The Croft Barn is situated approximately one mile north of White Castle on land originally part of the Great Trerhew estate (see Great Trerhew Barn project). It is listed Grade II* as an important timber-framed barn, first recorded by Fox and Raglan (Monmouthshire Houses Part I, p62-65), with exceptionally fine carpentry. The original barn was probably wholly timber-framed and the stone gables added later. The west gable has subsequently been rebuilt and the barn on this side shortened. The building illustrates a late development in cruck-truss tradition, where crucks alternate with framed trusses in the same building. On the north side the timber panels are largely exposed and include, below eaves, rare-surviving oak stave and lattice panels with the lower panels clad by horizontal weatherboarding.
The present owners, White Castle Vineyard, first approached the Trust for help in conserving this fine sixteenth century barn in 2011. The Trust commissioned a Condition Survey by Morgan and Horowskyj Architects, Abergavenny, and dendrochronological dating of the timber was carried out, funded by the Royal Commission on Ancient and Historic Monuments of Wales. Seven samples were taken from various elements of the barn and one timber with retained sapwood was found to have been felled in spring 1581, with supporting date range for two other samples. The study by the Oxford Dendrochronology Laboratory (report 2012/49) concludes that the barn was constructed in 1581.
The Trust has worked with the owners to secure funds from CADW and the Heritage Lottery Fund to conserve this important building and to use it as a learning centre for wine growing skills and heritage activities.