Upper Dens Mills, Princes Street, Dundee

Upper Dens Mills is a large, 3-storey and attic, 10-bay fireproof mill built in 1833 by Umpherston and Kerr, located on Princes Street, Dundee. The complex was extended to the west in 1850 by Peter Carmichael with Randolph, Elliot and Co., adding a further 10 bays with a basement, a third floor, and a cast-iron attic, as well as a second engine house. The building is primarily constructed of rubble with ashlar margins, and features a slate mansard roof.

The south elevation presents as a 4-storey and attic, 23-bay mill with blocked basement windows in the western section. The slightly advanced twin central engine houses rise through three storeys, fronted by pairs of tripartite windows framed by Doric pilasters and segmental arches. A cast-iron tie-plate is visible at first floor level, with a cornice at second floor level and three windows at third floor level. A main cornice runs along the top.

The east elevation has a 3-bay gable facing the mill, with two windows on each floor, a central bay blank and housing wall boxes. Three oculi are positioned above the main cornice. The mansard roof is topped with cast-iron urns. A projecting square-plan stair tower, with a door and windows facing east, is roundheaded at the fourth floor. Blind windows are present on the north side, and the blank east elevation. A tower beyond the areas level was added in 1850, featuring roundels on its four sides. A circular cast-iron bellcote, supported by six Doric columns linked by wrought-iron railings, sits atop a conical spire, which is covered in fishscale slates and topped with an iron finial.

The north elevation consists of 24 bays, with the central engine houses accessed through two doors, the east with a cast-iron lintel and the west with a large fan light. Four blocked windows are situated above the doors, and there are three windows at the third floor level. The engine house is flanked by tall, projecting soil chutes rising from cast-iron brackets at first floor level. A skewed, 3-bay western gable has blind windows, and three oculi are situated over the main cornice. The mansard roof is adorned with cast-iron urn finials.

The original windows were 56-pane, but are now 12-pane sash and case.

The interior is fireproof and includes two rows of cast-iron columns supporting brick arches carried on cast-iron beams, which are tensioned by wrought-iron ties. The columns are now encased in plasterboard, but the brick arches and wrought-iron ties form the ceilings of most rooms. Original spiral stairs are located at the ends of the mill, and a new stair has been inserted within the engine house. The engine house features a painted brick arched ceiling supported by cast-iron beams with later steel supports. The tripartite windows have fine moulded soffits. The Gothic cast-iron mansard roof is notable, possibly the first of its kind in Dundee, with a small section visible near the lift. The basement has a high arched ceiling supported by brick piers.