When considering the attributes of climate-friendly structures, our thoughts often turn to solar panels, heat pumps, heat-pump water heaters, programmable thermostats, and the like. However, construction materials also have a major impact on sustainability. Low-carbon concrete, for example, can greatly reduce emissions that harm our climate.

Concrete is the most popular building material in the world. Made with water, cement, and a sand-gravel aggregate, it is versatile, strong, and durable. Unfortunately, producing traditional concrete is a dirty process. The culprit is primarily cement, typically produced by burning (calcining) limestone at extremely high temperatures. This process releases carbon dioxide gas due to the calcination of the rock and the combustion of fossil fuels to heat the kiln. One estimate holds that if the cement industry were a country, it would be the world’s third- or fourth-largest emitter of the greenhouse gas carbon dioxide.

Introduced in the mid-20th century, low-carbon concrete incorporated alternative ingredients that decreased cement content while improving strength and durability. More recently, the environmental benefits of lowering concrete’s carbon footprint have been recognized, and presently innovators are focused on reducing the amount of cement in the concrete mix, cement’s carbon intensity, and the burning of fossil fuels in the production process. While some products have yet to achieve scale, others — particularly those incorporating type 1L (Portland limestone) cement or supplementary cementitious materials like fly ash or slag — have been marketed for years.

Homeowners can find low-carbon concrete in Maine if they know where to look. For hardscaping needs, including pavers, concrete blocks and so on, a primary option is Genest Concrete’s “price accessible” G-Mix line of products. And while DIYers unfortunately won’t find bags of low-carbon concrete mix locally, the supplier Auburn Concrete, with locations in southern and central Maine, sells competitively priced ready mix for large projects. These well-established products can be expected to meet the standard performance metrics of ASTM International and the Maine Uniform Building and Energy Code.

After water, concrete is the second most widely used material on earth, and lowering its carbon footprint can do much help us live more sustainably without adding cost. So go ahead and build that retaining wall out back using low-carbon concrete products — and if a job requires a professional, ask an experienced contractor to incorporate them.

David Conwell belongs to the nationwide advocacy organization Citizens’ Climate Lobby and is a former member of Brunswick’s Sustainability Committee.