We have a problem:
Australia’s construction sector creates nearly one-quarter of our nation’s greenhouse emissions.
There’s plenty of evidence to suggest this is destroying the environment.
In fact, the damage is so extensive, there’s little point in corporate action, right?
It turns out that companies can drastically reduce their ecological footprint by using sustainable building materials, whenever possible.
Green buildings in the US, for example, had already lowered carbon emissions by 34 per cent in 2017, as reported by the National Geographic.
Impressive – but that’s not all.
This is about cutting costs for your business too.
Many sustainable materials are cheaper to use than conventional alternatives. As for those that are more expensive? They usually generate energy savings for the property owner.
Not to mention:
Consumers who care about the environment are drawn to businesses that share their values.
It turns out that most people are passionate about corporate sustainability, according to a survey by research firm Nielsen.
“A whopping 81% of global respondents feel strongly that companies should help improve the environment”.
This article explores a handful of ecological building solutions that could save your company money, as well as ease environmental pollution.
Nine sustainable building materials
1. Green thermal insulation
Polyester, sheep’s wool, cellulose and earthwool.
What do these materials have in common?
They help to lift the energy rating of buildings, by trapping excess heat in winter and keeping it away in summer.
This reduces the need for energy-intense forms of temperature control, such as air-conditioning, which in turn keeps electricity bills down.
You could probably say that most forms of insulation are eco-friendly, for this reason.
However, some are greener than others, so to speak.
Many people use fibreglass insulation because it’s cost-effective, however the manufacturing process uses up to 10 times more energy than sustainable alternatives.
There are better options:
- Sheep’s wool: This is probably as natural as it gets, off the back of a sheep. Harmful particles in the air are absorbed by this material, which doesn’t burn easily or itch the skin. It also doesn’t degrade as fast as materials like straw and can be harvested quicker than some other natural insulators, like cotton. It’s not the cheapest sustainable insulation option though!
- Cellulose: This insulation consists of recycled newspaper and other types of paper that would otherwise end up in the rubbish tip. On the downside, this isn’t the easiest material for firefighters to manage in emergencies.
- Polyester: Recycled plastic bottles can be found in this product, which can also be recycled. It’s non-flammable and doesn’t cause itchy skin or release dust particles.
- Earthwool: There are no artificial colours in this product, which contains natural bio-based materials and inorganic glass fibres.
- Plant-based polyurethane rigid foam: This foam is made out of natural materials such as bamboo, hemp and kelp. The product resists heat extremely well and insulates better than fibreglass, due to its higher R-value.
- Straw bales: You probably wouldn’t expect straw to be resistant to fire (or vermin and decay for that matter), but it is. Many Australian buildings feature strawbale walls that are rendered with cement or earth. Straw comes from grass, so it’s a renewable building material that’s easily harvested. Cost effective, strong thermal insulation, sound insulation, moisture resistant and safe – straw bales tick all of the boxes.
Keep in mind:
Whatever material you choose, there’s no sense in slapping it in place and hoping for the best. Insulation doesn’t perform effectively if installed poorly, which defeats the purpose.
2. Structural insulated panels
A structural insulated panel (SIP) consists of a piece of foam that’s placed between layers of plywood, strand board and cement. Floors, walls and ceilings can be constructed using these durable engineered panels, instead of conventional framing lumber and insulation.
The benefits for architects, designers, builders, residents and property owners?
- SIPs are stronger than traditional wood framing types
- Less waste from the prefabricated approach
- The general consensus is they conserve around 50 per cent more energy, resulting in lower bills for property owners or residents
- They can be combined with other building materials, lending more creative freedom and versatility to design
- Higher upfront cost but shorter construction times and lower labour costs than traditional framing
- Builders don’t require specialised tools to install SIPs
- A high level of airtightness in buildings, which means reduced drafts and less heat transfer
- Strong soundproofing qualities
3. Recycled metal
Builders rely heavily on metals such as aluminium and steel, which are durable, lightweight and versatile.
But there’s a challenge:
A lot of energy goes into mining and manufacturing the metal, which takes its toll on the environment. Keep in mind, ore is a finite resource that already shows signs of being in short supply.
Recycling provides a feasible alternative, by lowering the energy used in the overall manufacturing process.
And the best part?
Metals keep their properties, even after being recycled multiple times – that’s an infinite number for aluminium and steel!
This means that 75 per cent less energy is used every time that steel, for example, is repurposed.
“If you think of the whole thing like a cycle from the raw extraction to the processing to the installation to the demolition to the disposal, when you get to recycling you basically cut out the whole raw extraction and processing.”
Mike Stopka from the Delta Institute, quoted in Smart Cities Dive
There are other practical benefits to consider too:
Recycled metal tends to be strong, durable and long-lasting, as well as water and pest resistant. It doesn’t need to be replaced frequently, so it can be used to construct roofs, bridges, roads, building facades and roofs.
4. Reclaimed wood
Recycled wood that’s been properly treated is useful for building walls, cabinetry, decks, floors, beams, panels and other structures.
It’s usually sourced from old-growth trees, which makes it sturdier than virgin wood that comes from first-generation forests.
