Britannia Mill

Britannia Mill

A former cotton weaving mill built in 1855 with substantial alterations in 1895 and 1916. The complex comprises a three-storey preparation block at its core, flanked by a single-storey north-light weaving shed, with a powerplant (engine house, boiler house and chimney) and a two-storey office building to the south and east, and a three-storey extension block added in 1916 to the north.

The structures are built primarily of local yellow sandstone, squared and laid to courses, with some later brick additions. Roofs are covered in Welsh slate.

Preparation Block

The three-storey preparation block is orientated east-west, eight bays wide, with a single double-pitched roof. Fenestration is regular, featuring tall segmentally arched windows with stone slab sills, most retaining 12-pane fixed-light timber windows. The ground floor north elevation has been modified with brick jambs and concrete lintels. Both gables are stone coped; the east gable retains a scar line believed to mark the original two-storey engine house. Adjacent to the west gable, the ridgeline is pierced by a square projection housing the headgear of an internal hoist.

Internally, all three floors are supported by a central row of hollow cast-iron cylindrical columns bearing substantial timber beams, with timber joists spanning between them to support floorboards. The ground and first floor columns are identical, each featuring a flat bolting plate on the north side for a line-shaft hanger, designed to allow height adjustment. The second floor columns are thought to be late-19th or early-20th-century replacements with multiple flat bolting faces for line shaft hangers. The building retains further evidence of the power transmission system: bearing boxes built into walls and bolt holes through ceiling beams for hangers. A brick-walled stairwell in the south-east corner provides vertical linkage, supplemented by an inserted hoist positioned centrally to the west gable. The ground floor has been subdivided by later partitions; the upper floors remain open. The roof is supported by queen post trusses, with the top floor ceiling beams acting as tie beams. The attic is floored but accessible only via a ceiling hatch.

1916 Extension Block

This three-storey block extends north-south from the west end of the original preparation block's north elevation. It is constructed of regular, machine-cut, rusticated yellow sandstone blocks laid to regular courses and bedded in cement. The roof consists of three two-bay spans transversely arranged, with a single-bay span at the north end. Windows are very regular, with four to each floor on the north elevation and seven bays on both east and west elevations; most retain 12-pane fixed-light timber joinery, though some openings have been blocked or converted to doorways. The ground floor east elevation includes large loading doors with steel lintels at both ends. A small chimney rises from the north-west corner.

Internally, all three floors are supported by a central row of cast-iron columns carrying steel beams, which in turn support timber joists and floorboards. The top floor is open to the roof, with columns supporting the timber roof structure. All floor columns incorporate bolting faces for line shaft hangers, except the two southern ground floor columns, which occupy a separate loading bay. This bay has a floor of stone sets and flagstones and features a hoist and conveyor belt rising to the upper floors. Doorways on the ground and first floors connect to the earlier preparation block. On the top floor, a three-bay-wide break-through is supported by a steel joist held up by iron columns.

Powerplant

The engine house is built of rubble sandstone with dressed sandstone quoins. Attached to the weaving shed and boiler house, only its north wall is external, set back from the mill yard. This elevation features a tall central window with a slightly embellished cast-iron lintel dated 1895; the lower portion is blocked with brickwork. The top of the engine house carries an embellished cast-iron water tank. The boiler house to the west is utilitarian, constructed of machine-made brickwork and thought to be a later addition. The chimney, dated to the 1850s, survives to full height of approximately 30 metres, built of regularly coursed sandstone blocks with a simple band near the top and gently tapering.

Within the engine house, the northern third has been subdivided to form part of an electricity substation. One transmission shaft with belt wheels survives in situ, extending west from the engine house to the east gable of the preparation block. Various blocked openings mark the positions of other line shafts and bearing blocks. The boiler house retains later coal-fired heating boilers rather than original steam-raising boilers.

Weaving Shed

The single-storey weaving shed features a north-light roof of 10 spans. Its perimeter walls are constructed of blind random sandstone rubble, punctuated only by cast-iron downpipes serving the valley gutters.

Internally, the shed is largely undivided except for a short corridor section adjacent to the engine house leading to the mill yard to the north. The timber north-light roof structure is typical of early weaving sheds, with valleys spaced 20 feet (6.1 metres) apart, supported by columns spaced at regular 10-feet (3.05-metre) intervals. The columns are slim, cylindrical, hollow cast-iron; most feature a single bolting face for a line-shaft hanger. The southernmost run of columns is of a different design, more typical of the late-18th or early-19th centuries, with an open head through which the line shaft would pass and a horizontal bearing plate for a bevel gear.

Office Block

This two-storey building with a pitched slate roof is utilitarian in character, constructed of random sandstone rubble walls with stone slab lintels and sills. It is four bays wide with gable-end stacks and scattered fenestration, the ground floor being better lit than the first floor.

Internally, the space is undivided, with the timber first floor supported by iron stanchions and the ground floor flagged.