Sir Joseph Bradney described Wern-ddu as "in its origins one of the oldest in the county".

[2] Sir Cyril Fox and Lord Raglan, in the second of their three-volume history of vernacular architecture Monmouthshire Houses, give a date of c.1675.

The American journalist and diplomat Wirt Sikes, United States consul at Cardiff in the 1870s and 1880s, recorded an encounter between its last hereditary owner, Roger ap Probert, and a stranger, in his Rambles and Studies in Old South Wales, published in 1881.

[2] It is built of rendered Old Red Sandstone rubble and is of two storeys with attics, and a three-storey stair turret.

[1] It contains an important staircase, which Newman considers "a fine piece"[2] and a "coffered wooden ceiling with bold mouldings".