stone

Environmental Impact Rating

Harvesting — Negligible to Moderate

Stone is a non-renewable but abundant resource. Some naturally occurring stone can be harvested directly from the surface of the ground on the building site. Most commercially available stone is quarried from established pits, where it is mechanically extracted. Impacts may include habitat destruction and ground and surface water contamination. Stone may be usable directly from the quarry, or may require further cutting and shaping.

Lime and/or cement for mortars are made from quarried limestone. Impacts can include habitat destruction and surface and ground water contamination.

Sand for mortars is quarried with low impacts.

Manufacturing — Negligible to Moderate

Stone may require little to no manufacturing after harvesting, as some stone will be suitable for building walls in its naturally occurring state. Other stone will be quarried in large pieces and then sawn or split into shapes that are suitable for cladding. These processes are not very energy intensive and typically have minimal impacts that can include release of silica dust and water contamination.

Mortar ingredients require heating of limestone to high temperature, with resultant high fossil fuel use and emissions and impacts including air and water pollution.

Transportation — Negligible to High 

Sample building uses

As a heavy material, the transportation impacts of stone will increase with distance from harvesting and manufacturing source.

Installation — Negligible

Waste: Low

Compostable — Stone may be left in the environment or used as aggregate or fill.

Recyclable — None.

Landfill — Bags for mortar ingredients.

Chart of Embodied energy & carbon

Energy Efficiency

Stone is most commonly a rainscreen cladding and does not act as the primary air control layer. The thermal mass properties of stone walls may help to moderate temperature swings, especially in indoor applications, but stone walls have no appreciable thermal control benefits.

If stone is being used as a structural wall, it may be difficult to make the wall air tight due to the number of joints and the variegated surface of the stone. Another form of primary air barrier (plaster coating, sheet material) may be necessary to make the wall airtight and efficient.

Material costs: Low to high

The source of stone and the degree of manufacture to shape the stone will greatly influence the price.

Labour Input: High

Site-harvested stone can be very labor intensive, including the digging, lifting and sorting of a heavy material. The wall requires preparation including the fastening of ties. Laying the walls requires the mixing of mortar, laying of stone and finishing of joints.

Health Warning

Stone cutting and mortar mixing can cause exposure to high quantities of silica dust, so proper breathing protection is required.

Skill level required for homeowners

Preparation of substrate — Easy

Wall framing and sheathing skills are required. The process of measuring and fastening stone ties is straightforward.

Installation of sheathing — Difficult

There is a lot to learn in order to successfully install stone cladding. Skills required include marking and measuring for courses, mortar mixing, laying mortar and stone and creating appropriate headers/arches for openings. The varied nature of stone requires aesthetic decisions while laying stone. Without prior experience or practice, stone masonry may best be left to professionals.

Finishing of sheathing — Easy

Jointing between the stones is the only finish required once stone is installed.

Sourcing & availability: Easy to moderate

Natural stone is available directly from quarries and through masonry supply stores. Mortar materials are available from building supply centers and masonry supply stores.

Durability: Very High

Stone cladding and walls will last for hundreds of years, with the mortar joints being the weakest element. Proper attention to maintenance of mortar joints (every ten to twenty years) will greatly extend the lifespan of a stone wall.

Code compliance

Stone is an acceptable solution in some codes. Though stone construction has a lot of historical precedent, the use of natural stone in modern construction is rare enough that some codes no longer directly reference it as an acceptable solution. There are sufficient published standards to make a reasonable case for its acceptance as an alternative solution in these jurisdictions.

Indoor air quality: high

Used indoors, natural stone is unlikely to have a negative effect on IAQ. The exception would be stone that emits radon gas, a naturally occurring radioactive gas associated with some types of granite and limestone in some regions. Radon gas is a serious contaminant with carcinogenic properties.

Resources for further research

Gallagher, A. Robert., Joe Piazza, and Sean Malone. Building Dry-Stack Stone Walls. Atglen, PA: Schiffer, 2008. Print.

McRaven, Charles. Building with Stone. Pownal, VT: Storey Communications, 1989. Print.

Long, Charles K. The Stonebuilder’s Primer: A Step-by-Step Guide for Owner-Builders. Willowdale, Ont.: Firefly, 1998. Print.

Cramb, Ian. The Art of the Stonemason. White Hall, VA: Betterway Publications, 1992. Print.

McRaven, Charles. Stonework: Techniques and Projects. Pownal, VT: Storey, 1997. Print.

McRaven, Charles. Building Stone Walls. Pownal, VT: Storey, 1999. Print.

Flynn, Brenda. The Complete Guide to Building with Rocks and Stone: Stonework Projects and Techniques Explained Simply. Ocala, FL: Atlantic Group, 2011. Print.

Future development

Stone wall construction is unlikely to experience major changes or innovations, as the system has been refined over centuries and the raw materials are largely unrefined. In regions where appropriate stone is available, the costs of natural stone may become more favorable compared to manufactured alternatives as the price of fuel rises. However, the high amount of labor and skill required are likely to keep stone wall construction to a small portion of the overall market.