Mechanical and Aerospace Engineering, Ashby Building, Stranmillis Road, Belfast, Northern Ireland, BT9 5AH

The Ashby Building (originally the Ashby Institute of Engineering) is a large-scale Modernist university complex designed by Manchester architects Cruickshank and Seward, with W.A. Gibbon as overseeing partner, and constructed between 1960 and 1965. It was officially opened on 7th May 1965 by Sir Eric Ashby, Vice Chancellor of Queen's University Belfast from 1950 to 1959 and later Chancellor from 1970 to 1983, after whom the building is named. The main contractor was F.B. McKee and Co. of Shore Road, Belfast. The total project cost was £2.5 million. It remains in use as a university building and is one of the best examples of a large-scale Modernist in-situ concrete building in Northern Ireland, and a landmark in south Belfast.

The complex sits at the junction of Stranmillis Road and Chlorine Gardens, where the ground falls steeply to the west. It comprises three distinct elements connected by glazed link buildings: an eleven-storey tower block, a three-storey square courtyard laboratory block, and a two-storey lecture theatre block with a two-storey glazed entrance link. The tower and laboratory blocks are connected by a two-storey glazed link at ground and first floor levels. The building is entered from Stranmillis Road to the east via a first floor level glazed entrance link, with secondary accesses on the north elevations of the tower and laboratory blocks at ground level. A large retaining wall and sunken courtyard with car park run along the Stranmillis Road boundary. The surrounding area consists largely of 19th-century red-brick residential and commercial buildings. The building lies approximately 0.5 km south of the Lanyon Building, Queen's University Belfast, and within a small cluster of higher education buildings, including the David Keir Building on the adjacent site to the north and the new School of Biological Sciences on the former site of the Science Library in Chlorine Gardens.

The building is uncompromisingly Modernist in style. All elements are constructed of reinforced concrete, which functions as both a structural and architectural medium — no attempt was made to conceal the frame or walls with veneers of other materials. The concrete was made using locally quarried Glenarm limestone and white cement, producing bright white surfaces that reflect changes in light. As Gibbon wrote shortly before opening, hardwood was used for window frames, ventilation louvres and the soffits of the laboratory roof to add warmth and colour to the facades, with the tonal contrast playing an important aesthetic role. Further relief is provided by Mourne granite panels facing the ground floor walls of the tower.

The entrance link and lecture theatre block have flat roofs with bituminous or single-ply membrane covering, concealed rainwater goods of possibly cast metal or uPVC, in-situ reinforced concrete ribbed-pattern walls, and replacement powder-coated aluminium double-glazed windows. On the east elevation facing Stranmillis Road, the entrance screen has brown and black powder-coated aluminium sliding double doors and full-height glazed panels beneath a cantilevered flat roof with a plain deep fascia painted white, white powder-coated aluminium parapet cladding, and galvanised metal tube safety railings to the roof perimeter. The soffit of the entrance screen is formed of smooth painted fibreboard panels with circular recessed light fittings. Metal lettering attached to the entrance fascia reads "Ashby Building". The lecture theatre block presents a blank ribbed in-situ concrete wall to the east, divided into four similarly sized sections by horizontal recesses, with a matching parapet and railings. The west rear elevation of the lecture theatre block is similarly finished, with horizontal recesses dividing the facade into four sections; it has a horizontal rectangular strip opening with louvres at the upper section, two small horizontal window openings at upper ground floor level, and at ground level a large recessed panel containing louvred panels and doors. To the right of this is a natural stone wall extending into the sloped landscaping, with a more recent natural stone wall erected at right angles to screen a lean-to shed. Three equally sized square window openings sit to the left.

The north side elevation of the glazed entrance link consists of two storeys of floor-to-ceiling windows running the full length of the link, with continuous horizontal in-situ concrete bands at floor and roof level. Windows have transoms at every column and at the midpoints between columns, and are metal-framed with replacement double glazing. The south side elevation follows the same arrangement. On the south side, the lecture theatre block abuts the central section of the entrance link, and a short gap between the east wall of the theatre block and the Stranmillis Road boundary is bridged by the in-situ concrete floor of the entrance link, supported on two in-situ concrete circular multi-faceted structural columns painted white. The undercroft beneath the bridge is finished in concrete paviors, which continue on a ramp around the boundary of the theatre block. The south facade of the lecture theatre block has a ribbed in-situ concrete wall divided into four sections by horizontal recesses, with a vertical strip opening with louvres at the far left of the upper section.

