19 Rockridge

19 Rockridge is a private house on a ridge in Johannesburg, looking north over the treed suburbs. The architecture is thin, low-pitched roof planes carried on steel and timber over glass, brick and stone, with deep overhangs. There is no loft and no ceiling void: the roof plane is the ceiling plane, inside and out.

Technopol supplied the roof and part of the external skin. The roof is LiteSpan 990 Standing Seam — Chromadek steel skins factory-bonded to a fire-retardant FRCel EPS core, 990 mm cover, white underside. It is fixed with a concealed 1.2 mm galvanised clip at every support, two screws per clip, so nothing penetrates the weather face; the only lines in the field of the roof are the seams. The upper walls are clad in LiteClad ClipClad, the 270 mm concealed-fix profile in 0.5 mm pre-painted steel, run vertically.

The demanding part of this job is that the panel is seen from both sides. Photograph 38 is a crew seaming the panel on the outside; photograph 46 is the same panel overhead as the finished ceiling of the double-volume living room. There is no ceiling board under it and no insulation blanket over it — the panel joints are the ceiling joints, and the factory skin is the finish. That is what a composite panel has to earn: a soffit good enough to live under.

It also had to be thin and shallow. The roof reads as a floating plane with a deep eaves overhang and no fascia bulk (photograph 17); the Standing Seam profile goes down to 3° pitch, and because the clip is concealed there is no fastener line to detail around at the eaves.

The cladding was fixed the same way: concealed wafer screws, no fastener heads on the face, landing on rails that are still visible in photograph 40 where the run stops. It meets raw brick and stone piers directly, without a cover trim.