Pant-glas uchaf

Pant-glas Uchaf is a building constructed from local rubble stonework with flushed joints, resting on boulder foundations. It features a Twll Llwyd slate roof with a gable end stack that has drip courses on the higher southern section, and a second stack added in the 1950s at the junction with the earlier, lower northern range. Long basalt columnar tie stones bedded in sphagnum have been recorded by the Royal Commission on the Ancient and Historical Monuments of Wales.

The lower range is single-storey with an attic and includes a boarded door with a chamfered lintel, flanked by small windows set in deep reveals—one with original splayed jambs and the other inserted. There are also two-light casement windows and a gabled dormer in the rear wall, which were added later. The higher southern section has a timber door and two-light casement windows, one on each floor, set deeply in reveals and unaligned. The upper window is located in a simple dormer that was originally designed with a cat-slide roof and later modified to a gable around 1890. A later rear wing, which has been partially reconstructed, includes a lean-to conservatory added during renovations in the 1980s.

Inside the southern section of the house, there is one room on each floor. The ground floor features three chamfered cross ceiling beams and deep stop-chamfered joists, along with a gable end fireplace that has a high-set lintel and broach chamfer stops, and a stone spiral stair on the right. The floor is slate. The upper room has a tapered principal roof truss with a high-set collar supporting two purlins on each side. The eastern principal truss bears an inscription from a later date, reading "1562 / RW." A doorway near the front wall of the main ground floor room opens into the northern range, although the internal arrangement of this section reflects work done in the 1980s. Nevertheless, the original roof timbers remain, consisting of two trusses with morticed collars.