Stonework is a beautiful addition to any building or landscape project. Stone is a natural material and incredibly durable, both great advantages when considering sustainable building practices. Even so, there are several factors to consider when planning to use stone in your project.
What type of stone will be used? Where is it from and how is it gathered? A significant percentage of the stone used in the mountains of North Carolina comes from central Tennessee. This sandstone is lovely and very easy to work with, but it is costly in energy and money to bring it here. The customer and the planet both pay. Finding local stone supplies reduces the impact of freight and gives the project a look of belonging to this locale.
Unfortunately, there is not much green about the way stone is gathered. Large scale fieldstone gathering often resembles clear-cut logging, with large excavators scraping the hillsides for stone. Quarries are more localized but they too alter the land, cutting into mountainsides and leaving permanent scars. Researching and visiting quarries and other stone producers gives masons a better understanding of where their stone comes from and helps them to choose greener, more Earth conscious vendors.
What sort of building technique is being employed? Drystone construction, in which no mortar is used, is more sustainable than mortar masonry, but not suitable for all projects. Masons who understand the advantages of drystone work and know how and when to properly apply the techniques are in a great position to make more sustainable building choices.
Lime mortar is now making a comeback, in part because of its green qualities: lower carbon production costs, absorption of atmospheric CO2 during curing and the ability to repair itself. Lime mortar is not suitable for all types of work, but should be researched in the planning phase of a project. And of course, whatever techniques are being employed, build it to last.
Really there’s no simple answer to the question “Is stone green?” The choices the mason and project planners make along the way determine just how sustainable the project will be. Local stone installed by skilled craftspeople using sound building practices will create beautiful and strong works that will last generations.