Llanthewy Road Baptist Church and attached Sunday School wing

Large chapel in Anglican style. Of snecked coursed rubble with pale ashlar dressings and Welsh slate roof. Plan of nave, transept-type bays, porch bay with adjacent tower; attached Sunday School and hall wing. Asymmetrical gable-end facade is dominated by a large window of 6 lights with quatrefoil tracery, hoodmould and foliage stops, to left a single cusped light. Below is the projecting porch bay with single pitch roof, steeply gabled and heavily moulded entrance doorway with paired colonnettes and overlight with cusped tracery, the quoins tapered to the kneelers; cusped lights either side, low buttresses and a second door to left. To right and breaking forward is the slender tower with full height angle buttresses with shallow offsets. Crenellated parapet incorporates cross; below a string course is the ringing chamber with tripartite louvred openings, heavily moulded with hoodmould and slender columns; lightly cusped lancets to tower chamber with below a blind arcade frieze across 3 sides of the tower; at ground level the tower doorway is similar to the main entrance; dedication stones at the base of the buttresses. Side elevation to road accommodates steep slope and has a lower ground floor. Deep steep-pitched roof with 3 ventilators, 4 window range of paired cusped lights with quatrefoil tracery separated by long slender buttresses without offsets. Gabled cross wing has similar window to gable end, trefoil gable light and cross-framed windows to lower ground floor; further lower entrance bay attached to right. On the opposite side the cross wing links with the Sunday School which has similar cusped-headed lights, paired and triple, and central gabled porch with overhanging eaves and moulded pointed arched doorways to each side. Paired lights to side separated by tall chunky buttresses with swept offsets; lower level rectangular windows to right are blocked.

Airy interior, with wide pointed chancel-type arch supported by corbels with clustered half-colonnettes; no gallery. Boarded wide-span hammer-beam style roof with ventilators, supported by heavy corbels. Interior is dominated by a semicircular apse-shaped baptistry with stepped red terrazzo floor incorporating an unusual raised grey terrazzo baptismal pool for total immersion. Cusped lights either side of arch, large 3-light window with quatrefoil tracery to baptistry; matching side windows of 2 lights with quatrefoil tracery; some figurative glass by Pearce and Cutler of Birmingham, other windows are of tinted glass with some decorative tracery leading. Interior is fully pewed with boarded dado; organ left and pulpit right; half glazed doors to outer rooms and passages. Vestibule has boarded dado, half glazed swing doors with boxed entrances to sides and central doorway flanked by paired cusped headed lights.