Probably built slightly later than Trevalyn Hall of 1576 to which it is connected and for which it acted as the service wing until sold in 1984. It has been suggested by Mark Girouard that together with Trevalyn Hall, the linking corridor, and Porters Lodge, the entire site represents an uncompleted Elizabethan house for John Trevor, the eastern and southern wings having been completed but the central section, which would have contained a Great Hall and been connected at the north ends of the surviving buildings never completed. Foundations for such a Great Hall were found when new gardens were laid out to the north in the mid-C19. The designer is unknown but Girouard suggests that it was John Trevor himself with the assistance of master-mason Walter Hancock of Much Wenlock. The estate was sold in 1984 to property developers who subdivided the Hall into two flats, sealed the Service Wing off from the link corridor and re-named it "The Courtyard".

Constructed of brick with stone dressings on a stone plinth of five exposed courses. The eastern facade is a copy of the western elevation of the Elizabethan style of Trevalyn Hall, i.e. projecting cross wings to north and south of two storeys plus attic storey. On a H-plan but with single storey later additions to north, south, and western facades. Large stone mullion and transomed windows to two storeys with double-light blind attic windows to stone coped, and tulip shaped finialed, gables. Windows to first and attic storey have triangular pediments. Pediments to first storey contain armorial bearings. Brick chimney stacks to the inside returns of cross-wings. Central section of three bays with large stone four-light transomed and mullioned windows to second storey. Link corridor joins at first storey. To the south wall of the south cross-wing is a later single storey extension which may have been the principal entrance after the removal of the linking corridor and Porters Lodge in the 1830's. In use as a stable at the time of re-survey. To the north wall of the north cross-wing a small single storey extension, probably designed as a garden feature, retains some features found on early C19 Cottage Orne estate houses in Marford and Rossett including blind ogee-arched Gothick window, Gothick lancet window to rear wall, blind arrow slit, and pebbledash render. Garden wall to the north west also retains some render, arrow slits, and blind triangular pedimented door.

Western elevation has no decorative enrichment, or the symmetry apparent to the other facades. Contained in a brick walled courtyard. Centrally placed chimney stack, single storey brick lean-to to right of stack. Late C19/early C20 wooden multipaned windows. New entrance under new triangular pediment constructed in the 1980's.
(Source; Cadw listing database) S Fielding RCAHMW 06/02/2006