Old Castle Iron and Tinplate works operated from 1866 to 1957. Developed in two main phases, to form two works in tandem. The first of these was developed 1866-68 and no longer survives. A second works was built alongside the first in the period 1905-1913, and it is this which survives virtually intact, with some later alterations, mainly associated with the subsequent use of the site as an engineering and fabricating firm. Listed at Grade II* as a remarkably well-preserved Tinhouse, one of only 2 known to retain original tinning bays. The Tinhouse forms an integral part of a virtually complete early C20 tin-plate works, one of a very few to survive in the former heartland of the industry and is of special interest by virtue of the completeness of its survival, and as a rare example of an industrial complex of transitional constructional type, in which the use of steel frame and brick alongside masonry structures is of particular significance.

The original layout survives virtually intact: 6 tinning bays to each side, each with heavy iron lintel carrying segmentally vaulted brick ceiling with central wide tapering rectangular chimney (truncated at roof level); each bay has small blocked window to either side of hearth; one bay retains parts of original pully mechanism. 2 bays in S range have been damaged by removal of chimneys; 3 bays to N partially bricked-up. There is a blocked segmentally arched doorway in centre of W wall which formerly led to the Hot Rolling Mill; sliding doors in E wall lead to Assorting Room. Light steel truss roof.

The Tinhouse is sited between the Hot Rolling Mill and the Assorting Room towards the E end of the site. Externally it is partially concealed by a later office range to the N, and by various corrugated iron sheds to the S. Its constructional form, however is clear: rough rubble walling, with corrugated asbestos and slate to roof which has distinctive ridge clerestory. 5 blocked segmentally arched openings with yellow brick heads beneath eaves in N-facing elevation; similar blocked openings in 2 tiers to S. Office range (c1960) to N is brick, but is built in what appears to be the rubble plinth of an earlier building.

Source: Cadw listed building database (Ref: 18657)

Photographed during aerial reconnaissance by RCAHMW on 20th June 2008.