A compilation of facts underscoring the strength of marble, granite, and other types of natural stone
Building materials play a major role in global concern for climate targets. We compiled the most poignant arguments for use in meetings with customers.
LSI Stone of Portugal coined „susSTONEable“ some time ago.
In terms of energy consumption, CO2-footprinting, production, and, last but not least, disposal, natural stone has an outstanding track record.
* No primary energy at all is required in production. Marble, granite and other types of natural stone are there for the taking. Steel, on the contrary, requires melting the ore at temperatures of 1,400° C, glass requires 1,200° C and concrete requires cement, which, in turn, consumes a large amount of energy in production.
* Working the stone, e.g. sawing raw block into slabs, polishing, and cutting to size requires a similar amount of energy compared to other building materials.
* With respect to transportation, local material has the best track record.
* One important point in foot-printing is the longevity of natural stone. The material is resilient and thus durable. Surface renewal is easily achieved. Reclaiming material is more economical in terms of energy consumption than recycling: recycling e.g. of steel or glass requires melting down the material, a process which requires again very high temperatures and uses a lot of energy.
* And then there is the longevity of natural stone coupled with its strong emotional lifespan: one never tires of gazing at it.
* And natural stone is a good investment: marble, granite and other types of stone ensure permanent high value of real estate. One could say stone turns the home into a savings bank.
* At some point, of course, every building will be torn down. But when the time comes, stone can be reclaimed with minimal investment. This is true for flooring tiles, as it is for stairs and windowsills to name but a few.
* Even when downcycled natural stone can be reused again and again, finally finding its way to use as gravel or mulch – ashes to ashes, dust to dust, nature’s cycle for stone.
* Natural stone is also an excellent thermal reservoir. This is why kilns and burner-ovens are clad in stone. Some modern office complexes use stone floor tiles as part their climate control and air conditioning.
* Beside wood and clay natural stone is possibly the only building material that can claim to be 100% natural
* On balance there is a downside to natural stone: quarries have an indisputably negative impact on landscape. But defunct and abandoned quarries are quickly reclaimed by nature; even active quarries have their quiet corners in which rare flora and fauna can flourish in a protected surrounding. Clay, too, requires digging and neither sand nor gravel used for concrete fall from the sky. Only wood is a truly renewable raw material – but the commercial forest surfaces are never sufficient for building a city.
* Gardening and landscaping provide further opportunities for natural stone to expose its green side. Drywalling is all the buzz because it provides special living areas for fauna. Gabions are similarly eco-friendly, and stone heaps always provide living space for many small animals.
The Deutsche Naturwerkstein-Verband DNV has compiled exact figures in its study on sustainability. A digest can be downloaded free of charge in English or German.
Long version print: 10 € plus shipping
Above mentioned Portuguese company LSI Stone has done a lot in making sustainability a topic. One is a webpage, and one a video released long before Fridays for Future-campaign became known.
But even Kermit the frog knew that „It’s not that easy being green“ as he once sang in Sesame Street.
(05.06.2019, USA: 06.05.2019)