Construction World December 2015

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Building Contractors

Photos by Oliver Karstel

Alice Lane Phase II

The Alice Lane Precinct is in the heart of Sandton’s commercial hub at corner Fifth Street and Alice Lane. Alice Lane Phase II forms part of the greater precinct that entails the development of three new office towers that are linked by a central landscape piazza, pedestrian friendly and naturally green environment. Phase II is designed to relate to both the leaping horse design Phase I, and the future flagship tower Phase III, and stand on its own architectural merit. The offices are interconnected by a super basement with seven levels of parking which measure at an area of approximately 107 000 m 2 . Phase II is designed around an office anchor tenant with six office levels. The three structures might be joined at Project information • Company entering: WBHO Construction • Project start date: June 2012 • Project end date: November 2014 • Client: ABLAND • Project team: AP Da Costa • Main contractor: WBHO Construction • Principal agent: Paragon Architects • Project manager: ABLAND • Quantity surveyor: Quantity Cost • Consulting engineer: L&S Consulting • Project value: R289-million (excluding VAT)

the hip to each other by the piazza and the super basement, but they couldn’t be more different from each other: from the Angular Phase I to the Curvaceous Phase II to the soon to be completed Towering Phase III. Alice Lane Phase II’s design philosophy is exceptionally executed internally and exter- nally. Externally, the building’s dominant street-facing façade is softened by sweeping curves and tight-pinched curves as a notice- able departure from Phase I’s angular and faceted façades. The north and south elevations are glazed to introduce more natural light into the working spaces. The glazing specifica- tion comprises mainly platinum grey double glazed on all the main glass façades and single glazed on the ground floor. The ground floor extends to the exterior as a floating platform with spill out spaces for the canteen and auditorium. This inter- acts visually with the street. The relationship with the street is further explored with the idea of surfaces that peel away to provide vehicular and pedestrian access. Once the vegetation has matured, it will appear as a layered opening. The building has a central atrium with clerestory light to illuminate the work spaces. This atrium is formed as the two building forms enter inside from the piazza, allowing for an internal-external continuity of space. Each floor has bridge links connecting the common area to the floor plate.

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Alice Lane Phase II was awarded a 4-Star Green rating. The structure of the building is predominantly concrete. The main elec- trical supply consists of two sections. The critical section is backed up by a generator. The non-critical section powers items such as HVAC chillers, pumps and other non-areas not requiring generator backup. All other items are backed up via the generator. There is one generator which provides the emer- gency backup required for the building. The fire protection system does not expel water during testing; alterna- tively, water is directed back into storage tanks. Energy consumption is reduced to 165 kWh/m 2 /year and carbon emissions to 198 kg CO 2 /m 2 /year. A groundwater harvesting system is in place. The building is mechanically ventilated. Heating and cooling is provided by means of a four pipe central chilled water system using air cooled reversible hear pump chillers and four pipe in-ceiling fan coil units. Chillers placed on the roof make use of the compression cycle of refrigerants in order to transfer heat from the chilled water circuit to the atmosphere.

2 15 BEST PR O JECTS

CONSTRUCTION WORLD DECEMBER 2015