Coach-house at Porth Mawr & adjoining boundary walls to SW end and NE to Gate-house on Brecon Road

The coach-house at Porth Mawr, along with the adjoining boundary walls to the southwest and northeast to the Gate-house on Brecon Road, is a two-storey and attic, three-bay structure built from rubble with a slate roof. It features a weathervane at the ridge and a brick chimney stack. The central bay is advanced and gabled, showcasing plain bargeboards and wide eaves, along with a circular attic window. There is a boarded opening on the first floor beneath a timber lintel and cambered voussoirs, which was formerly fitted with a bell. The ground floor is constructed from coursed rubble and includes paired cambered-headed coaching entrances with voussoirs and keystones, leading to double boarded doors. To the left, there is a smaller entrance next to a horizontal sliding sash window, and a similar arrangement is found to the right with an adjoining lower outbuilding. The plain rubble gable ends also feature circular attic lights set in brick surrounds. The rear wall displays a vertical joint and includes two boarded and two open loft doors, along with a three-light timber window for the outbuilding.

Adjoining to the right is a part castellated wall, which is raised near the corner and has double boarded doors. There is a pointed chamfered arch opening further along before the wall terminates against the Porth Mawr Gatehouse on Brecon Road.