SUSTAINABLE BUILDING
The 2.5t solid rock bath – on the left of huge existing rocks.
The Khyber Rock House
Daniel van der Merwe and Gareth Griffiths
Leon Krige
What is a palimpsest design? Gauteng-based architect and management committee member of the Gauteng Institute for Architecture, Daniel van der Merwe, explains how his recent project in Sandton is based on palimpsest principles – respecting the site ' s legacy and the original buildings while building on them to create a greatly upgraded, functional home that retains its original vernacular.
Tucked into a rocky hillside in Johannesburg, the original House Millar – designed by Stan Field and winner of a 1974 SAIA Award – is a bold piece of Brutalist architecture. The renovation respects that legacy while building on the concrete theme. In keeping with this tradition, Daniel van der Merwe of Leaf Architects earned both a GIFA Award for Excellence and a Fulton Award for Excellence in Concrete( projects under R50m) for the transformation.
quiet, reflective pond that softens sound and shimmers with natural light. Near the main bedroom, an indigenous bio-filter lily pond merges seamlessly with a natural eco-pool and the outdoor living areas, integrating views and indoor-outdoor spaces with sensory experience.”
In keeping with the owner’ s and architect’ s vision, concrete remains the predominant theme for new additions.“ Indeed, in this project, concrete becomes sensorial; reflecting contextual design considerations and the craftsmanship of the contractors,” notes Van Der Merwe.
According to Van der Merwe, the new design leans into biophilic and site-driven thinking:“ Natural elements like rocks, trees, and topography became strong design generators. A mature tree now grows through the living space. There’ s an indoor forest atrium. Green roofs blur lines between landscape and architecture. The ethno-botanic landscaping draws spiritual and medicinal meaning, tapping into ancient knowledge and‘ place’.”
He continues,“ Water became important in the narrative. A waterfall over exposed rock defines the entrance threshold, backed by a
48 autumn 2026 | www. tobuild. co. za