This hard landscaping project was short-listed in the small-scale development category of the Landscape Institute Awards last year. It was Highly Commended. Some think it should have won.

Macauley Walk is in the Clapham Conservation area of south London. It is in an area of only 0.7hectares that once contained the factory of optical firm Ross & Co. The 19^th century buildings of the company have been sensitively re-used alongside new builds in the redevelopment of the site, with the buildings, old and new, framing a pedestrian right of way from Macauley Road to Clapham Common.

The landscaping of the development has been designed by Churchman Landscape Architects using predominantly Italian and some Chinese porphyry supplied by stone hard landscaping specialist CED, which has five depots providing coverage across the UK, including Northern Ireland.

The success of the scheme comes from its resolution of fine detailing and the careful selection and application of materials rather than cutting edge innovation.

The new pedestrian right of way carefully negotiates around the footprints of the old and new buildings. It is clearly delineated in the context of the residential environment, using water features in the form of a rill to distance the private residences from the public realm.

The rills read as a simple and understated element ribboning through the landscape, reflecting light and providing an audible (especially at night) gently babbling flow.

In fact, the rill is not a continuous feature but breaks down into five discrete sections. The channels are lined with Italian porphyry of varying widths, extending the paving pattern through and submerged into the rill.

The scheme was originally conceived in 2007 to provide another 98 dwellings in Clapham Old Town. It was put on hold in the recession of 2008 and by the time it was revived the landscape proposal had been invigorated by the heightened ambitions of the client. It was reviewed and redesigned to the enhanced standard that the finished work has realised, thanks to careful attention to detail by specialist contractor Lee Marley Brickwork, which, in spite of its name, is a respected stone contractor as well as a brickwork company.

Although the project was fairly small, it was intricate and awkward. As Michael Heap, a Director of CED, says: “It’s not always the case that jobs like that go well but at Macauley Walk the relationship between Churchman, ourselves and the contractor went extremely smoothly.”

Michael Heap is a stickler for detail and one of the harshest critics of poor urban landscape design. He says Macauley Walk contained some requirements that can often lead to a contractor compromising because it does not have the skills to do the job as specified. Michael: “It was the sort of detail that has a contractor saying ‘I don’t understand this; I can’t do it’, but Lee Marley didn’t. They did a properly good job.”

To say the stone used is porphyry is to describe it rather than identify it. Porphyry is igneous rock that has cooled near the surface, giving it a ground mass of fine crystalline grains around larger crystals. The Italian stone used at Macauley Road is porphyritic ignimbrite, which is believed to have been formed by pyroclastic flows from a volcano. When the flow comes to a halt it is extremely hot and the particles weld together. The resulting stone is strong, fairly lively in colour, has an attractive sparkle from the crystals and is impressively slip resistant with a natural finish.

The Chinese porphyry in the project has been used for the profiled edges of planters, for example.

There are some 350m2 of porphyry paving flags, 200mm to 400mm wide, and 250m2 of 10mm setts, along with about 50m2 of smolleri, which is where the stone is set on edge. It has been used as a way of identifying the edges of the rill and around trees, especially as a tactile warning for those with impaired vision.

The rills are lined with porphyry and a wall of the stone has been partially polished so that the tops of the peaks and troughs of the natural stone finish have been reduced by about 50%, creating jewel like facets in the wall without making the whole wall shiney.

Simon Rice, the architect on the project from Churchman Landscape Architects (CLA), says: “Michael Heap gave us a sample of this semi-polished porphyry and we thought it was amazing. We had to incorporate it.”

Working closely with the project architect, (Assael) and client (Grainger PLC), CLA developed this scheme to unify the diverse array of building scales and characters.

Simon Rice says: “Our role was to balance residential amenity and privacy with the function of the street – an unambiguous and accessible public thoroughfare within a robust and fine residential landscape.

“Our initial design explorations focussed on key issues of residential amenity and privacy and how these can coexist harmoniously with a prominent public right of way without resorting to overtly defined boundaries – a meditation on defensible space.” He says the material palette was crucial in providing an elegant and responsive solution.

Following the project’s two-year period of hibernation and the client’s return to it with renewed enthusiasm, CLA suggested an enhancement of the courtyard street as the central heart of it.

The new design concept was evolved, inspired by the previous light industrial use of the site while at the same time considering the landscape as an enclosed, framed extension of the dwellings.

Simon Rice describes the landscaping as “a composition with a language of surfaces, or fabrics, punctuated by singular jewel-like and beautiful objects”.

As well as the hard landscaping, mature trees help demarcate the public right of way as well as being eyecatching from adjoining streets, while conventional climbing plants and solid blocks of clipped hedge create walls of greenery.

Lighting has been hidden in the vertical edges of buildings with GOBOs controlling the shape of emitted beams. Catenary lighting strung from the buildings ensures adequate LUX levels are achieved without cluttering the restricted area with obstacles.

There was always going to be a potential conflict between the public and private areas and the challenge was to create a space that residents can feel comfortable with but that also provides a distinguishable yet engaging route for the public to pass through.

CLA did not want a clutter of different materials to define areas, but rather one material used in a variety of ways. Natural stone with its diversity of possible finishes and sizes and versatility of use was an ideal response.

The lively variety of colours in the porphyry, from burgundy and mauves through to greys and orange, combine comfortably in relation to the range of muted yellow, red and dark blue brick tones on the buildings.

The main street is laid with larger slabs in variable widths to represent the larger spaces and the common areas accessible as a communal and public thoroughfare. Smaller gauge long setts, or binderi, are laid into the narrower alleys that lead off the street, the change subtly expressing these more private areas. The smolleri help people negotiate safely past trees and water features while the semi-polished porphyry walls mark the entrance sequence from Macaulay Road.

The darker Chinese porphyry used for walls such as those adjoining entrance ramps to the old workshop houses and the large hedge planters with their incorporated linear light features provide a subtle colour contrast to the landscaping.

Sustainability and efficiency was also a consideration. Buildings have achieved a BREEAM rating of Very Good. In the hard landscaping, lifecycle costs were taken into account and materials were consider for their longevity, robustness and the ease with which individual elements can be replaced if they do fail.