Different builders have different ideas about what actually constitutes a “green building material,” but there are certain standards that most would agree on. Any material that helps builders achieve the goal of improved sustainability by reducing the environmental impact of the building process would be considered green. The Construction Specifications Institute, an authority on the topic of construction specifications, has classified green building materials as follows:
Renewable, natural or plentiful - Natural materials that require no or minimal processing; materials that grow rapidly; renewable resources; sustainably harvested materials–certified by a third-party such as Forest Stewardship Council. (i.e. bamboo, cork and FSC-certified wood).
Locally available – Products that are obtained locally reduce transportation demands and lower greenhouse gas emissions. (i.e. earth used for rammed earth and compressed earth blocks). Some of the products from the previous category, such as bamboo, make ideal building materials, but if they have to be shipped far distances they aren’t all that sustainable. Bamboo is a good example, since it’s mostly imported from Asia. Certain species of the grass can, however, be grown in Canada.
Recycled content – Building materials that are made with recycled content (i.e. papercrete, enviroboard, wood-plastic composite).
Recyclable or reusable – Different than the above—materials that are not necessarily made of recycled content, but can be recycled or reused at the end of their lives (i.e. metals, wood, plastic, glass).
Salvaged, deconstructed, remanufactured or refurbished – Grabbing something before it goes to the dump doesn’t just mean one less product that needs to be disposed of, but one less product that needs to be manufactured (i.e. furniture and fixtures such as cabinets, doors, windows and floors).
Durable – Materials that last longer don’t need to be replaced as often. Some consider non-renewable materials such as plastic to be “green” because of their durability (i.e. stone, copper roofing, hardwood flooring, and any high-quality furniture and cabinetry that lasts a long time).
Resource efficient manufacturing process – Manufacturers who are efficient in their manufacturing process by using less energy, outputting less greenhouse gases and producing less waste than conventional manufacturers.
Any systems, materials and components that reduce energy consumption using renewable energy, such as:
- solar PV systems
- solar hot water heating
- wind turbines
- micro hydro
Materials and systems that conserve and collect water, such as:
- rainwater harvesting systems
- low-flow toilets, faucets and shower heads
- grey-water systems
Indoor air quality
Low- zero-VOC / Minimal chemical emissions – Materials that emit minimal or no volatile organic compounds (VOCs) such as low- or zero-VOC paint.
Low or non-toxic – Materials that emit little or no carcinogens, irritants or reproductive toxicants.
Moisture resistant – By resisting moisture, products inhibit biological growth such as mould and last longer.
Healthfully maintained – Materials that can be cleaned using non-toxic or low-VOC cleaning products.
Health-promoting technology – Devices that assess the indoor environmental quality (IEQ) and enhance air quality, such as monitoring instruments.