The tower block has a flat roof with bituminous or single-ply membrane covering, concealed rainwater goods, in-situ reinforced concrete walls in both ribbed pattern and diamond formation pattern, and replacement powder-coated aluminium curtain walling. The east front elevation presents a large ten-storey facade of continuous horizontal bands of windows — nineteen window openings per floor — with deep continuous horizontal bands of in-situ concrete at each floor and ceiling level. Each window is subdivided by a narrow continuous concrete pilaster running the full height of the facade from parapet to first floor plinth. The windows are square-headed in landscape profile, with replacement powder-coated aluminium double glazing. At ground level the wall is recessed behind seven large in-situ concrete circular multi-faceted structural columns painted white, with the wall surface faced in square granite panels. There are arrow-slit openings with powder-coated aluminium windows and two large louvred openings to the left; at the right corner at ground level there is a full-height glazed screen. To the left of the ten-storey window facade is a vertical band of curtain walling extending from first floor level to roof, enclosing the main staircase core, with a powder-coated aluminium frame and replacement double glazing. To the left of this curtain wall is a large panel of diamond formation patterned in-situ concrete extending the full height of the tower — a striking and distinctive feature of the building. The roof has a slim concrete coping to the parapet and galvanised metal tube safety railings. At roof level on the eleventh floor there is a large rectangular flat-roofed plant building, single storey with a two-storey tower, constructed in ribbed in-situ concrete.

The west rear elevation of the tower has a large panel of diamond formation patterned in-situ concrete at the right corner and a large panel of in-situ concrete with exposed shuttering in the béton brut manner at the left corner, with horizontal recesses at regular intervals, both extending the full height of the tower. The main section of the west elevation presents a ten-storey facade of continuous horizontal bands of windows and concrete walling, similar to the east facade with twenty window openings per floor, stopping at first floor level. At ground level the wall is recessed behind in-situ concrete circular columns and faced in square granite panels matching the east elevation, with horizontal openings centred between the columns fitted with powder-coated aluminium windows. A two-storey glazed link connecting the tower block to the laboratory block abuts the west elevation at first and ground floor levels.

The north side elevation of the tower has a large vertical band of curtain walling from ground to roof level covering more than half the width of the elevation, enclosing the second staircase core, with powder-coated aluminium framing and double glazing. The glazing is subdivided into regular square sections of fixed glazing, with louvred sections at floor levels on the far left. A large vertical panel of diamond formation patterned in-situ concrete occupies the left corner from first floor level to roof level, with curtain walling at ground level beneath it. The south elevation is an eleven-storey facade of continuous horizontal bands of windows, similar to the east and west facades, with five window openings per floor. At ground level the glazing extends to full floor height with louvred infill panels at the bottom.

The laboratory block has a flat roof with bituminous or single-ply membrane covering, concealed rainwater goods, in-situ reinforced concrete ribbed walls, and replacement powder-coated aluminium double-glazed windows. The east elevation presents two continuous horizontal bands of strip windows at ground and first floor level, with a deep continuous horizontal band of ribbed in-situ concrete at first floor level. A two-storey glazed link connecting the laboratory block to the tower block abuts the right-hand side of this facade. A large overhanging flat roof with deep fascia sits at roof level. The windows are subdivided with narrow vertical infill panels; at first floor level they are divided into regular sections by transoms and alternate between fixed pane windows and windows subdivided horizontally into three sections with opening lights. At ground level to the left of the glazed link the windows are deeper, with some infill panels at the centre, a full-height metal roller door in the centre, and a set of glazed double doors to the left. The roof has a slim concrete coping and galvanised metal tube safety railings, and there are several plant buildings at roof level: a square-plan flat-roofed building in ribbed in-situ concrete, and a large circular drum with a tall circular flue constructed in shuttered concrete, painted white. This drum and chimney arrangement on the roof is in the manner of Le Corbusier and is one of the most characterful features of the building.

