| (Article Published in Architectural Journal)
UNIVERSITY OF FORT HARE: NEW AUDITORIA AND TEACHING COMPLEX: EAST LONDON CAMPUS
 
Architects and Principal Agents: Ngonyama Okpanum Associates
In association with Native Architecture
Consulting Civil / Structural Engineers: HSC Consulting
Consulting Mech. / Electrical Engineers: Carifro Consulting Engineers
Quantity Surveyors: Pulana Baxter and Associates
Main Contractor: Grinaker - LTA Building Cape
Pre-cast Specialist: Wintec Innovation (Pty) Ltd
Background
The historically renowned University of Fort Hare, situated in Alice has in recent times focused on developing its East London campus in order to meet a much needed demand for higher education in the city. To this end, the forward thinking Vice Chancellor and the University Strategic Development Team commissioned the architects to produce a Strategic Development Framework Plan that addressed the integration of ‘town and gown’ underpinned by the sustainability imperative. Because the campus in East London is undergoing a rapid developmental phase, planning to upgrade from 3 000 to 10 000 students within a few years, it became apparent that any new facility would require maximum design flexibility to accommodate various faculties as the different departments moved through the available space as it becomes available. In this context the brief for the accommodation requirements had to be generic.
The architects developed a ‘pattern language’ to regulate the design intent; this, inter alia, included; all floors to be accessible for services, all buildings to be oriented with long facades facing north, limited air conditioning for apparatus only, naturally ventilated spaces, natural daylighting, locally sourced materials, light weight construction, etc. Also, alternative energy sources and rain water harvesting where factored into the equation.
The site available for the first new building under this regime is situated within the business zone and in this context required that all new development had to be over at least two floors of parking resulting in an 8.4 by 8.4 column grid. Unfortunately the Department of Education funding norms are not predicated on inner city development requiring an expensive parking solution; this together with other considerations severely compromised the available budget resulting in the projection of the column grid up into the teaching facility without the luxury of costly transfer beams.
Design Response
In planning, the complex is bounded on the north and south sides by wide streets; the primary response was to place three wings running east west, in downward cascade from the south towards the north allowing solar exposure to each wing reducing the winter shadow. Each wing is in turn penetrated by a pedestrian concourse which is vertically connected by a lift in the south wing and a series of double acting staircases at the intersection of each wing. This concourse starts on the street at parking level on the south side and spills out onto the street at second floor which is at grade on the north street. In this way the concourse becomes a pedestrian arcade of the city.
In section, the wings are single banked with pedestrian access along the south façade and teaching space lit and cross ventilated to the north. The structural floor system is cantilevered to both the north and south off the 8.4m column grid to provide a typical wing of 13.2m in overall width with a space of 3.6m between the buildings and 6m between internal spaces. The section also informs the ventilation system. The external façade to the south walkway is faced with a permeable mesh screen which serves to break wind and driving rain. Immediately inside of this screen there is a vertical planting screen with timber planter boxes at each floor which are irrigated with harvested rainwater; this serves to provide evaporative cooling and oxygenation of natural air which is drawn into the building from the cooler side of the building, it also provides a ‘handrail’ to the walkway. Air is then drawn into the Wintec Ventilated Access Floor through special floor mounted diffusers by virtue of displacement ventilation within the interior space.
The north façade is double skinned and is ventilated at the roof apex. This façade is made up of U-shaped in plan black pre-cast concrete panels glazed across the U to form a vertical flu. This combination alternates with an internal glazed timber façade which is opposite a flush glazed façade spanning between the pre-cast panels. In this way another vertical flu is formed between the two glazed facades. Also, the internal reveal of the pre-cast panels is splayed and painted white; this together with a vertical reflective Venetian blind within the flu space controls bounced light into the interior. The ventilation system is powered by solar energy through buoyancy induced in the ventilated stack façade and also by wind induced pressure differences generated at the aerofoil section covering the continuous apex roof slot.
The ventilated access floor is a new concept which provides a floor plate with access from top and bottom, a plenum for services and ventilation all within a structural depth of 525 mm. The floor is finished on both faces with pre-cast concrete floor / ceiling tiles which provide a heat sink and are fitted with service access points for power and lighting. The all up mass of this floor is 45% less than an equivalent in-situ access floor which would be about 850 mm deep. In this way the embodied energy is dramatically reduced by bringing less material to site and the floor may be deconstructed and built into another project at the end of the building life cycle.
The choice of laminated Saligna for all joinery was informed by the need to not import exotic hardwoods or aluminium extrusions. This timber is locally sourced and after lamination is still cheaper than Meranti.
Fort Hare, in keeping with its tradition, has not been afraid to embrace the sustainability issue in order to demonstrate its commitment to progress.
Al Stratford Pr. Arch. M I Arch.
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