Rosebank Towers

WSP in Africa achieved a 4-Star Green Star SA As Built rating, including a keen focus on Local Connectivity, for Rosebank Towers – setting another benchmark in sustainable buildings.

Rosebank Towers is located in the heart of Rosebank central business district, at 15 Bierman Road. As a brownfield project, the project has a total gross floor area of around 25 500 m², where the original buildings on the site were demolished to make space for the new development - 94% of all construction waste was diverted from landfill.

Additionally, the building is also in close proximity to an array of amenities, from schools to medical facilities, restaurants, spas, retail outlets, sport facilities and, great connections to transportation nodes – including the Gautrain - within allowable walking distance. This inspired the decision to target a local connectivity innovation point, by means of exceeding the Green Star SA Benchmarks, which has never been rewarded within the Green Star framework. The South African Green Star rating guidelines requires that a building has convenient, safe access to a minimum of four prescribed listed amenities - and in the motivation WSP submitted to the GBCSA on this project provided evidence that the Rosebank Towers in fact has access to all the prescribed listed amenities and more. 

The scenario case study provided evidence of the benefits for the environment through the reduction of automobile emissions - due to the close proximity of all the amenities, the number of automobile trips that would usually be required are significantly reduced. This also proved to be greatly beneficial for the buildings occupants, as less time spent travelling creates opportunity to significantly reduces the perceived stresses of time constraints and traffic annoyance.

The H-shaped multi-tenanted sixteen storey tower comprises a basement, seven parkades, and a total commercial office area of around 19 000 m² across seven floors that are very flexible and easy to sub-divide into approximately 600-800m² premises for smaller tenants in the future. The building also contains a 3 000m² fitness centre, with expansive views to the West and South. 

Due to the building’s orientation, design and building services specifications, it has been designed to achieve a high level of thermal comfort and a climate-controlled space for the building occupants. During the construction and commissioning phases, an independent commissioning agent was active to ensure all building services were commissioned to operate as per the design intents. 

The building also features several day-lit atria - and glazedfaçades  that allows 81% of the Office Usable Area access to views of the outdoors in addition to adequate daylighting. Furthermore, the landscaped terraces offer incredible views overlooking the Johannesburg and Rosebank CBDs. 

Abland, as the developer and co-owner of the building, have recognised a growing demand in the market for multi-tenanted ‘green spaces’ and embraced sustainable building requirements as a policy for Rosebank Towers - where the brief from Abland was to design a green base building that would meet the requirements for the 4-Star As Built rating.

During the construction phases, further support was also provided by WSP to Redefine Properties ensuring alignment of their interior fit-out to the sustainable features of the base building – the Redefine Fit Out achieved a 5 Star Green Star Interiors Rating. Other tenants were provided a tenant fit-guide, where recommendations are provided, as tenants look to manage and align their own interior fitouts with the base building green design.  

Additional sustainability interventions at Rosebank Towers include:

• 150% improvement on SANS 10400-0 (2008) requirements for fresh air rates for 100% of the office area.
• Water efficient sanitary fixtures were installed throughout the building. The demand for potable water consumption for landscape irrigation – on the terraces and grounds - has also been reduced by 70% through the installation of a drip irrigation system, with irrigation controller and mulching. 
• An automated building management system (BMS) has been installed which monitors systems and meters, as well as notifies the building owner of any alarms, or faults within the services.
• The building is equipped with an adequately sized waste recycling storage room.
• Ice storage technology has been used for the HVAC system, which results in a peak energy demand reduction of 36% – and no water consuming heat rejection systems have been provided within the building.
• Refrigerants and insulation utilised for the building system all have a Zero Ozone Depleting Potential.
• Low Volatile Organic Compounds (VOC) paints, carpets and sealants were used exclusively in the base building (shell and core space of the building).
• The building materials utilised to construct Rosebank Towers were locally sourced, where 20% of the materials were sourced from within 400km and 10% within 50km, reducing the transportation emissions due to the close proximity of material extraction to the site.