A NEW CORNISH STONE HOUSE

[Article for The Journal of the Worshipful Company of Masons, 2019-2020 Issue]

Newham, a new country house in Cornwall, may look traditional but it addresses two urgent contemporary issues:

1) The erosion of cultural distinctiveness (perhaps a symptom of globalisation) whereby the built environment takes on the bland, could-be-anywhere attributes of an airport transit lounge.

2) Climate change. Well, everyone knows about that but as far as buildings are concerned there is often a concentration on energy in use, with little regard given to the embodied energy used for construction and then the expected life of that construction.

Clearly a building designed to last 30 years is less “green” than one that will last more than 300 years.

England is a land rich in visual variety. We know when we are in the Cotswolds, when we are in East Anglia, and so on. Much of this richness and diversity is the product of our native building stones (or, as in East Anglia, the comparative lack of any). Distinctiveness is an invaluable inheritance identified as “The Pattern of English Building” by Alec Clifton-Taylor in his great book of that title. But the “Pattern”, the richness and diversity, is being eroded by a modern desire to be different, to eschew local traditions and local materials. And this is the paradox: in seeking to be radically different modern architects are not adding richness, they are tending to sameness. A building that could equally be at home in Bracknell, Bishops Auckland, Bolton, or Bodmin is an impoverishment – because so many others are producing the same sort of thing.

Stone, because it contributes so much to the local character is central to combatting this decline. Newham uses local materials, building in a distinctively Cornish way:

  • Granite for columns, lintels, gate piers, steps, etc from the De Lank quarry 15miles away.
  • Roofing Slate in diminishing courses from the Trevilett quarry 25 miles away.
  • Rubblestone walling from (called “killas”) the slate seams to the north and east, some 30 miles away.
  • Slate Paving from Delabole, 22 miles away.

Newham is not an intruder in its environment, it really is a part of it!

This is a sustainable way of building. Extracting the local stones, converting them to the required shape, and then incorporating them into the fabric of the building requires comparatively little energy. And they last for a long time: roofing slate should last for a hundred years before it needs major work, stone-walling for several hundred years and large sections of granite should be good for several thousand years.

Despite its traditional appearance it would be a mistake to suppose that Newham is some exercise in historicism, modern technologies were used whenever they gave a benefit. The walls are cavity walls with a 200mm stone facing – a durable strong wall with excellent thermal insulation and weather resistance some 550mm thick. This is to be compared to a traditional rubble wall, 600-750mm thick, with poor thermal and weather resisting qualities.

Cornwall has always favoured monoliths and large sections of granite because less energy (from men or beasts) was used transporting huge and heavy stones than there was in making them smaller. This tradition has been maintained with some individual stones weighing over 3 tonnes. These weights are easily handled by hydraulic equipment. It is liberating: one can now build with large stones at no extra cost. Thus the entrance columns are monoliths and the lintel they carry is a monolith. The columns stand on the threshold porch stone – the stylobate in neo-Classical terms – a stone 3500mm long, 900mm wide and 400mm thick. In other words the steps and paving are part of the primary structure – a form of construction used by the ancient Greeks and before them the Egyptians and others for some 4,000 years – large, heavy stones needing to be precisely located. But because of mechanical handling, it was built by local ordinary general builders, not specialists.

For the interiors there was no suitable Cornish stone readily available and so Portland stone varieties with lots of shell and fossil were selected:

  • Grove Whitbed for the columns, also monoliths, set in their natural bed and displaying an intriguing history of marine sedimentation from top to bottom.
  • Jordan’s Whitbed and Fancy beach Whitbed for the chimneypieces.
  • Jordan’s Basebed a fine gained stone, for the cantilevered staircase.
  • Jordan’s Whitbed in random sizes for the flooring.

The main entrance hall welcomes visitors with a large Portland stone chimneypiece and a stone cantilevered staircase. Stone cantilevered stairs have been built in this country since 1635 (the first being the Tulip Staircase in the Queen’s House at Greenwich). They are a common feature in Georgian and later buildings, an inherently elegant form of construction. But their use died away in the 20th century, partly perhaps because of that century’s love of concrete, but also because they couldn’t be structurally justified. That is no longer the case mainly due to the work of Sam Price and his colleagues.

Now, happily, the construction of stone cantilevered stairs is a flourishing trade. And a good thing too!

Stone stairs are far more beautiful than any concrete stairs, they contain far less embodied energy, they are far more environmentally friendly.