Sustainability and mass timber construction: top of mind and leading edge
Urban expansion, population growth and resource constraints all question the established and conventional delivery of structural systems and the design and construction of our built environments. Indeed, what can sustainable cities look like? Rapidly growing urban centres are putting immense pressure on having an answer to this question. The answer will evolve, but right now, it might be right under our noses!
Our ability to address emerging space and resource constraints and action climate change mitigation in a resilient and sustainable way will be put to the test. Promisingly, this has become a catalyst for new solutions and innovations in the way projects are delivered. It has also sparked a resurgence in both research and popularity of one of our oldest and most reliable building materials: wood.
Mass Timber projects or heavy timber projects have proven to stack up to traditional construction methods in the building sector (Just look outside: steel and concrete buildings are everywhere!) across all factors: cost, productivity, buildability, functionality, and reliability.
With a move towards engineered timber design and mass timber products, the industry can:
- Promote more lightweight, carbon-neutral and natural resources in construction
- Provide a unique alternative to commercial and built environments
- Reduce energy consumption and CO2 emissions
- Create healthier living and working spaces - all central tenets of the UN’s Sustainable Development Goals (SDGs).
Mass timber is getting mass appeal.
By and large, mass timber is here and here to stay, for now at least. Why? Well, it is a tenable alternative to conventional construction and building types. It is also making impressive headway across the whole construction industry ecosystem and has a genuine impact in the competitive marketplace. Simply put, engineered wood products can encompass a wide array of building members and elements from typically low-value but fast-growing softwood trees and turn them into building materials that can rival concrete and steel in strength, durability and commercial outcomes. All this whilst being a carbon-cutting alternative is giving mass timber its mass appeal.
Recent changes to Australia’s National Construction Code (NCC) have streamlined approvals for mass timber structures up to 8 storeys. There has also been a significant market expansion for locally and internationally sourced and produced mass timber products to deliver and support evolving construction types within the Australian market.
Currently, the most common types of heavy timber in use are:
- Glue laminated timber (Glulam)
- Laminated veneer lumber (LVL)
- Cross-laminated timber (CLT): CLT currently shows the most promise for large-scale construction projects. View some examples here!
As international building codes evolve in a space that hopes to build taller but sustainable, we will see timber-frame structures, design, and construction follow suit. For now, we expect national building codes worldwide to drive this trend in 2022 and beyond.
The carbon clock is ticking.
Possibly the biggest draw of mass timber is its green credentials. As governments eventually transition to regulating carbon and supporting CO2 abatement, businesses will follow suit (conversely, companies could put pressure on government) and be empowered and incentivised to move toward a clean energy future. This would likely propel the building sector to research and develop more sustainable construction materials. Currently, the environmental impact from construction is unsustainable. Cement and steel production is highly energy and fossil fuel-intensive, with 7% of global CO2 emissions originating from the steel industry alone and cement production accounting for 8% of total global CO2 emissions.
Furthermore, unlike wood, cement cannot be reused or salvaged. While steel can be multi-cycled, it still requires high-temperature processing. Unlike concrete, steel cannot always be manufactured locally; it is typically transported over significant distances, further contributing to carbon emissions.
The resources we extract and the materials we manufacture for different building types contribute enormously to greenhouse gas emissions. Whilst initiatives have been taken in these industries to improve energy efficiency, difficulties in transitioning towards a lower carbon footprint have made wood construction and mass timber projects compelling alternatives. One can argue that end-of-life disposal of wood products and the need to source timbers cut from forests may not be the most appealing third alternative. However, at this very moment, timber is one of the only renewable construction materials in use today. By its very nature, timber sequesters and removes CO2 from the atmosphere, reducing carbon emissions significantly before and even during construction.
The future can be prefabricated
Adding to its clean record, mass timber construction is a speedy build. Prefabricated and modular construction are emerging as popular design methods in the construction sector. Prefabricated buildings are made up of components and elements manufactured in remote factories, transported on-site, and assembled into buildings. Studies have already shown that productivity will substantially increase by increasing the proportion of prefabricated elements in a construction project. This will result in faster construction, less waste, noise, disruption, and lower unit and operational costs.
There are many benefits to prefabricated mass timbers as well. Prefabricated cross-laminated timbers offer higher dimensional stability and structural integrity than traditional timber-framed systems. Further, the fact that wood is such a lightweight, versatile, and flexible material means that factory handling, transportation and assembly of elements is substantially more straightforward. While direct cost comparisons still have concrete buildings at an advantage over wood buildings, prefabricated timber’s lightweight nature and the opportunity to speed up construction time and optimise erection programmes shifts the cost balance.
We can expect significant workforce upskilling in the mass timber construction market to deliver on the promise of significantly shorter construction programmes (up to 20-50%) and cut schedules due to advances in modular construction types and prefabrication.
In with the old: let’s innovate.
Interest is growing in building tall and pushing the limits of innovation with structural timber. However, timber in construction is far from a new technique, so is a throwback really worth it? Well turns out it can be. Research and advances in material science are looking at wood modifications to address timber’s dimensional stability, durability, fire resistance, longevity and UV sensitivity. The aim is to open up new ways of making timber’s structural performance even more optimised, workable, safe and sustainable. Fracture mechanics, clear-coating processes, prestressed timbers, and timber hybrids and composites are all spaces we are keenly watching.
The construction sector as a whole is at the precipice of significant innovations that are mainly in the form of new design tools such as Building Information Modelling (BIM), 3D rendering software, Augmented Reality (AR), Design for Manufacturing and Assembly (DfMA) and data integration technologies. These innovations themselves further expand the possibilities for mass timber construction and design. These tools aim to find solutions to common and emerging constraints within the construction sector, making room for advances in efficiency, productivity, reliability, safety, and sustainability. They open the door for designers and engineers to address problems in a more integrated way. These emerging and sophisticated approaches could boost its market share and consolidate the fact that timber is indeed well-suited to these new business models.
Wood and wellbeing: time to ‘spruce’ up our living and working spaces.
Humans have used wood as a building material for millennia. Trees play an essential role in promoting biodiversity, reducing the heat island-effect and noise, and cleaning surrounding air and water, even in urban settings. Yet the role of wood as a factor in better health and well-being both in external and internal environments has only been an anecdotal one for a long time. Only now are wood’s biophilic benefits being seriously researched and understood.
Inside our homes, work, or public spaces, access to natural materials like wood has led to decreased occupant stress, greater confidence, and better social integration. A study commissioned by Forest and Wood Products Australia, focusing on the impact of wood in the workplace and on people, found a correlation between employees’ physical, mental, and emotional health and the presence of wood. Benefits included overall worker satisfaction, lower absenteeism, and enhanced productivity. Evidence-based research is making strides in quantifying how people’s access to nature both inside and around the workplace or the home contributes to measurable social and economic benefits.
So, what does this change? Well, quite a lot. If we can quantify how our built environment can improve productivity, efficiency, and overall quality of life, it would significantly impact the building sector and design and construction priorities. Right now, building rating schemes such as WELLs incentivise building designs that promote physical and emotional occupant health. Following that, architects and designers will be encouraged to make holistic decisions based on biophilic design and material choices, which then reverberates engineering design.
What is CalcTree, we hear you say? And what if we said that CalcTree could be the perfect platform to design with mass timber?
We’re a venture-backed Construction-Tech startup, soon to launch the world’s first multi-disciplinary calculation management platform. We help you ensure data, designs, and calculations are always in sync, allowing you to spend more time creating innovative, sustainable, and modern designs.
To learn more, join our waitlist and Slack community today!