When spearheading the architectural design of I-CATs flagship green building, sited within the N4 Gateway Industrial Park in Pretoria, Earthworld Architects made it known the project should embrace its own sustainability mandate on three levels: ecological, economic and social. This also aligns to the crux of its client’s sustainable business.
I-CAT Environmental Solutions’ list of services includes environmental licensing, auditing, classification, compliance, monitoring and assessments. The new office and warehouse premises thus needed to encompass the environmental ethos of the company.
The new site was specifically chosen from a social perspective as it would reduce the transport impact for the majority of staff who reside in nearby Mamelodi; it is also close to the Mamelodi SOS Village, which is one of I-CAT’s social responsibility beneficiaries.
“We set out to create not just a building that would become a place where people work within an environmentally friendly designed structure, but one that would ultimately save money for the client,” says Rudie Botha, one of the architects on the project.
The climate and seasonal natural lighting inspired every aspect of Earthworld architects’ lines on paper. “Orientation brings mass light into the building when it counts, with vast glazed window shading and louvres for the days when the equinox dictates otherwise,” says Botha. “We specified as little artificial lighting as possible, and then only LEDs and CFLs.”
It was, however, the skin of the building that received the greatest attention for this was to set the tone of the building envelope and be the first line of defence against undesirable climatic impacts. Structurally, if Earthworld was to concentrate on dampening heat, maximising light, and factor in the three pillars of sustainability, it needed some drama.
Botha says the basic design is that of a grid building with two floors. Aiming for a rammed earth aesthetic, the architects steered away from traditionally muddy applications, instead selecting an unusually dark onyx brick from Corobrick, which, when recess-jointed with a visible white sand, a weaving pattern emerged. “It was a tricky application, yet it provided gravitas for the look and feel we were aiming for. Foreman Bob Kreder (fondly referred to as Bob the Builder), was a great asset in this process, truly one of the last and great Baumeisters,” says Botha.
A courtyard between the office and the warehouse on the cooler southern side addresses the social pillar of sustainability on a tangible scale as it provides comfort for employees. A pergola feature under which a water feature trickles into a Koi pond that doubles as a bird bar invites contemplation, shared lunches and communal interactions.
For the client, an unexpected surprise is a roof garden that not only provides insulation and contributes to the view, but also serves to collect rainwater, which, along with other harvested water from the building’s roofs, is fed into a 40 000-litre water tank buried beneath the courtyard. The tank is connected to a water filtration system that supplies the building with clean filtered water, the technology of which was developed by the client, I-CAT. Botha commends I-CAT for its innovation: “How better to showcase one of your core business systems and prove what can be achieved in the process of purification?”
It’s a similar situation with the energy usage and performance, which are major determinants of sustainable performance. The premises remain connected to the municipal electricity grid but solar panels and PVs are the main source of power.
The solar PV system on the roof was designed and installed by Holms and Friends. A 50kWp grid-tied system feeds into the office grid, and will generate approximately 87 500kWh/annum. The 200 modules manufactured by SolarWorld come with a 30-year linear performance guarantee.
Henning Holm, from Holms and Friends, says payback is around six years. Levelised Cost of Electricity equates to R0.53/kWh with maintenance, component replacement and VAT inclusive, but not including finance costs.
In almost all respects there were no problems encountered in building I-CAT’s flagship, which, from start to finish took barely 10 months. The only cause for concern lay in the hands of project manager Post, who says there was an enormous amount of clay on-site.
Speaking in-house is Hendrieka Raubenheimer, interior architect at Earthworld. Her task was to ensure the matrix of the sustainability pillars continued indoors, and she wanted to keep it simple.
“I am fond of looking at the lifecycle of the product, not just its end use, but how much energy was consumed in the development. The choices of the interior must take into account form and function, and that explains why I was unable to resist plywood furniture flat packs from Raw Studios for entire bulk furniture items throughout the building. Easy to assemble on-site, the precise and energy efficient manufacturing processes ticked all my sustainability boxes, including economic value.”
Environmentally sustainable considerations further included low VOC recyclable carpets, greenery and recycling bins in the kitchens. Ecophon suspended ceilings dampen sound in the meeting areas and contribute to the creation of a pleasant working environment. “It is a light and tranquil setting,” says Raubenheimer.
Botha points out when it comes to sustainability, the lines do blur between interior and exterior architecture, which is what ultimately creates the “natural shell of a building”.
The shell, in the case of I-CAT’s building, is where the romance happens, in Botha’s opinion. “The building’s roof overhang, combined with striking round-shaped steel columns, hide small LED lights that shine down onto the concrete window sill at night. The shimmer is impossible to ignore. It adds a rhythm to the elevation,” says Botha. During the day the drama is focused around the massive brick facade that forms a network of bricks that dissolve into punched window openings.
By Kerry Dimmer.
For the full article, see earthworks magazine Issue 30, February-March 2016.