The stones of the British Isles have contributed more than any other building material towards defining our built heritage, from the grandiose to the vernacular. And they still do. But while everyone wants the stone, there is less enthusiasm for the quarries
From the Portland limestone of St Pauls to the humblest barn or dry stone field boundary built from whatever stone happened to show through the soil, the stones of the British Isles have been used for centuries, even millennia, to create the urban and rural landscapes so admired by those who live in them and visit them.
But if the buildings are admired, the same cannot be said of the holes from which the stones come.
The latest survey by Saint Consulting, an American lobby group specialising in property development who moved into the UK in 2005, says a quarry is now top of the NIMBY list. In 2008 quarries came behind casinos, powerplants and landfill sites. Not any more. Now what people most don’t want in their back yards is quarries. And they make no distinction between the relatively small scale operation of most dimensional stone quarries and the large scale production of aggregates.
Planners should pay more attention than the public in general to the difference in the size of the operation because guidance from the Depart-ment of Communities & Local Government (CLG) to planning authorities in Minerals Policy Statement 1 (MPS1) requires them to do so.
That they should was one of the outcomes of the Symonds study of the stone supply industry in 2003, as a result of which came the report Planning for the Supply of Natural Building & Roofing Stone in England & Wales.
The report also said sources (and potential sources) of stone should be identified to help ensure planners do not sterilise them by allowing other developments on them, such as housing or factories. Many former quarries have been built on, depriving significant historic buildings of the original source of stone for subsequent repair, maintenance or extension, as well as depriving today’s construction industry of a source of that material.
To supply planners with information about their local geology requires the identification of stones used historically and sources of that stone, or suitable alternatives to it. That study, called the Strategic Stone Study that was publicly announced in 2006, is currently underway jointly by English Heritage and the British Geological Survey (see page 28 for the latest up-date on that).
Iain Kennedy, the chairman of Stone Federation’s Quarry Forum, despairs of the planning process. He is the Managing Director of Realstone, one of the UK’s largest stone groups that includes Block Stone, who extract the stone from 10 quarries. He told NSS: “The hoops you have to jump through! In a lot of cases it just isn’t worth the cost. And even if you jump through all the hoops and satisfy the planning officer, it’s still reliant on a committee agreeing to it. It’s very difficult, especially for a smaller company – which is the majority of the stone industry – and there’s little or no help from the government in this respect.”
He says that in spite of MPS1, local authorities often do not make a distinction between aggregate and dimensional stone quarries.
The deputy chairman of the Quarries Forum, Michael Poultney, who is Managing Director of Portland limestone quarry company Albion Stone, says that while British stone companies are counting butterflies to satisfy the planners, their overseas competitors are counting the profits.
Albion Stone and Stone Firms, the two companies that supply Portland limestone, are suffering from a major fall in construction activity in the City of London as the bankers count the cost of their credit crunch. Both firms are reducing the size of their workforces.
Many producers are not as badly hit. Some are even taking on more people. Black Mountain, for example, who work their own quarries and import stone, have found an increased demand for indigenous stone, although demand for the less expensive imports has fallen. They have had to increase the workforce in their quarries to meet demand for their stone.
Black Mountain MD Adrian Phillips told NSS: “It’s the more discerning people who still have the spending money.”
David Marchington from Marchington Stone, who quarry the Shire Hill gritstone from Derbyshire that was used at the front of the Victoria & Albert Museum in London, are also planning to expand their business, although a planned investment on new saws is in the balance.
“It’s not on a back burner,” says David, “but it’s not on a front burner, either. Perhaps now is not the right time. Business is OK. It’s not great anywhere but it’s not all doom and gloom, either. We’ve got loads going on.”
Imports of stone now undoubtedly account for the largest part of the stone industry in the UK. Simply looking at the stones used on projects makes that indisputable, even though official figures, especially for UK stone production, are sketchy and suspect.
Some small companies do no more than report the limited figures they are required to supply to Companies House and some aggregate companies that report selling dimensional stone have denied selling block, scants or even walling or rockery stone when questioned by this magazine.
Often the decision to use foreign stone for a project is due in no small measure to the price advantage over British stone, sometimes resulting from economies of scale, often made possible by the geology, and sometimes from labour costs and government policies.
Nevertheless, the massive increase in imports of stone since 1996, when the industry started to recover from the last recession, has created a new aesthetic for natural stone that has pulled sales of the indigenous materials along with it.
Facing competition from cheaper imports must have had a downward pressure on the price of indigenous stone, although the higher volumes sold have accommodated that pressure through gains in productivity achieved by investment in new machinery – it has been a busy time for all the machinery suppliers, although they saw orders slump after September last year.
On the other hand, strong demand limited the downward pressure on prices of indigenous stone and even now demand has dropped, the crash of sterling is cushioning UK suppliers by increasing the prices of imports. In fact, with sterling having fallen so far, British stone is starting to look like a bargain. It has certainly helped Block Stone, one of the few British stone extractors who regularly export, to increase their sales overseas.
