction of the late 20th-century first-floor extension.

The first-floor rooms are generally plain and have incurred some later alteration. A former bedroom at the head of the stair has been converted into ladies toilets and a powder room, and one of the bedrooms on the north-west side with a lozenge-shaped plaster moulding to the ceiling is now a billiards room with a vinyl floor covering and table platform. A bedroom at the west corner has also been partitioned to create a lobby/storage area and an en-suite bathroom. A small room, possibly a linen closet originally, at the southern corner of the first floor now contains an early 20th-century cast-iron spiral stair leading to the upper floors of the tower. An altered lobby area off to the right south-east side of the first-floor landing adjacent to the secondary stair has a wall knocked through and new doorways and partitions inserted to create access into the 1964-1965 extension at the rear right of the building, which contains a modernised flat.

The attic has a C-shaped corridor lit by Soaneian-style skylights with rooms off to the north-west side and south-west and north-east ends. A fireplace with a glazed-tile hearth survives in one of the rooms, and an original cast-iron bath also survives in a modernised bathroom. Some built-in cupboards also remain. The tower's top-floor room retains its original hatch access in addition to the later spiral stair.

The basement is accessed via a stone stair flight underneath the secondary stair and consists of a number of rooms with stone-flag floors. Some stone larder shelving survives in at least one of the rooms.

To the north-east rear of the building is a large yard area with a millstone grit wall with triangular copings along its north-west boundary, from which a high crenellated wall projects at a right angle and separates the yard into two areas; the area nearest the house originally contained a glasshouse, depicted on the second edition Ordnance Survey map published in 1893, but this was demolished before 1907. A rebuilt single-storey garage range with a lean-to roof occupies the south-east side of the yard. This was originally a stables and coach house range that was seriously damaged by fire circa 1970 and has since been rebuilt and reduced in height to single-storey; the garage range is not of special interest and is excluded from the listing.

A retaining wall to the north-west of the building has flat-topped triangular copings, whilst another retaining wall to the south-east side has flat copings and is stepped at its south-west end.

At the south-west end of the driveway are two crenellated sandstone gate piers; that to the left has inscribed leaded lettering to the front face that reads 'DALTON' and that to the right has similar lettering that reads 'GRANGE'.