As the demand for new homes and buildings increases along with population growth, so too does our impact on the climate. According to a 2020 report conducted by WWF Australia, the built environment sector is responsible for one quarter of Australia’s emissions, with the steel and cement industries representing around 7% of global emissions. With the climate already in crisis, it’s clear that we need to find a more sustainable way to build, and fast.
There are many aspects that contribute to the carbon footprint of the construction industry, from production and distribution of materials, to the materials themselves, which is why a multifaceted approach is required if we are to see real and meaningful change. One aspect that is sparking plenty of interest and excitement in the industry currently is the potential for timber, in particular mass timber, to replace steel and concrete in the construction of buildings.
So is mass timber a viable and more sustainable way to build? In this article we take a closer look at some of the key considerations for architects, builders and homeowners who are designing, constructing and living in the buildings of the future.
What is mass timber?
Unlike standard stick timber that is cut into lengths and used for framing, mass timber is made up of multiple layers of timber that are stuck together to form larger panels or beams. Short for ‘massive timber’, mass timber is the term that’s used to describe a range of timber products that are made this way, including lumber glue laminate (LGL), laminated veneer lumber (LVL) and cross-laminated timber (CLT). Mass timber is generally made from softwood species such as
pine, spruce and fir, but can also be manufactured using some hardwood species like ash, birch and beech.
Watch the video below explaining the mass timber products and benefits when compared to concrete and steel.
Why is mass timber a great choice for homes?
All larger YZY granny flats are constructed entirely from laminated LGL timber that has been manufactured into precision cut parts for our kit homes. There are some key reasons why we work exclusively with it, which we’ve outlined below.
- Structure and strength – LGL is the ideal fit for our tongue and groove interlocking design system, as it provides both structure and insulation. The structural strength of LGL timber is comparable to concrete and steel, remaining straight, stable and strong, even in harsh outdoor environments.
- Negative carbon footprint – A big plus of mass timber over traditional materials is that unlike steel and concrete it does not have a high carbon footprint. In fact, when sourced from sustainable plantations and manufactured and built efficiently, it is more likely to have a neutral or negative carbon footprint. We have an article ‘Here’s Why Timber Homes are a Sustainable Choice’ with interesting figures on how much tonnes of carbon can be removed when building with timber.
- Built-in energy efficiency – One of the things we love most about working with mass timber is that the solid timber walls of our homes act like thermal batteries, storing heat through the day before gradually releasing it at night. This creates a more stable temperature and avoids substantial temperature changes, which in turn reduces the need for artificial heating or cooling. You can read more about this in our article How Energy Efficient Are Solid Timber Homes?
- Fast and easy to work with – Because mass timber is manufactured offsite, it can be crafted into parts of almost any shape and size, making it easier to transport, handle and build with.
What’s more, many manufacturers of mass timber use computer numeric control (CNC) machines which allow for precise cuts every time. This means that when timber arrives on site, it is pre-cut and ready to construct without the need for time consuming on-site adjustments.
- Performs well in fire – A common misconception is that timber homes are highly flammable. And while stick built frames and some timber materials might ignite and burn easily, mass timber is quite a different story. The air tightness and density of mass timber makes it perform differently, with the outer layer charring, but then extinguishing, protecting the inner layer from damage. This works in a similar way to how a large timber log behaves if you hold a match to it – it is extremely difficult to get it to burn.
- Solid timber is strong in earthquakes – Another big plus of mass timber is its structural strength. It can withstand high winds and exposed sites, and its performance in earthquakes has been extensively tested and it has proved to be remarkably strong. Watch video below or read an article about the test performed in Japan, simulating an earthquake magnitude 7.3 in Richter scale.
- High resistance to floods – In general, if a conventionally built home is subjected to a flood, large sections of Gyprock will need to be replaced as a result of the water damage. However, a solid timber home will dry out once the water subsides and remain structurally stable, saving you the added cost and inconvenience of repairs.
- Wood creates a healthy home – There is something calming and comforting about a home that is built from natural wood and you can feel the connection to nature. It is not only aesthetically pleasing and good for your spirit, it’s healthier for you and your family too. Interestingly, a report by Planet Ark found that timber interiors have numerous benefits to our health – from improved air quality by moderating humidity, to lower blood pressure and reduced stress levels.
The time for change is now
With the mounting pressure from the public on climate change action, now is the time for the construction industry to step up and reduce their carbon footprint. There are many touchpoints where positive change may occur, however, the clear benefits to the environment and our health and wellbeing suggests building with mass timber is a great place to start.
With the National Construction Code currently undertaking its three yearly review, there have been many submissions from both the public and those in the industry calling for the required standards of sustainability in new homes to be lifted. This is a fantastic opportunity to create sweeping positive change across Australia, and we are hopeful that the 2022 update will incorporate the suggestions that will guide the industry towards significantly lowering their collective footprint.