Building with stone
As part of our RIBA research grant, we’ve been looking at both ancient and modern ways of building with stone. Here's a glimpse at what we've found so far:
We have known how to build with stone for thousands of years. Scarcity of materials once dictated our choice of construction materials and stone could be sourced from local quarries and then cut into transportable blocks. Structures were made of the ground beneath and around them.
As the industrial revolution took hold in Britain, coal and oil influenced how we built. We fired bricks and manufactured iron, steel and concrete as a cheaper alternative to the labour of making structures materially efficient. Stone became a luxury, reserved for decorative finishes, made expensive by the amount of stone rejected on aesthetic grounds.
All architecture
is extractive.
The energy required to make concrete, steel and bricks is in extraction, processing and transportation, whereas stone just needs to be extracted and transported. Quarrying is still a violent and loud process, but once a quarry is depleted it can be returned to nature, and huge amounts of stone are being made all the time as the Earth’s plates shift.
By using raw materials, buildings can be deconstructed at the end of their lives and their materials salvaged. The ancient practice of spolia takes antiquated stone gravestones, monuments and architectural fragments and reuses them. The practice had spiritual value, carrying memory down generations, but also represents a more frugal use of material.
With the industrial revolution, development in building with stone largely ceased. Due to large grants available for the study of new building technologies, engineering departments came to favour the use of these more carbon‑intensive methods. Yet extracting stone requires half the amount of carbon as concrete and can be 2.5 times stronger.
Building with stone largely means a return to traditional building techniques. But it doesn’t have to mean a compromise in structural strength and design ambition.
In Shanxi, China a95-metre bridge was made entirely of stone in 2001, crossing the Danhe river and supporting a four‑lane motorway.
Granite is tougher than steel, which is why it is often used for kitchen counter‑tops, but this robustness also makes it well suited for foundations. It is also the most abundant, making up 80% of the Earth’s surface. Traditionally, large blocks of stone were laid in trenches and lime mortar was used to bind them. We can now cut blocks of granite to be used as we would concrete block foundations. Large thin slabs of stone can be alsoused as load‑bearing walls, which also often negates the need for other external or internal finishes. Finding stone for domestic building in the UK requires looking in unusual places. The material is often available for garden walling and road kerbs but seldom listed as a readily available general construction material.