Monk's Barn, with walls, and former Cow House, Ashridge

Monk's Barn with walls, and former Cow House, Ashridge

A former tithe barn possibly dating to the 1480s, extended and converted into a coach house by Sir Jeffry Wyatville between 1813 and 1821, now used as office space. An attached former cow house, also by Wyatville, was incorporated into a teaching facility in 1972.

The original tithe barn has a timber frame with red brick infill, while the early 19th-century extension is constructed of red brick laid in Flemish bond with ashlar stone dressings, the whole under a roof covered in plain red clay tiles. The former cow house is constructed of red brick laid in English bond and has a slate roof covering.

The building is located in the stable court to the west of the house and overlooks the Monk's Garden to the south-east. It has a long linear plan aligned north-east to south-west, with the south-western half being the extension added by Wyatville. The former cow house, adjoining the south-west end, has an L-shaped plan consisting of north-east and north-west ranges, now partially subsumed by Lazell, a teaching facility built in the former cow yard in 1972. The part of Lazell forming a 20th-century extension to the former cow house does not have special interest and is not included in the listing.

The barn rises one and a half storeys under a steeply pitched roof with decorative bargeboards and finials at the gable ends, the upper sections of which have herringbone brickwork. The south-east elevation is defined by a covered walkway supported by an arcade of nineteen depressed arches with chamfered timber columns, which continues around the right return. The fenestration along this elevation consists of five pairs of 20th-century two-over-two pane horned sash windows set in recessed stone surrounds with segmental arch upper sections. At the far left is a wooden door with decorative strap hinges set in a stone surround with a depressed arch opening, likely created to provide access to the stable court. The mezzanine is lit by ten hipped dormer windows set wholly within the roof space, probably inserted when the barn was converted into a dormitory. A larger gabled dormer in the centre, dating to Wyatville's time, has trefoil-shaped bargeboards and wooden Y-tracery. Behind this rises a wooden octagonal lantern in a Gothic design with lancet windows on each face and miniature flying buttresses with cross gable finials, surmounted by a lead spire.

The north-west elevation, facing the stable court, has close studding and brick infill with a mid-rail and sole plate resting on a brick and stone plinth. Small windows with leaded lights have been inserted in some of the panels above the mid-rail. The mezzanine is lit by three gabled dormers with trefoil-shaped bargeboards wholly within the roof space, and a larger dormer in the same style as that already described. Directly beneath is a depressed arch carriage entrance infilled with glazing. The early 19th-century extension on the right-hand side is lit by four-light mullion and transom windows with arched upper sections in moulded stone surrounds. The end of this elevation is obscured by a glazed extension built 2001 to 2003 which links the barn to the former coach house to the north. At the other end, to the north-east, is a one-and-a-half storey red brick extension under a half hipped roof, added in the late 20th or early 21st century.

The former cow house, attached to the south-west gable end of the Monk's Barn, has been largely subsumed by Lazell, which has obscured most of its external elevations. The main entrance on the north-east side of the north-east range is a vertical plank door with decorative strap hinges set within a depressed arch stone surround embellished with egg-and-dart and foliate carving. This north-east elevation is formed by a crenellated and buttressed wall of knapped flint rubble which has a projecting gabled niche with ashlar stone dressings. The wall continues southwards to link up to the fernery, and is of red brick on the inner face, pierced by four wide depressed arch openings flanked by a smaller arch opening. The south-east elevation of the north-west range, visible from the small section of the former cow yard not infilled by Lazell, has three wide arched openings, formerly open but now glazed. The north-west elevation of this range has been re-fronted in modern brickwork and fenestration as part of Lazell.

Internally, the five-bay timber frame has a Queen post roof with jowled principal posts, crenellated tie beams and arch braces. The wind braces are between two butt purlins. The original south-west gable end of the tithe barn, now an internal wall, is close studded with a mid-rail and has been partially knocked through to make way for a door and staircase. Split collar beams have been added in recent years to strengthen the frame. A mezzanine has been inserted which is supported by the tie beams.

The south-west end, added by Wyatville in the early 19th century, has a king post roof with through purlins of sawn timbers. It has been converted for use as two-storey office space and has modern fittings, fixtures and finishings.

The north-east range of the former cow house, now the entrance hall of Lazell, is a single space with an inserted staircase and mezzanine at the south-east end dating to the 1970s. There are four exposed tie beams and the ceiling has been slightly lowered, which has created a canted ceiling. The north-west range is used as a corridor and has modern finishes. The 1970s fixtures and fittings are not of interest.

Adjoining the north-east corner of the barn is a crenellated wall of knapped flint rubble which runs northwards.