Castellau Congregational Chapel

Entrance vestibule with panelled doors to L and R opening to gallery stairs. Canted doorways leading into chapel, panelled and half-lit with geometrical stained glass. Late C20 frosted glazing between doors. The chapel has a 3-sided gallery on cast iron columns with small foliate capitals. The wood panelled gallery front has a band of cast iron openwork bearing a frieze of trefoils with small leaves. Pipe organs, painted white, are mounted above the N ends of the gallery. Pews with panelled backs and carved bench ends to main chapel and gallery. A screen in front of the ground floor pews has iron openwork as gallery. Octagonal panelled pulpit, the upper tier with cast iron circle decoration. Dog-leg stairs to either side with turned balusters and square newel posts. Behind the pulpit is a blind moulded plaster archway with pilasters, dentilled capitals and a trefoiled head with circle beneath. Triangular hoodmould over with fleur-de-lis finial. The arch is flanked by pointed arched windows with Y-tracery, which would have been external before the vestry was added. Flat headed doorway to L of pulpit leading to vestry. Canted ceiling including highly ornate plaster ceiling rose to centre in high relief with foliage. Smaller flanking ceiling roses with foliate decoration. Pierced louvre openings in canted sections, 2 to each side. Stained glass in geometrical design to later W window. The E window of the vestry also contains stained glass.

Small chapel in Gothic style with gable end entrance and 3-window side walls. Constructed of narrow coursed stone under a slate roof, with sandstone dressings and a plinth. At the 4 angles are diagonal buttresses with offsets surmounted by tall pinnacles. Tall pointed arched windows with Y-tracery, 2 transoms and hoodmoulds with head or foliate bosses. The doorway to the S gable end is chamfered with a pointed-arched head and contains C20 double planked doors. It is flanked by tall pointed arched windows. Above the doorway is a rectangular stone tablet reading 'Independent Chapel Castellau, Built AD 1843, Rebuilt AD 1877'. Above the tablet and lighting the gallery is a replaced 3-light window under a round head with wooden tracery including a transom. Head bosses survive to each side of the arch, probably relating to the earlier stepped window. In the gable apex is a keyed oculus, the opening boarded over. String course following line of verges which continues around pinnacles.

The tall windows of the side walls are divided by angle buttresses with offsets which continue to eaves level as pilasters. The eaves are decorated with bosses bearing the heads of men and beasts. The N gable apex has a keyed oculus containing a louvre. Below is an added lean-to vestry which projects to the rear (W). Its E side contains a planked door with overlight to the L and a 2-light window to the R, both under flat heads. The N side is rendered and has 2 C20 3-light windows with flat heads.