1. A sub-medieval farmhouse of regional 'end-chimney' type, probably dating from the seventeenth century, it was remodelled in the late nineteenth century with a central wooden stair, boarded partitions and alterations to the windows.
"The house is two-storey with attached byre (R), and rear wing. Local rubble, slate roof under restoration at time of inspection. Two large square chimneys. Two window front faces W; wooden casement glazing, with upper windows at eaves. Roughly central doorway with deep stone lintel; boarded C19 door. To R of house, byre with roughly dressed roof trusses; loading door in R gable where ground rises. At N end, single-storey rear wing at right angles in matching materials. At S end, lean-tos at front (ruinous), and rear corner (roofless). Traditional regional layout internally comprising hall with parlour and service room, originally with chimney stairs in hall, the original plan modified by the insertion of a central staircase in the C19. Heavy chamfered beams, chamfered joists. Deeply splayed window openings. Room to R has large fireplace with C19 range; to R of this, stone fireplace stair. On upper floor, roof ceiled but feet of trusses visible as are some heavy purlins." (Source: Cadw Listings database)
S Garfi, RCAHMW, 24/10/2006.

2. Tree-ring dating commissioned by Cymdeithas Hanes Beddgelert and RCAHMW. results reported in Vernacular Architecture 38 (2007) with notes by R. Suggett, Daniel Miles and Margaret Dunn:
"14. MAENTWROG, Cae'nycoed-uchaf (SH 6827 4065)
(a) Primary phase, Felling dates: Summer 1576; Winter 1578/9; Spring 1579
(b) Alteration or repair phase? Felling date: ?Summer 1593
(a) Principal rafters 1578(45?C2); Rafters (1/2) 1578(32C); Transverse beam 1577(31?C); Joist 1575(42?C); Collar 1565(22+7 NM); Mantel-beam 1509(h/s); Tiebeam (0/1); (b) Joist 1592(31?C?). Site Master 1407-1592 BDGLRT17 (t = 10.7 BDGLRT22; 10.0 BDGLRT10; 8.4 WALES97; 8.3 BEDD_T6)" A storeyed stone-built house of classic two-unit Snowdonian type with end chimneys and stone fireplace stair. Timber detail includes a: post-and-panel partition dividing hall from outer rooms; a timber diamond-mullioned window to the hall; a plain mullioned window to the service-room; and heavy trusses with morticed collar beams and trenched purlins.
R.F. Suggett and D.P. Jones, RCAHMW, July 2007.