78 Corlett Drive achieves six green star rating – greenest in South Africa

Roger Brookes, Projects Director, architect Enrico Daffonchio and Michele Brookes, Managing Director of Legaro.
Roger Brookes, Projects Director, architect Enrico Daffonchio and Michele Brookes, Managing Director of Legaro.

Boutique developer of exclusive lifestyle and commercial properties, Legaro has been awarded 2018’s highest rated green building in South Africa at the Green Building Council of South Africa’s 11th Green Building Convention gala dinner. 

Solid Green Consulting were the consultants responsible for the rating which achieved the award.

Legaro’s Managing Director, Michele Brookes comments:

“This is a tremendous honour for us. We are passionate about the environment and limiting society’s impact on our natural resources.

For the Legaro brand, this is something we live on a daily basis, and developing a head-office with a zero carbon footprint was a natural progression for us.

To be recognised as the highest rated green building in the country is a great kudos to the collaborative effort and vision between ourselves, the architects, surveyors, suppliers and other parties.”

The criteria for the qualifying green projects are based on submission data gathered during the GBCSA’s Green Star certification process and the strength of the submissions. Individuals are nominated by the industry ad their Green Star engagement is also taken into consideration.

“78 Corlett Drive in Melrose North, Johannesburg was a brown fields conversion, which provided its own set of unique challenges” comments Roger Brookes, Projects Director.

“Before we could start with demolition of the old building, all harmful material had to be correctly removed and certified.

Our biggest challenge was soil preservation: it can take up to 500 years to produce 2.5cm of topsoil. All the topsoil removed was relocated and used in gardens. We managed to recycle approximately 90% of the waste from the demolition.

Process administration was probably the most onerous task – all waste had to be quantified and appropriately recycled, down to the plastic wrapping around the bricks and the cement bags.

Internal finishes such as paints, adhesives and carpets had to comply with strict regulations around volatile compounds.”

Legaro was the developer and main contractor for the construction and is also the anchor tenant of the multi-storey building that comprises a gross lettable area of 1 586m2 on a 2 000mland parcel.

Daffonchio Architects were responsible for the conceptualisation and design of 78 Corlett Drive.

“Legaro approached us with the concept of developing an off the grid, green building. From day one minimising their environmental footprint was a core value for them,” says architect Enrico Daffonchio.

“Planning was absolutely paramount. Collaboration and attention to detail between the client, ourselves and the contractors was key to the success of the rating,” he continues.

Daffonchio and his team applied intuitive software to do light and heat studies, ensuring that the building is functional as well as carbon neutral.

“Our biggest challenge was to design a functional façade that was both cost effective and looked aesthetically appealing. Especially the north-facing façade required extensive protection from direct sunlight and heat, without compromising on natural light.

In collaboration with the contractor, we designed a shutter system that aligned the window sizes and the aluminium composite sheets for the louvres. The efficiency ended up in the high 90%, with almost no cut-offs or waste.”

Daffonchio also ensured that the staircase remained a focal piece in the overall interior design, encouraging tenants and visitors to walk up to the second story instead of making use of the lift.

Services and circulation were located in the core, minimising service costs, such as long pipes requiring more insulation.

“We placed the offices at the outer edge of the building, maximising the use of natural light and ventilation. Some 86% of our offices have natural light and ventilation,” explained Brookes.

Apart from a carbon neutral design, 78 Corlett Drive also boasts recharging facilities for electric vehicles as well as full cyclists’ facilities including undercover parking, showers and change rooms. All lights are energy efficient, only reaching a predetermined maximum energy level. Due to space restrictions grey water harvesting were not included, although the building is water efficient.

Development costs were approximately 8% higher than conventional construction methods, mainly as a result of the solar panels and shuttering installations. The shutters play a critical role in maintaining the building’s ambient temperature throughout the seasons.

Legaro expects that the energy savings from the solar panels will be offset by a saving in rates over time.

“There is a lot of development happening in the node, and it’s encouraging to see how renewable energy is being used. We think it’s only a matter of time before it becomes main stream.”

This may happen sooner than most developers and tenants realise, with building regulations expected to become increasingly focused on energy and resource efficiencies with limited to zero impact on the environment.

Currently all  new buildings have to use solar water heaters, heat pumps or similar technologies, while ceilings, walls and windows have to meet minimum requirements in insulation to minimise temperature fluctuations. Buildings will also have to be fitted with energy-efficient heating, air conditioning and mechanical ventilation systems. The Green Council’s aim is to have a net zero impact by 2030 and all existing buildings to be compliant by 2050.

Legaro used the Green Council’s EDGE (Excellence in Design for Greater Efficiencies) software to measure the resource intensity of its 78 Corlett Drive development. The EDGE standard is set at a minimum of 20% reduction across energy consumption, water usage and embodied energy.

The company intends implementing the same principles in its upmarket residential and commercial developments.