Former Blast Engine Houses at Tondu Ironworks

Of coursed roughly dressed ironstone with tooled ashlar dressings and some yellow brick dressings; rubble basement; formerly a Welsh slate roof, now roofless. Three storeys and basement; plan of larger rectangular gabled engine house with added smaller setback gabled wing, the 2nd engine house; some substantial later alterations. Frontage right has at apex a blind semi-circular arch with blind oculus; below on 2 floors are 2 bays of round headed windows with tooled ashlar surrounds, imposts, voussoirs and keystone, all with later and broken glazing, and matching blocked central former doorway arch of 2 orders; tooled quoins; inserted round headed red brick arch on left return wall. Side right elevation has 2 round arched windows with vermiculated relief keystone, tooled imposts, surround, and sill, on 3 storeys, plus one brick window added at first floor level; also various further openings, some blocked. Two bay gable end rear has similar windows at each level and at basement level a wide blocked semicircular arch with vermiculated keystone; inserted door right.

Left wing frontage has a gable oculus at apex; at first floor a large segmental arched window right with yellow brick voussoirs and tooled ashlar surround and wide segmental arched yellow brick doorway to ground floor now partly blocked; exposed corework front left suggests former structure attached here; tooled quoins to right. Side elevation left has similar segmental arched windows, 2 on each floor - larger below, replaced glazing. Rear has apex oculus, blocked similar doorway on ground floor with window above, the voussoirs replaced by concrete lintel.

Interior of primary building is open to roof and has trusses of a 5 bay roof structure in place; below on the end walls are the large corbels which held the two spring beams supporting the engine which used to drive a Boulton and Watt type blast pump; 2 smaller in side wall right formerly supporting floor at this level; metal track remains left; steam pipe in mid side wall right; furnaces were behind semi-circular arch in gable end. Floor of concrete inserted later, probably associated with steam turbines etc installed following the end of iron making; area of floor open to basement, reputedly still housing electrical equipment and rendered foundation structure possibly the foundation of the beam engine. Walls were originally lime rendered, later partly replaced by cement. Second house is of 2 bays with a single roof truss; blocked round headed openings to primary structure precede this building, and other now blocked openings were later created to join the two; later brick fireplace built across corner; later concrete suspended floor, but evidence for early engine supports and fittings may exist below; never rendered just limewashed.