The west elevation of the laboratory block has two continuous horizontal bands of strip windows at ground and first floor level and two deep continuous horizontal bands of ribbed in-situ concrete at floor and ceiling levels. First floor windows match the east elevation. At ground level the windows are clerestory, with some louvred infill panels at high level and small horizontal window openings at lower level. The north elevation has a band of horizontal strip windows at first floor level with a horizontal band of ribbed in-situ concrete below, and is otherwise detailed similarly to the other elevations. At ground level to the left is a band of clerestory windows and a section of full-height windows with infill panels; in the centre is a large square-headed opening providing vehicular access to the courtyard, to the right of which is a glazed screen enclosing the stairwell with glazed double doors; to the right-hand corner is a further section of clerestory glazing, with a stairwell leading to the basement and clerestory glazing. The south elevation is similar to the west elevation and also has a stairwell leading to the basement with clerestory glazing.

The courtyard elevations of the laboratory block follow the same general approach as the external elevations, with continuous bands of horizontal strip windows and ribbed in-situ concrete on two levels. Windows combine larger horizontal strips of glazing serving the laboratories and smaller horizontal strips lighting the corridors. A continuous horizontal ventilation grille runs at first floor level along three sides of the courtyard. At ground level there are several large openings fitted with roller shutters to service laboratory areas.

Internally, the building retains the 20th-century Rationalist character of its design virtually intact, despite some modernisation of materials and the addition of fire safety screens. The staircases are of particular note. The main stair is constructed in reinforced concrete with terrazzo treads and slender steel balustrades, enclosed to one side by a vast curtain wall running the entire length of the building.

The design philosophy behind the internal layout was one of flexibility. Gibbon wrote that in a world where total scientific knowledge was doubling every fifteen years, the building had to allow for frequent and quite radical changes of layout and services. Partition walls could be moved, services re-routed or augmented, and brought to any point within the building.

The site boundary on Stranmillis Road and at the south-east corner is enclosed by original painted steel railings consisting of slim rectangular-section uprights on horizontal rails, supported by posts mounted on a low concrete wall, with a gap at the main entrance on Stranmillis Road where the entrance area is paved in granite flags. The site is bounded to the east and west by a large in-situ concrete retaining wall, with a lower-level courtyard and car park facing the tower block to the east. Hardstanding around the site is generally tarmacadam with some concrete paving in the lower courtyard. In-situ concrete raised planters are incorporated into the hard landscaping around the buildings. A bank of soft landscaping with a lawned area and mature trees lies to the south of the entrance link and lecture theatre block, with a raised car park area immediately to the west. An original small plant building is attached to the west retaining wall, square in plan with ribbed in-situ concrete walls and a circular concrete drum to the roof.

The low-lying nature of the site — a consequence of centuries of excavation of the old sandpit that previously occupied the plot — allowed the grounds to be laid out as a sunken garden, the soft landscaping originally providing an effective contrast to the bright hardness of the concrete structures. These grounds have seen the most change over the years, with much of their original extent given over to car parking, and the suburban aspect of Cloreen Park to the west disappearing entirely with the construction of the two large brick blocks of the Northern Ireland Technology Centre in 1989 and the Queen's Sonic Arts Research Centre in 2004.

Historically, the building emerged from the rapid post-war expansion of Queen's University Belfast. The inter-war period had already seen the campus grow beyond the original 1840s college building, with the Faculty of Agriculture on Elmwood Avenue opening in 1926 to 1928 and the Whitla Hall begun in 1939, the latter completed after the war in 1949. By the early 1950s the university had acquired a large swathe of land between the Malone and Stranmillis Roads and, in conjunction with Belfast Corporation, commenced what was then its largest building project, the David Keir Building for the Faculty of Applied Sciences, opened in 1959. Within a year, a similarly ambitious scheme was under way on the plot immediately to the south. The Ashby Institute was initiated by the Joint Authority for Higher Technological Studies, a partnership between the university and Belfast Corporation, and was designed to accommodate the Departments of Electrical Engineering, Mechanical Engineering and Engineering Mathematics. Where the Keir adopted a somewhat outmoded aesthetic reminiscent of the 1930s, the Ashby was its complete opposite in architectural character.

Externally the building has seen little alteration since construction, but underwent a major £26 million refurbishment between 2010 and 2013, overseen by Kennedy FitzGerald Architects. This was carried out in three stages: the first phase in 2010 covered the lower floors and replacement plant room; the second phase in 2011 to 2012 addressed the fifth and seventh to ninth floors; and the final phase, completed in April 2013, covered the first to fourth and sixth floors.