Blast Engine house at Cefn Cribwr Ironworks

The blast engine house at Cefn Cribwr Ironworks is a Grade II listed building originally powered by a water wheel, which operated through a launder running across the east gable end. Constructed from local rubble sandstone, the building currently has no surviving roof. It features a rectangular shape with a central cross bob wall that supports the main beam of a 50 horsepower low-pressure water-powered blowing engine.

Inside, the chamber closest to the furnace includes a sunken section designed for a large water tank, along with an operational area that has doors on the north and south sides. The west gable end has a wide opening with a segmental brick arch that allowed pipes to extend to the furnace mouths. Additionally, there are four rectangular openings on the south side and a gable opening at the east end. Originally, two boilers were positioned on a brick base on the south side. A water culvert runs under the west end, likely fed by drainage from a drift adit at the rear, and it leads to a sump located on the south side of the engine house.