The construction industry is responsible for around 40% of the world’s carbon emissions. First, we have the sourcing of materials themselves, such as the equipment involved in harvesting trees.
Then we have manufacturing components, which add more emissions to the mix. Transport from one place to another piles on more carbon release.
Everything leading up to and included in the build is referred to as embodied carbon. Once the home or office is complete, however, we also produce carbon through heating, cooling, and lighting the space. This is called operational carbon.
With this in mind, the most environmentally-friendly construction requires careful consideration of each material used, as well as an emphasis on energy-efficient design.
If you’re taking the time to research the best sustainable building materials for your next project, we’re here to make it easier with some great new products, along with some classics.
What Are Sustainable Materials?
Sustainability is achieving a goal without impacting the natural resources in the process. In the case of green architectural design, this means responsible harvesting or material sourcing in a way that doesn’t deplete those resources.
It can also mean that whatever refinement happens to the materials is done in a thoughtful way, such as minimal processing, production facilities powered by renewable energy, buying local products to reduce transport emissions, and ensuring materials are useful in maximizing energy savings once in use.
Fortunately, innovators around the world are constantly developing new green building materials, which means being educated about sustainable building materials is easier than ever.
If you’re wondering about examples of sustainable materials, think about responsibly sourced bamboo, stone, tile, brick, hemp, and now a variety of bio-based (from plants) products too.
Hemp is a plant. It got a bad rap many decades ago because of its relationship to the marijuana plant.
Now that hemp is once again legal in all 50 states, it’s being used in myriad products from textiles to biodegradable plastic to insulation.
As hempcrete, the fibers are pressed into a material substitute for concrete. It’s renewable, fast growing, and lightweight, so it’s easy to work with and creates fewer emissions during transport.
In plant form, hemp naturally captures carbon from the air and releases oxygen as it grows. That carbon remains trapped inside when it’s converted to hempcrete.
Timbercrete is another wood-based material that can lighten the environmental footprint. It’s a mixture of waste sawdust and concrete, along with a binder.
It’s lighter than traditional concrete and actually traps carbon rather than releasing it.
Timbercrete is a versatile material that can be formed into blocks, bricks, panels, or paver stones.
It can be used indoors or outdoors, is heat resistant (unlike heat-absorbing concrete), and is much easier to screw or hammer into when used as a building material.
Timbercrete is actually stronger than concrete, even though it’s lightweight, and is fire-resistant, unlike traditional wood. It also functions as an excellent insulator, saving energy and money.
3. Composite Roofing Shingles
Every layer of construction materials holds the power to make a difference in the goal of sustainable design. Instead of metal or asphalt roofs, there’s a strong trend towards composite roofing materials.
There are options to choose from, but most are made from a combination of recycled and natural materials such as recycled paper, fiberglass, and asphalt, which are all environmentally friendly and long-lasting.
Composite roof shingles are durable, showing strong resistance to fire, wind, impact, and even natural fading. They are a low maintenance and energy-efficient option too.
4. Insulated Concrete
Insulating concrete forms, or ICFs, are used for building both foundations and above-grade walls. Since they are easy to erect, they’re a versatile product that can be stacked like Legos to reach the desired heights.
They are insulated and reinforced with rebar along the way, so most of the work is in the preparation, before the actual concrete pour.
ICFs are connected together and reinforced as needed before concrete is poured directly into them. After about 24 hours, the frames are then removed and can be reused on another job site.
Similarly, you can source preformed ICF blocks, commonly known by the name introduced in Australia, Thermacell.
The airtight barrier is an aid in passive heating and cooling techniques within the home.
The result is exponentially more energy efficient than wood framing. Plus, the material is fire-resistant and durable against the ravaging effects of natural disasters.
5. Solar Panels
The technology has been around for many decades, but the industry has incurred several generations of product innovations, resulting in solar panels that are lighter, more efficient, cheaper, and easier to install than their predecessors.
At this point in the game, it’s undeniable that solar panels offer significant energy savings and less reliance on power generated by fossil fuels.
6. Eco-friendly Insulation
Glasswool or fiberglass, polyester, cellulose, sheep’s wool, and earth wool are all insulation options. Hemp is also rising in the ranks of efficient insulations to consider.
Cellulose insulation is one of the oldest forms of insulation. This category includes all organic materials such as paper, hay, cardboard, cotton, straw, sawdust, hemp, denim, and corncob, so some of these definitions overlap each other.
It comes in loose-fill and blow-in varieties. It is chemically treated at a rate of around 15%. The chemicals used are not known to harm humans, but repel pests.
Cellulose insulation uses around 85% post-consumer materials and is effective at soundproofing. It’s also very effective at filling even the smallest spaces when blown in. Plus, it’s inexpensive compared to other types of insulation.
Note there are a few challenges with natural insulations. They can settle up to 20%, meaning you may have to add more at a later date or overfill in the beginning. It’s also quite heavy, so it’s not recommended for attics.
7. Smart Glass
The new kid in the glass game is referred to as smart glass. It actually comes in two options. The first is a film you can apply to your existing windows. If they’re in good condition, but you want to boost the efficiency, this is your cat.
The second option is new windows that come pre-treated with the film. The glazing reacts to temperatures inside and outside the home, automatically making the glass darker or lighter to control the amount of light that enters this space.
This technology helps keep the home’s temperature comfortable year-round, and of course, comes with cost savings compared to heating and cooling the home.
