After being used as a farmhouse for three centuries, Treowen now operates as a conference and functions venue and holds the annual Wye Valley Chamber Music Festival.

The depredations of time and fallen fortune have removed a good deal, but nothing has been added: everything that is there is genuine, unaltered work of its age.

In 1960, the architectural historian Mark Girouard described the house in an article in Country Life (see quote box).

[3] The originally austere façade was altered early in its history by the addition of a porch, with a "classical frontispiece of distressing crudity",[3] and the Jones shield.

[11] In his study, Houses of the Welsh Countryside, (published 1975, second edition 1988), Peter Smith concludes Treowen "is indeed a very magnificent building".

[7] Tyerman and Warner, in Arthur Mee's multi-volume study The King's England, describe it as "one of the finest houses in all Monmouthshire".