Exterior
Plas yn Dre, Bron y gaer and Bron y gaer Mews form a group.
There was formerly a tablet over the entrance of Plas yn Dre reading 'Rebuilt by C Jones 1823'. Plas yn Dre adjoins Bron y gaer at right-angles, and Bron y gaer is earlier, probably late C18.
Long 3-storey range with irregular fenestration, constructed of hand-made red brick (partly painted) on a stone plinth, under a slate roof; clustered brick ridge stack offset to L, and brick end stack to R. Mainly sash windows. Entrance facing N, in angle with Bron y gaer Mews to R: A 2-storey canted porch bay with hipped roof, with 2-light wooden casement to upper storey. To ground floor, entrance to house with late C20 panelled door, is cut into porch bay and aligned with main elevation; a brick relieving arch beneath upper window suggests there was an earlier entrance here. At right-angles to R, a panelled door with lattice-glazed light, and similar overlight, under a segmental head, leads to a through-passage between the properties; in front of porch bay, a lean-to slate canopy on a narrow timber post. Main range has 2 horned 6-pane sashes to attic storey. Aligned below to L, a 12-pane hornless sash under a segmental brick head to 1st floor, and a renewed 16-pane sash to ground.
South side has a 16-pane horned sash to R, and a 4-light wooden casement under a timber lintel to L, inserted later. Stair-light towards centre at mid-level, a 6-pane sash under a segmental brick head. First floor has tall 12-pane horned sash under segmental brick head to L. Attic has 2 windows immediately under the eaves, a horizontal sliding sash to L and a 6-pane sash to R. Long lean-to against W gable end, reached from through-passage to N, the N side with a 12-pane horned sash to upper storey. To S, lean-to wall is slightly angled to R and contains a 16-pane sash, infill of a higher blocked opening with timber lintel; C20 top-hung window to L; flat-roofed block attached to W end.