It occurs naturally, so it doesn’t require any additional processing. Plus, it’s void of toxic chemicals, is easy to maintain with little care, is durable, and is fire resistant.
Stone also helps to regulate temperatures naturally, which means less energy consumption through artificial HVAC. It’s a perfect material for floors and walkways. Stone is also commonly used for countertops.
Slate, if found locally, is a remarkable roofing material.
Most people think of bamboo as wood when they see it in flooring and furniture, but bamboo is actually a grass—an incredibly fast growing grass—which makes it an endlessly renewable resource.
Unlike wood, which can take decades to hundreds of years to mature, bamboo is ready for harvest in less than five years.
It’s strong, offers an aesthetic appeal, and because it’s lightweight, it’s inexpensive and less impactful to transport.
Cork is one of the most sustainable natural materials on the planet. It’s renewable, recyclable, and biodegradable. It’s also naturally antimicrobial, mold and mildew resistant, a great sound barrier, and a highly effective insulation product.
The cork industry also directly contributes to healthy ecosystems and strong economies.
The process really starts with the cork oak woodlands, primarily located in Portugal. These trees provide a wildlife habitat and a healthy ecosystem for plants and animals.
The best part is that no tree is harmed in the production of cork. There’s no need to cut the trees down.
Cork is sourced from the outer layer of the bark by shaving it away. The tree responds by growing more bark in a regenerative process that actually absorbs 3-5 times more CO2 than unharvested trees.
Cork trees are first harvested after about 25 years and then about every ten years after that. It’s a slow process, but while the trees work to grow cork, they bring myriad benefits to the environment.
Ferrock is made from waste steel dust (we love recycling) and silica from ground glass.
It’s a fairly new material, launching onto the scene in the past five years or so, more than a decade after the initial lab accident that resulted in its discovery.
Reports suggest it’s more flexible than concrete, which makes it less likely to crack. It’s also reportedly up to five times stronger than concrete when it comes to compression. That’s a lot of strength.
Ferrock is carbon negative, meaning it traps more carbon than it releases during manufacturing.
Unlike other materials, Ferrock is strengthened by exposure to saltwater, making it a great concrete substitute in coastal regions.
Plus, Ferrock dries in a fraction of the time of traditional Portland cement.
So far, Ferrock is made in limited quantities, partially due to the fact it relies so heavily on waste products from other industries.
12. Plant-Based Polyurethane Rigid Foam
There’s nothing new about rigid foam as an insulation material, until there is. Primarily it's that the previously wasteful and petroleum-based foam is now being made from kelp, hemp, and bamboo.
The resulting rigid form is ideal for insulation. It’s mold and pest resistant. Plus, it won’t exist on the planet for generations after its useful life in your walls.
13. Straw Bales
Straw is a natural material that has been used as a building material for a long time. People have stuffed their walls with straw with the knowledge it’s a great insulator of both sound and heat. Plus, it’s one of the least-expensive materials you’ll ever find to build with.
Straw bales are pressed from an endlessly renewable material and also help with the carbon emissions problem since it is a plant. Obviously, straw bales may not be the most durable option.
If not properly cared for, they can be susceptible to pests and mold, and don’t offer fire resistance. Also note some insurance companies will refuse to cover a straw-based structure due to fire hazard.
However, with proper protection, a straw bale structure can last a century or more. Better yet, the materials can be easily composted back into the land with no waste.
Beyond traditional straw bales, straw can also be combined with concrete as an aggregate to lighten the carbon footprint of the latter.
14. Sand Bags
They’re for more than flood control. Although sandbag homes do draw from the technique used to build bunkers and dikes.
Also known as Earthbags, they are bags filled with local natural materials. Depending on where you’re building, this can be sand, gravel, clay, rice hulls, and volcanic rock.
Most Earthbags are actually filled with a combination of heavier and lighter materials.
The bags are then stacked, typically beginning with a trench for stability. Once the desired height is achieved, the bags are covered in plaster or stucco.
It’s not an answer for everyone, but may be just what you need in certain locations, for an outbuilding, or for an added sunroom or other space.
15. Ash and Glass
Mixing recycled glass with ash—yes like from a volcano—creates a unique and sustainable product for countertops. However, you don’t have to travel the world to find a recently erupted mountaintop.
A product known as fly ash is commonly used, and it does the modern world a favor since it’s a by-product left behind at coal-burning power plants.
You can use this ash-glass combo in most places where you would traditionally use tile, such as backsplashes, floors, and outdoor walkways.
16. 3D-Printed Construction
It’s here, and it’s being used. Some homes are being built almost entirely from either prefabbed, 3D-printed walls and beams, or are physically printed onsite.
The computerization of the process means little to no construction waste, and it’s easy on the planet, with no wood or concrete to deal with.
Plus, changing the design requires a few keystrokes rather than major architectural and engineering involvement.
17. Interior Design Materials
Once the structure is complete, the focus moves to the interior design. Here too, you can focus on the health of your family and the planet with paints void of VOCs and furniture made without chemicals.
Also avoid the off-gassing from carpets by using those made from natural materials. The same goes for throw pillows, window coverings, area and throw rugs, bedding, etc.
Avoid plastic everywhere. Instead, make or buy ceramic planters, real wood furniture, and accessories made from natural fibers like jute, cotton, hemp, flax, and linen.
Like monitoring healthy foods, be sure you understand the ingredients in the products and materials you use to build and decorate your home.
While you're on topic, check out our related articles Why is it Important to Design a Sustainable House? and Three Reasons to Select Furniture with Sustainable Design.