Construction World February 2016

PROJECTS AND CONTRACTS

SUSTAINABLE

CAMPUS The challenges of a

The new sustainable I-CAT campus, in the N4 Gateway Park in Pretoria, was designed by Earthworld Archi- tects and Interiors, and completed by MBA North member, J.C. van der Linde & Venter Projects, in August 2015. Pieter Venter, J.C. van der Linde & Venter Projects' contracts director, says Earthworld Architects & Interiors concentrated on maximum sustainability in the design of the I-CAT campus. For example, among the environmental- ly-friendly features that had to be provided by the contractors was a rainwater harvesting system, incorporating a 50 000 litres reser- voir, sunk beneath part of the structural pergola-covered courtyard outside the main building. “The reservoir will collect all the has completed a multi- million rand contract for the construction of new green corporate offices and a warehouse for I-CAT Environmental Solutions. > Leading Pretoria building contractors, J.C. van der Linde & Venter Projects,

A roof overhang over the north-facing windows of the I-CAT office block shades the building during summer and partially during winter.

rainwater from the combined roof area, which covers almost 1 500 square metres. This water will be filtered and reused to flush toilets and for landscaping purposes. We also had to install solar water heaters that convert solar radiation into thermal energy, and solar powered heat pumps as part of Earthworld's focus on sustainability,” Venter stated. He said some of the unusual features that had to be provided – and the challenges faced – by J.C. van der Linde & Venter Projects for the project included: • The excessively clay soil had to be cut and filled with suitable material before work could start on the foundations; • The design of the office building called for top quality ('Degree 1') off-shutter concrete on all the facades which meant that the contractors had to employ special formwork to produce a smooth off-shutter finish; • Special recessed patterns had to be provided in the facebrick façade of the new building; • The installation of a special interior floating concrete staircase with structural steel frame, close to the reception area, called for in-situ casting of the top quality raw concrete stairs specified in the design; • The provision of the structural steel pergola in the courtyard called for the supporting timber poles to be installed at specific angles instead of traditional upright installation; • Interior finishing, apart from the top quality off-shutter concrete, required extensive installation of special eco- friendly spruce plywood for the office partitions and ceilings; and • The provision of an intricate, external curved spiral structural staircase in the courtyard leading to the roof garden.

“J.C. van der Linde & Venter Projects also had to contend with quite a few design changes during the course of the 10-month contract,” Hermann Post, J.C. van der Linde & Venter projects associate, commented. Earthworld Architects and Interiors' Rudie Botha says the completion of the new I-CAT campus realised an ambition to achieve abso- lute minimal impact on the environment. Factors such as the local climate's effect on energy consumption, the use of natural light and shading devices on applicable facades, as well as the office staff's thermal, visual, and acoustical comfort, as well as air quality were just some of many factors taken into account. “In summer, the building is ventilated nocturnally and during the early hours of the morning, allowing the temperature inside to drop. When heat builds up inside later in the day, the windows at the top of the building automatically open to allow hot built-up air to escape. Interior temperature is furthermore controlled by an automatic air conditioning system, driven by solar power. “The use of the light-weight but elegant spruce plywood office partitions provides flexibility as the open plan layout can be divided into smaller sections if needed. The warehouse also has a column-free design, with supporting columns only along its perim- eter, also allowing for interior changes to suit future needs.” Botha continues: “On the north-facing windows, a roof overhang shades the building completely during summer and partially during winter. Vertical fins on the east-facing windows deflect early morning radiation during the summer and the afternoon sun on south facing windows. The use of windows on the facebrick façade, which faces east and west, was restricted: also for thermal reasons.

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A structural steel pergola in the campus courtyard is supported by timber poles installed at specific angles.

CONSTRUCTION WORLD FEBRUARY 2016