When your business is water pumping, filtration and treatment, it makes sense to use your building as a showcase for your work. The new head office in the Grundfos complex in Germiston, Erkurhuleni is an example of how a building can achieve total water sustainability.

Located at the junction of the N12 and R24 highways, and providing a workspace for between 200 and 250 people, the Grundfos office complex is both a showcase for the business and a green story in action.

 

Owned and developed by Growthpoint, the complex consists of an office block and a warehouse. The office block is currently pursuing a green star certification through the Green Star SA Office V1 rating scheme. The main draw card is a rainwater harvesting and treatment plant that provides clean drinking water throughout the complex, with virtually no need for municipal top-up.

 

Waterways

“The building is located in a high rainwater catchment area and will be able to catch large amounts of rain and store it,” says Yovka Raytcheva-Schaap, environmentally sustainable design consultant for Aurecon, which managed and co-ordinated the project. “Because of this, it is expected that the building’s domestic water demand will be covered by the rainwater available on site except during the winter months of June, July and August.”

The rainwater is collected from the roofs of the office building and warehouse, and from the paved and permeable areas, before it is channelled to an underground attenuation tank. The total catchment area is 19 934m2 and the tank holds 1500m3.

The filtration plant is showcased in the atrium of the office building and treats water to drinking quality. Harvested water reaches the offices and warehouse through a single piped system that is also used for municipal water. The water has attained South African National Standards for drinking water as specified in SANS241.

Harvested water is passed through a direct floc filtration (DFF) process. Chemical dosing pre-conditions the water for carbon filtration and disinfection.

Water is drawn from a borehole and the municipal supply in the dry months. It will switch firstly to borehole water before tapping into the grid.

Because of this, the project team considers that the water supply system implemented in the Grundfos facility by far exceeds the aim of the Wat-01 credit, which is to encourage and recognise designs that reduce potable water consumption by building occupants.

Since the design of the water harvesting system incorporates Grundfos technology, Grundfos general manager Jonathan Hamp-Adams calls it “taking our own medicine”.

 

Layered sustainability

The design brief for the office space was to create a “typical Grundfos building with a South African feel,” says Hamp-Adams. It had to be a space that could showcase the company’s pumps in action and aim to achieve an official Green Star SA rating.
Architect Riaan Swart from Empowered Spaces says the result of their brief is a clean, modern building. The envelope consists of insulated concrete roofs, brick walls and large swathes of high-performance glazing through interwoven insulated glazed spandrel panels on the south and west facades.

Another major focus for the project was energy efficiency and green design. Natural light penetrates the offices via a large central atrium lit by monitors to the south and north. Energy efficient compact fluorescent lighting and LED lights are used throughout the building in a layout that ensures minimal fixtures are required to maintain sufficient lighting levels. The building is divided into zones and the fixtures in each are connected to motion sensors, allowing lights to turn off when spaces are not occupied. There is also a manual override.

“The motion sensors were fitted on a master and slave system,” says Botha. “What normally happens is that an engineer will design a sensor that will cover four or five light fittings, but we created a master and slave configuration, with one light fitting with several other slaves attached to it. This ensures a complete flexible lighting system.”

The lighting was designed to reduce power to as little as 1.5W per 100 lux for 95% of the usable area, which is an achievement since there are a few small office spaces that proves to be challenging,” says Louwna van Wyk, junior environmentally sustainable design consultant at Aurecon. “The open plan design also contributes to better light and air distribution,” says Van Wyk.

Maximum use was also made of daylight. “The building’s design enables the harvesting of natural daylight but at the same time glare is controlled through external fixed shading and internal blinds where necessary,” says Rathcheva-Schaap.

The feel-good environment goes further than the maximisation of light and space. All paints, carpets, adhesives and sealants are of products that contain low volatile organic compounds, and the specified composite wood has low formaldehyde emission levels.

Fresh air is provided at a rate of 12.5L/s/p, exceeding minimum legislator requirement – this is done via a heating ventilation and air-conditioning system comprised of a series of DX split type air-conditioning units.

Green details are found in features throughout the complex – from the canteen with a grease trap to waterless urinals, solar- and wind-generated power, and a xeriscape garden. Recycling policies are standard.

The building process also considered a sustainable approach. “We started by demolishing the building on the site and reused it as crushed rubble. We created a double volume entrance space and an atrium with an indoor water feature alters the space in ways that one wouldn’t expect of an industrial office space,” says Swart.
Staff members like receptionist Pikoli Ngenge says of the new building: “It’s so nice to work here. I like the structure and the layout; it’s like all the pieces of the puzzle just fit.”