History

Llantrisant or Ynysmaerdy Colliery was established by the Powell Duffryn Steam Coal Company after World War I. It closed in 1942 following an underground explosion. It was constructed on the efficient modern model developed by the Powell Duffryn Company, with a single engine hall containing the main power equipment needed on the surface. The site is a particularly complete and impressive colliery complex, containing the engine hall, workshops and stores, ruined offices, a separate winding engine house, railway lines, tips, a long revetment wall, a reservoir, and an explosives store. It was associated with the planned housing estate at Ynysmaerdy.

The hay barn was formerly a winding engine house and may have housed additional power equipment, perhaps for electricity generation.

Exterior

A gabled structure of rubble sandstone with red brick dressings and a corrugated iron roof. It is built into sloping ground, with 2 storeys to the E and one to the W, and is 4 bays to front and back and 3 to the gable ends. The windows have segmental heads with deep, stepped surrounds and pronounced keystones, all in red brick, in typical Powell Duffryn house style. Red brick has also been used for the quoins, a deep eaves cornice, and a string course at the main floor level. The engine house faced the former shaft on the E side, where the bay L of centre has 2 smaller openings to the upper floor, one of which is offset, to carry winding cables, and 2 to the semi-basement level. The W elevation has large, equally placed windows. The gable ends have ventilator oculi with 4 stressed voussoirs and wooden louvres, central doorways flanked by windows, and single windows to the semi-basement. (The S gable end was overgrown with vegetation at the time of inspection.)

Interior

The interior has wrought iron roof trusses, concrete floors with steel beams and a core wall to support the winding engine. There are remains of plasterwork in the former engine room.

Reasons for Listing

Listed as a fine example of an inter-war winding engine house, and for group value in this unusually complete and impressive colliery complex.

External Links

• Cadwr Listing
• Wikidata Q29493547

External links are from the relevant listing authority and, where applicable, Wikidata. Wikidata IDs may be related buildings as well as this specific building. If you want to add or update a link, you will need to do so by editing the Wikidata entry.

Recommended Books

• 
  Suffolk: West: The Buildings of England (Pevsner Architectural Guides) (Pevsner Architectural Guides: Buildings of England)
• 
  Devon (Pevsner Buildings of England)
• 
  Staffordshire (Pevsner Architectural Guides: Buildings of England)
• 
  Historic Environment Law: Planning, Listed Buildings, Monuments, Conservation Areas and Objects, Supplement 2014
• 
  ENGLAND GUIDE TO POST WAR LISTED: A Guide to Post-war Listed Buildings
• 
  Northamptonshire: Buildings of England Series (Pevsner Architectural Guides) (Pevsner Architectural Guides: Buildings of England)