Cathays Methodist Church including Sunday School attached to rear.

Neo-classical style with towered facade fronting very rare basilician chapel with clerestory. Built of coursed, rock-faced Pennant sandstone with Bath stone window surrounds, dressings and Bath stone string courses interspersed with red brick. Slate, stepped-pitch roof over main building. Tall and imposing gabled front, formerly with openwork cupolas to domed roofs of stair towers. Central entrance obscured by later vestibule; twin, round-headed windows to first floor and circular window with simple tracery in pediment. Flanking and slightly-projecting stair towers finished with pediments on each side and with round-headed doorway on lower floor and round-headed window framed between pilasters on upper floor. Side elevation of stair towers incorporate two small round-headed windows at lower floor rising to reflect stairs inside. Side elevation of chapel divided into five bays by pilasters and tall round-headed windows with stepped yellow brick surrounds. Small round-headed windows with Bath stone surrounds in groups of three to each bay at clerestory level. Front elevation of Sunday School in three bays with gabled end bays incorporating slightly pointed windows in echelon with Perp tracery and flat-topped centre bay with two doorways and above slightly pointed window couplets.

Original chapel space divided vertically into two separate rooms. Lower room retains gallery balustrading (painted over previously varnished wood-work) on four sides, supported on round, cast-iron ground-floor columns with Tuscan capitals. Upper room retains round, cast-iron columns (at former gallery level) with composite capitals and semi-circular linking arches between columns. Raised centre section of roof with flat, boarded ceiling and round-headed clerestory windows in triplets; two ceiling ventilators replaced by flat panels. Ceilings to aisles supported on simple triangular, wooden trusses. Large, pre-1914 organ by Harrison and Harrison of Durham, in grand, semi-circular recess behind modern pulpit. Chapel originally had pews to seat 850. Room below original chapel has round cast-iron columns and is divided into smaller rooms by partitions.