Westend Building C, part of the modern Westend office development in Centurion, received its 4-Star Green Star SA Design certification from the GBCSA just weeks before South Africa went into lock down.
With a useable area of 6,214sqm, Building C is the third of six buildings to be developed by Abland Property Developers in the Westend Office Park, with MWLF as project architects and Solid Green Consulting as sustainability consultants. Grant Silverman, marketing director at Abland, says, “Abland Property Developers strongly believes that, in today’s times, it is essential that all its developments are designed in the most efficient way possible, to be both good for the environment and reduce the occupation costs for the tenants that occupy these buildings upon completion.”
Shared Concept, Individual Identity
Jeremy Williams, director at MWLF Architects, explains that the design themes started in the development’s first building are evolving as subsequent buildings are developed: “The concept is a family of buildings that share a DNA, but with each building having a unique identity that responds to the movement of time and trends as the park evolves,” he says. “The buildings are designed economically to have efficient floor plates and to be able to accommodate a variety of tenants, with individual facade articulation creating design interest and highlighting the positive and negative forms of each structure.”
The six-storey Building C has a rectilinear floor plate with a central core that allows lobby access to 4 flexible subdivisions of 325 sqm per floor. Williams adds that the ground floor of the building contains a recessed parking level, forming a base upon which the projecting office floors and ‘floating cubes’ of white structure rest. “These floating elements are eroded and cut into with windows and balconies to articulate the form through a play of solid and void“.
“A concrete end wall acts as a holding element, framing the negative space and cube, and folding over to form a top to the building. This entire facade is then reversed and mirrored on the alternating facade, creating two asymmetric end fades. We also introduced a strong diagonal element in this building, which will be carried forward in Building D.”
User Wellbeing & Productivity
For years, it has been widely acknowledged that the design and management of buildings are critical to enhancing users’ health and well being – both in terms of productivity, and mitigating disease and absenteeism. “In commercial building typologies, salaries are the biggest cost to companies, so an improvement in staff health and productivity will bring a direct return,” says Marloes Reinink, director at Solid Green Consulting.
“And, in times of almost unprecedented economic uncertainty, this is an area that should receive increased attention from business decision makers.”
Makhosazana Mthethwa, sustainable building consultant at Solid Green, explains that Westend Building C incorporates several green building principles that are geared towards user well being, such as a balanced window-to-wall ratio that allows ample natural light into the offices. Furthermore, 89% of the office floor plates have access to external views.
“The building also uses non-harmful materials in the interior spaces,” says Mthethwa. “For the interior fit-out, and for any future refits and expansions, paints, carpets, adhesives, sealants and composite wood products will be specifically selected to minimise emissions typical of materials containing Volatile Organic Compounds.”
The integration of physical activity is essential to achieving health and well being, and Building C makes provision for a more active, less sedentary, lifestyle through walkability and accommodating non-motorised transport options. Sited just over 1km from Centurion Mall and within 700m walking distance of the Centurion Gautrain Station, the building provides cyclist facilities on the upper basement level with two changing rooms and showers next to the main entrance lobby and secure bicycle storage for both staff and visitors on the same level.
Preferred parking bays for fuel efficient vehicles like hybrid or electrical cars as well as mopeds, scooters and motorcycles have been provided on the lower, middle and upper basement levels close to the lift core and lobbies. Car-share vehicles can also make use of these bays if there is a contractual agreement between the tenant and car-share company.
Behaviour of occupants is critical to reducing overall consumption, and energy and water sub-meters have been provided for all substantive energy and water uses to facilitate ongoing management of resource consumption.
The building recorded a simulated 53% reduction in energy consumption when compared to a building constructed to SA National Standards. The lighting power density for artificial light is limited to 1.5W/sqm per 100 lux to ensure minimal energy consumption. This is achieved through the use of LED lighting for at least 95% of the offices. All spaces are individually switched, and occupancy sensors linked to the lighting system enable lighting of occupied areas only.
Hot water is provided through the use of a 5,5kW heat pump to showers in the upper basement level and for use in kitchens and wash hand basins. Water saving initiatives include water efficient sanitary fittings, and an air-cooled heat rejection HVAC system rather than a system using potable heat rejection water. The system uses refrigerants with an ozone depletion potential (ODP) of zero; and does not include any component systems that might pose a risk of legionella infection.
A 21sqm recycling and waste storage area is conveniently located for precinct service collection at the Upper Parking Level, with easy access to dedicated sorting bins. This area is linked to Westend Precinct larger waste and recycling centre which facilitates sorting of paper and cardboard; plastic, glass and cans; metals; and general waste.
The project team estimated the Green Building cost premium to be as little as 1%. This is due to an already high quality Abland baseline building standard that incorporates green design principles. Reduced potable water and energy consumption are also anticipated to significantly lower the building’s operational utility bills.
The project targeted a Green Star Innovation point for Financial Transparency. According to the GBCSA Technical Manual, the aim of this credit is to “encourage and recognise the sharing of costs/financial information related to the design, construction and operation of green buildings in the context of the Green Star SA certification process, that will create greater market transparency and awareness of the cost trends related to green buildings.” The data is also used as input in a research project by the University of Pretoria to provide insights into the cost of going green on buildings in South Africa.
Post COVID-19 Building Strategies
“Climate risks have become part of the mainstream building conversation over the last decade, further highlighted by serious energy and water supply issues,” says Reinink. “In planning for a post-COVID-19 building strategy, health-related risks will join the Resilience conversation – requiring changes to design and construction methodologies for all building typologies.”
As the links between urbanisation, climate change and public health become more apparent, current building practices are expected to fall under scrutiny, and projects like Westend Building C will point the way forward.