13 Castle Square

13 Castle Square, part of the Paternoster Buildings, is a group of shops and dwellings built in a simplified Baroque style. The building has three storeys and an attic, situated on a corner site with a splayed angle. The roughcast walls are painted cream, and the hipped slate roof slopes to the right, featuring three roughcast chimney stacks.

The facade facing Castle Square consists of three paired bays, with rusticated pilasters on the lower storey and full-height Corinthian pilasters on the middle and upper storeys. A broad entablature below the eaves displays the name 'Paternoster Buildings' in raised letters. The windows on the middle and upper storeys have architraves. In the left-hand bay (No 12), there are renewed 4-pane sash windows; the central bay (No 13) also has 4-pane sashes, while the right-hand bay (No 14) features windows that have been replaced in their original openings. Both the central and left-hand bays include two segmental-headed roof dormers with opening lights.

The left and right bays have late 20th-century shop fronts. The shop front of the central bay (No 13) includes half-glazed panelled doors on the right and left, a window with glazing bars, and round vents on the stall board. The fascia has been replaced.

To the right, there is a narrower single-window splayed corner bay, followed by a bay facing Bridge Street that has replaced tripartite windows and pilasters similar to those on the Castle Square elevation. At the rear, there is a single bay facing Lon Crwyn, which ends with a pilaster that matches the main elevations. Beyond this, the rear features five windows, most of which have been infilled.