The mansion of Pibwr-Lwyd incorporates part of a late medieval-sixteenth century house. The present building is mostly seventeenth century, remodelled in a late Georgian Regency style and extended in the early nineteenth century. The estate was sold to Carmarthenshire County Council in 1919 to house a technical and agricultural college.

The main house is a north-west to south-east range, two storey with attics. It has roughcast rubble stone walls under a renewed slate gabled roof. The elevations are irregular although some attempt at rational composition has been made for the south-west facing entrance front at the north-west end of the range. The south-east part of the range is the early house, divided from the remainder by a thick cross wall on the ground floor and a change in level in the attics. The south-east gable wall has a blocked late medieval arched doorway below a fragment of corbel table that may have supported a projecting first floor chimney. The building may have been a first floor chamber block attached to a now vanished hall.

The house was extended to the north-west in the seventeenth century. Roof trusses of this period have been identified and it is thought that the massive gable-end stacks are of this date. There is a similar, but smaller projecting stack on the south-west wall of the early house. The attic fittings are eighteenth century.

In the early nineteenth century the house was refenestrated and a block was added on the north-east, producing an overall L-plan. This block is two storey with a short, almost pyramidal, hipped roof. The fenestration features large tripartite sash windows recessed in blind eliptical arches and pointed windows with Gothic tracery, as well as 'regular' sash windows. The doorway is also of this period and has a semi-circular fanlight. A long single storey range was added on the south-west.

The interior has been much altered. There remains a nineteenth century staircase and elliptical niches in two rooms. The first floor and attics show considerable traces of early nineteenth century stencilled painting, employed as an alternative to wallpaper.

Associated with: outbuilding range (NPRN 31641)

Sources: NMR Site File
CADW Listed Buildings Database (9733)

John Wiles, RCAHMW, 22 October 2007.