The eco-poetics of the Heritage Portland Stone Brick

Sustainable housing development does not necessarily need to mean an undulating sedum roof or a living wall which blends artificially into the natural landscape.

It can also mean thinking critically about the materials and processes which inform the construction process, drawing inspiration from the pre-industrial past and subsequent phases of industrialisation to develop considered responses to the Climate Emergency. The focus for architects must be on sustainability at both the local and the macroscopic levels, and it should involve working with suppliers who have strategies for mitigating and ultimately reversing their carbon impacts.

An alternative to the traditional fired clay brick emerged in Dorset recently, as Steve Moore and Alexandra Green built a house using natural bricks cut from Heritage Portland Stone. This unloved and unusually fossil-rich material, typically considered too irregular for building façades, has often been overlooked by the architectural profession. Sensibilities have traditionally focused on the smoother, more pollution-resistant dress stone, applied most famously in the great civic buildings of the Baroque, Neo-Classical, and Neo-Baroque movements. It is thought that by putting it to use as a ‘brick’ it will not only reinforce arguments for expanding the use of natural materials but help meet demand for a product which, while more sustainable than most, nevertheless relies on the combustion of fossil fuels.

The brickwork for the first Portland stone house commenced last Christmas, and despite some scepticism at first, the builders were ultimately pleased with the visual effect of stone. When crafted into a wall, the stone’s natural variations came through to create a collage of details, described as ‘tapestry-like’ by Moore. The stone implies a meaningful relationship between the building and the ground on which it sits; it suggests durability and longevity; and it demonstrates the potential for collapsing the conventional binaries between material categories and applications.

Isle of Portland heritage brand Albion Stone is one of a growing number of suppliers to invest in the technologies required to produce brick alternatives. Sister company Hutton Stone on the Scottish Borders is developing its capabilities in stone brick production, whilst other companies in Somerset, Oxfordshire, and Gloucestershire are experimenting with rammed earth unfired brickmaking techniques. These materials require minimal processing, reducing the energy needed for production and the embodied energy associated with the building after construction. Portland stone brick in particular promises a 75% lower carbon footprint when compared to traditional clay fired bricks, and this does not account for the notion that this supports a greener, domestic stone industry.

RDA architect Frederico Marques argues that incorporating these bricks into the long-term ambitions of the practice could promote sustainability as well as beauty. He sees them as ‘evidence that the transition towards greener materials and technologies has the potential to enhance the look, feel, and atmosphere of buildings’. There is now more justification than ever for working with specialist craftspeople to fashion buildings with green objectives.