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Office and showroom of former Union Ironworks

A Grade II Listed Building in Caernarfon, Gwynedd

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Latitude: 53.1376 / 53°8'15"N

Longitude: -4.2728 / 4°16'21"W

OS Eastings: 248062

OS Northings: 362459

OS Grid: SH480624

Mapcode National: GBR 5J.66KB

Mapcode Global: WH43F.BDLJ

Entry Name: Office and showroom of former Union Ironworks

Listing Date: 3 May 2002

Last Amended: 3 May 2002

Grade: II

Source: Cadw

Source ID: 26547

Building Class: Industrial

Location: Fronting the road and at the SE end of Slate Quay.

County: Gwynedd

Town: Caernarfon

Community: Caernarfon

Community: Caernarfon

Built-Up Area: Caernarfon

Traditional County: Caernarfonshire

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Built as the Union Ironworks office and showroom in the third quarter of the C19 and shown on the 1889 Ordnance Survey. The Union Ironworks was founded by Owen Thomas in the early 1840s, who was joined by J.P. de Winton in partnership in 1854. The Thomas and de Winton families remained in control until 1892, after which it had a succession of owners before closure in 1902. As a foundry and engineering works it specialised in supplying marine engines and boilers, mainly to Merseyside shipbuilders, and also supplied the N Wales slate industry. By the second decade of the C20 the premises was occupied by the Kiwi Engineering Works.


A Gothic style office of 2 storeys and 3 bays, of yellow brick, the front wall now pebble-dashed front wall, decorative slate roof incorporating bands of light-grey slates, and yellow-brick ridge stacks, reduced on the L, to gabled rear projections which have a lower eaves line. The central doorway has plain square jambs with crocket capitals, moulded shouldered lintel with orbs to the spandrels and a cornice. Double panelled doors with overlight are framed by a recessed segmental-pointed brick arch. Above, the central bay has a narrow window carried above the eaves under a gablet with plain barge boards. The architrave has crocket capitals to a pointed arch, within which is an inner arch with tall 2-pane sash window. The outer bays have 3-light hipped bay windows in the lower storey, with detached ringed colonnettes and crocket capitals. The windows were boarded up at the time of inspection. The upper storey has narrower, shallow 3-light bay windows carried above the eaves under gablets on kneelers, with plain barge boards. The windows are 2-pane horned sashes framed by square mullions with crocket capitals in the R-hand bay, ringed colonnettes to the L-hand, and under pointed heads with quatrefoils in the tympana. Linked hood moulds have foliage stops.

The gable ends are yellow brick with blue-brick banding. The R gable end has, in the upper storey, two 2-pane sashes under segmental pointed heads that incorporate blank stone tympana. The L gable end is similar, but in the lower storey are blocked openings with stone lintels and segmental brick relieving arches. Added lean-tos are at the rear of the building.

Reasons for Listing

Listed (notwithstanding loss of original detail under later cladding) as a C19 works office retaining strong architectural character at a rare-surviving small urban foundry, and for its historical importance representing former industries on Slate Quay.

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