Greenstone Wildflife Estate
Located on one of the most difficult sites on the Greenstone Wildlife Estate in Barberton, Mpumalanga, this house was built in 2009 for the Estate's Developer and his wife, - a retired couple - with ample space for children and grandchildren to visit.
Built along a river, the flood-line necessitated that the ground floor be raised above the sloping ground on the river side, whereas on the entrance side it is only slightly higher than the ground level. This allowed for a number of raised decks with different conditions – covered, uncovered, semi-enclosed, others balcony-like, onto which the different rooms open and which allow for choice, depending on climatic exposure and function. All was made possible with cantilevered steel-frame construction, which also allowed for large uninterrupted spans between building tracts and lightening the appearance of the bulk of the house.
Predating the new energy-efficiency legislation, the client requested a glass box for the main volume, which was resolved with Smartglass's Colourvue Serene Green Low-E 7.38mm Laminated Safety Glass, within a structural steel frame and this permitted the extensive use of glass in the hot climate by means of the tinted glazing which cuts out solar heat gain and ensures that the space remains comfortable in the mild winters via the low-E coating. Sliding-stacking doors allow the house to extensively open up to the facing hill and river for natural ventilation and blur the boundaries between indoor and outdoor living.
The glass box was then “grounded” by a riven-stone clad tower in a light green stone finish, which recalls the name of the Estate, Greenstone - that refers to some of the oldest rock on earth found in the Barberton area and which predates the presence of oxygen on our planet. The tower marks the entrance and grounds the floating element of the glass box and the cantilevered decks to the terrain. A double-volume living space allows for dramatic views of the hillside opposite the river but an equally important heart of the house is a cosy, deep sheltered veranda for outdoor living, adjacent to the double-volume glazed internal space. This was not explicitly required by the owner but is greatly appreciated, and is my favourite space, since it is the "in-between" area that unites the living wing and the main bedroom wing and is the main entertainment area. It’s enticing darkness invites one to inhabit it and offsets the lighter, brighter elements.
Flexibility in approach during the construction process contributed to changes in the design - following topographical difficulties the decision to abandon a solid base for a "floating" one was made by the contractor. The originally-planned gabion walls making up the base were never built, instead the cantilevered steel shelf was left exposed. Smaller changes by the Client and Contractor via phone calls to the architect in Johannesburg and on rare site visits all led to the improvement of the final design.
"Living here is simply fantastic, we feel at home in nature," say the owners.