As with recycled metal, reclaiming wood significantly reduces the amount of energy that’s used to make it. It also stores carbon and lowers the demand for fresh timber from forests.
And of course, there’s a certain aesthetic charm that appeals to architects who desire a rustic and ecological design that only occurs when wood ages over time.
However, wood is vulnerable to being degraded by pests and insects, so it’s important to carefully inspect every restored piece.
5. Engineered wood for cross-laminated timber buildings
Engineered wood contains different wood types that are bound or fixed together, as opposed to solid pieces of wood from a single source.
Entire buildings are being built to heavily feature this material, that’s how cost-effective and sustainable it is.
In fact, Australia’s tallest engineered timber office building recently opened in Brisbane’s Fortitude Valley. The floors and walls are made from cross-laminated timber (a form of engineered wood, also known as CLT).
Why engineered timber?
- Builders work faster with it, which saves money on construction time
- Excellent strength and stability
- Decent fire resistance
- High thermal and insulating properties
- More flexibility with design
- Less waste on building sites, since the panels arrive prefabricated
- Strong and durable
- Resists moisture well
The environmental benefits are impressive too.
Global carbon emissions could be reduced by up to 31 per cent if more buildings were constructed with wood, rather than concrete and steel. This is according to a 2014 study by the University of Washington and Yale.
However, it’s worth noting:
Some forms of engineered wood may release chemicals and solvents into the air (off-gassing), which raises health concerns.
Ask your manufacturer directly about their approach, as certain companies are careful to use ingredients that don’t do this.
6. Precast concrete slabs
Concrete slabs arrive at the construction site fully formed, having been mixed and set into blocks by the manufacturers.
A lightweight filler, such as foam insulation, is usually sandwiched between the outer layers.
Prefabrication occurs in a controlled environment, so there’s less chance of cracks and structural faults forming in the concrete.
Precast concrete slabs are extremely durable, withstanding all kinds of weather conditions. This affordable building material is often used to construct walls and building facades, for this very reason.
As far as sustainability goes:
Producing and assembling the slabs takes less energy than many conventional concrete types, making this a greener option. The concrete also helps to control heat, which saves money for property owners who don’t need to use the air conditioner as much.
Bamboo has a long history as a building material, stretching thousands of years. Lightweight, durable and renewable – it offers the best of many worlds.
Fast-growing around the world, there’s no need to replant bamboo after harvest and it self-generates at an impressive rate.
As for construction performance:
This perennial grass has more compressive strength than brick or concrete, so it’s well-placed to bear heavy loads and withstand harsh conditions over time.
It’s commonly used as a sustainable building material for scaffolding, bridges, flooring, structures and cabinetry.
Be mindful though:
Untreated bamboo attracts insects and swells when exposed to water, so it needs to be treated to prevent this.
Another natural resource that grows quickly, cork is harvested from bark on a tree that continues to grow.
Not only is this recyclable and renewable resource hard-wearing, it’s also lightweight.
NASA even uses cork as an insulator, thanks to its excellent thermal properties.
More companies are using cork for the external cladding of buildings, as it’s fire retardant, resists abrasion, reduces sound pressure and creates an earthy and natural aesthetic.
9. Cement made out of recycled plastic
Engineers have found a way to create durable, light-weight and flexible concrete, using plastic waste as a key ingredient.
Construction companies around the world are building recycled plastic roads, footpaths and houses with this material.
One example in Australia:
A road in the Sutherland Shire is made out of an asphalt mix that contains recycled plastic waste and glass.
This is a cost-effective solution because plastic concrete is often cheaper than traditional mixes. Builders are more productive with these lightweight materials – saving money on transportation and labour costs.
Environmental benefits of building with plastic concrete:
- Less landfill
- Lower carbon emissions
- Water savings
Recycled plastic cement also performs very well:
- Resists chemicals and solvents
- 10 to 40 per cent lighter than conventional concrete
- Easy to reshape thermoplastics
- Strong thermal and sound insulation
- Prevents energy leakage
- Fire-resistant (depending on the plastic material used)
- Durable and long-lasting
- Withstands extreme temperatures and heavy loads
Become a business that’s part of the solution…
The global building industry consumes 36 per cent of the world’s energy, according to the IEA.
But it’s possible to improve this, drastically.
We’ve seen construction projects reduce their greenhouse emissions and energy demand by using sustainable building materials.
“The Building Sector has the largest potential for delivering long-term, significant and cost-effective greenhouse gas emissions.”
United Nations Environment Programme
More businesses should take note and follow suit.
To help the greater good, yes, but also to serve their own interests:
- Cut production time and building costs, while maintaining high performance
- Help clients to save money on their electricity bills
- Attract consumers who care about the planet (a growing number of people)
It isn’t enough to adopt isolated green strategies, if Australia has any hope of meeting targets set by the Paris Climate Agreement.
“An effective strategy to cut emissions must encompass the whole lifecycle of planning, designing, constructing, operating and even decommissioning and disposal of buildings. A holistic vision of sustainable building calls for building strategies that are less resource-intensive and pollution-producing.”
Consider becoming part of the green building movement that’s being coordinated on a global scale. The goal of Advancing Net Zero is to support the construction of buildings that are highly energy efficient.
Read more about getting certified with the Green Building Council of Australia.