Not all producers will see it this way, but imports have, in general, had a beneficial effect on the indigenous stone supply industry in the British Isles.
One problem they have raised is the question of sustainability. And concrete paving product manufacturers in particular have been quick to exploit that.
Cheap granite and sandstone from China and India have changed the face of urban Britain. They have made natural stone hard landscaping available at little more than the cost of concrete products. Local authorities and developers have enthusiastically swapped over to the natural product because they perceive it as raising the status of the area being developed, especially derelict industrial quarters that are being turned into desirable residential districts and town centres.
But stone that has travelled thousands of miles from India, China or Brazil does not have the minuscule carbon footprint of stone dug out of the ground in the British Isles. Concrete product manufacturers have been quick to note that fact and compare the carbon footprint and sustainability credentials of their products favourably with what is perceived to be environmentally friendly stone.
Employment practices in developing countries can also leave something to be desired and, again, concrete products companies have used this to attack natural stone products. At the same time they have tried to make their products look more like stone and have developed features such as porosity to allow water to soak away on hard surfaces.
Their aim is gradually to raise doubts in planners and developers minds about just how green stone is. And so far the stone industry in the UK has done little to fight back.
Iain Kennedy: “Without doubt the stone industry has been very slow to get on to the eco band wagon. Part of the reason for that is because it’s so blatantly obvious that stone is eco-friendly why bother to tell anyone? But, of course, it isn’t blatantly obvious to everyone outside the industry.”
He told NSS that Stone Federation Great Britain had engaged a consultant to produce a report on the environmental impact of stone that will produce some headline figures this autumn or winter.
“We were all hoping that was what the Green Guide from the BRE would do and during the two years that it was being produced we hung our hats on that,” says Ian.
The Green Guide takes methods of building and gives them a rating. For example, ‘Sandstone rainscreen cladding and steel support, insulation, lightweight solid blockwork wall, plasterboard, paint’ gets a ‘B’ rating, when ‘A+’ represents the most environmentally friendly.
There is a feeling in the stone industry that the bigger and wealthier brick and concrete product manufacturers were more successful at lobbying the BRE than was the stone industry and that consequently the criteria used for measuring sustainability benefited those industries.
BRE has said that stone loses out in terms of waste and water usage, but much of the so-called waste (finished masonry can easily use less than 50% of the stone in a block from the quarry) stays in the quarry as backfill or to become other products such as walling or rockery stone. Even dust is sometimes used in mortars. And while processing stone does use a lot of water, it is often not potable water from the mains but collected rainwater, because treated water is expensive. Whatever the source of water, there are not many companies who do not recycle it to minimise consumption.
British stone producers say they supplied the figures required by BRE for the Green Guide that were given various weightings to produce the results that have been published.
“The thing that annoys me most,” says Iain, “is that we couldn’t get to the bottom of the methodology. There are a lot of positives for stone in the Green Guide, but we feel there should be a lot more.”
The Green Guide illustrates what happens when attempts are made to simplify information for comparison purposes and perhaps explains why most studies are infuriatingly short of simple, straightforward answers.
This magazine’s own attempts to get some simple figures relating to electricity and diesel used to extract a tonne of stone hit its own barriers. Some companies were willing to submit figures but there was such a huge variation in a tiny sample that aggregation was meaningless.
Some figures from the University of Bath (www.bath.ac.uk/mech-eng/sert/embodied) put general figures on aggregated categories and come to the conclusion that cement in general typically results in 1,482% the CO2 emissions of the production of ‘stone’, although the figures for stone include gravel and chippings and carry a comment about a large data range on slate. Concrete in general had 232% the CO2 emissions of stone in its production, lower than cement because of the large volumes of stone that can be crushed to produce the aggregate in concrete for relatively little energy.
No doubt arguments about the sustainability of products will continue as long as customers want to satisfy themselves that the products they are using are ecologically sound.
In the meantime there may be good news for some British stone from the new British Standard 8298 when it is published later this year. It puts more responsibility on designers (which could include stone companies who are involved in the detailed design of the stone element of a project) to establish the suitability of any particular stone for a job.
This should benefit stones such as Portland limestone. Suppliers have long argued that they are put at a disadvantage because the Standard has meant Portland has been specified in thicker sizes than imported limestone, making it more expensive.
Peter Harrison of Croydon consultants Harrison Goldman says designers will be able to use test results from suppiers, which will not be a problem for established stones in the UK that already have the information available but could add £5,000 worth of tests to some unfamiliar stones from other parts of the world.
Peter says other changes to look out for are the Building Regulations in March 2010, when part ‘L’ will tighten the ‘U’ value requirements again to make walls even better at keeping the heat in. And in 2011 the Construction Products Directive, which most of Europe took to mean they had to CE mark products including stone but the UK opted out of, should become the Construction Products Regulations that the UK cannot opt out of. However, a week, let alone two years, is a long time in politics, so the timetable may change.
In the next issue of Natural Stone Specialist we will be looking at how stone companies are developing new ways of using stone as a modern cladding material with off-site manufacture to meet the fast-track requirements of today’s developers.