Trevor House was probably the substantial house known as Plas Iva, first mentioned in 1660 when an assessment was raised on it to fund a new militia. The present building may incorporate an earlier building, as the ground floor front wall stands proud of the upper floor. The rear of the house appears to date from the seventeenth century, built of timber framing, probably by the Myddleton family although in the township of Brynkinallt. The present front block (to the south) was altered and enlarged in 1840 probably by Richard Jebb, the agent to the Myddleton estate.
Source, Cadw Listed Building Database, record number 617.
David Thomas, RCAHMW, 17th September 2007.