Location: windhoek, Namibia
Client: Paul Munting
This 240m2 home for an architect couple and their 2 children was designed on a 1300m2 triangular corner stand bounded on three sides by Uhland, Ossman and von Eckenbrecher Streets in Klein Windhoek.
The erf, undeveloped at the time of purchase, is characterised by its steep topography (it comprises of a small rock outcrop with a fall of over 12m along its length) and the indigenous vegetation that extends the character of the adjacent Aloe Walk trail into the surrounding suburb. The narrow southern-most portion of the site offered the most suitable location for building, given its somewhat sparser contouring. The small koppie on the property forms a picturesque backdrop for motorists travelling along busy Uhland Street in a north-westerly direction and it was this essential character, and its associated constraints, that guided and informed the design process.
While the placing of the main building on the site was influenced to a large part by the lack of buildable space on the erf it was also important that the above view of the site down Uhland Street be preserved as much as possible, together with the skyline of the rocky outcrop. For these and cost reasons an early decision was made to try and limit the extent of excavation and re-contouring to the absolute minimum. In order to maximise access to winter sunlight and reduce summer heat gain the main building was oriented as much toward north as possible, resulting in a NE orientation for the main façade. The rear façade onto Uhland Street is positioned on the erf boundary and was conceived as a service wall that would shield the living areas from the street while at the same time acting as a noise barrier. Steel cladding on the street side ensures ready access to the services accommodated therein.
The house is organised with sleeping areas on the ground level and living above in order to maximise the view to the south and northwest from those areas most frequently occupied. Two hardwood timber decks of Mesquite (Prisopis sp. – an invader species in Namibia) extend the living areas of the top floor to the outside. The detached garage and storeroom is located off Ossmann Street and defines the entrance to the property while providing a measure of privacy to the bedrooms behind it. A planted roof over this outbuilding ensures that unsightly roofing materials do not disturb the view from the living areas above.
The structure is a hybrid of load-bearing brickwork and steel portal framing that facilitates the more generous glazing of the upper floor living areas. Attractive, high quality, fired clay face bricks are virtually unobtainable in Namibia unless imported from SA or Botswana, and these invariably come at a hefty cost premium. For this and environmental reasons a local source was selected that manufactures from recycled mine dump material in Uis, producing a strong and attractive but porous clay brick. The porosity problems were overcome by the addition of lime to the mortar while white cement was used to modulate the colour and appearance thereof to compliment the masonry and the natural surroundings.
The steel, both structural and otherwise, was left unpainted throughout, primarily to ensure that the building blended into the natural context as far as possible, but also to reduce maintenance. This is an experimental solution based on observations and corrosion predictions for what is essentially a very clean and non-corrosive urban environment with a high air quality. Needless to say the progress of corrosion remains a matter of keen interest to the authors and time will tell whether, and to what extent, it may be necessary to implement protective measures in the future.
Internal climate control in summer was conceived to function as a combination of the careful control of direct sunlight penetration and the use of thermal mass with night-time ventilation for cooling. Steel shutters on the ground floor bedrooms permit secure but generous ventilation of the sleeping areas at night while louvers above the internal bedroom doors ensure that airflow is unimpeded along its path through the house to the top floor.
Passive heating in winter is achieved with a combination of direct solar gain and the use of massive materials to store heat at night. Given the constraints imposed by the orientation however, it was considered prudent to install a wood stove to provide the satisfaction of a hearth and extra warmth on the occasion that night-time temperatures really plummet.
Water heating is solar, with electric backup.
Essentially, this house expresses an effort on the part of its authors to find an architectural language for their home that would articulate their love for the Namibian landscape through its material use, respect for the existing flora and sensitive relation to the site. The project remains a work in progress, as one suspects is the case with most architects’ homes, and efforts to tweak the appearance, finishing and climatic performance continue to afford the owners a lot of pleasure.