The COVID-19 epidemic has created a massive slowdown in the global economy, resulting in a rapid reduction in demand for housing and construction across the globe. This pause in the global construction industry has stimulated a growing discussion about kickstarting a new age of architectural innovation, with timber products at the helm of the ‘Building Back Better’ movement.
Timber is a fantastic building material and, if sustainably sourced, a vital tool in combating the climate crisis. Although chopping down trees may seem a bad way to reduce CO2 emissions, this cannot be further from the truth.
What Makes Wood Such a Good Building Material?
In construction, timber is far more environmentally beneficial and economical than typical materials like concrete, plastics and steel, as it acts as a vital carbon store and requires far less manpower and machinery to erect. This is largely due to the option to import ‘flatpack’ wooden templates made out of Cross Laminated Timber (CLT), which can be used like Lego to quickly and efficiently create large structures.
Wood products, despite being lightweight, outperform steel in tensile strength, allowing designers more freedom to create beautiful open plan buildings utilising the wide availability of differing species, without overcrowding spaces with structural supports1.
Timber also outperforms plastics and steel when it comes to energy efficiency. Due to wood’s cellular structure, the material is a far better insulator than typical building materials, requiring far less energy to maintain thermal regulation1.
Understandably, a major concern around the increasing use of timber in construction is the material’s flammability. However, innovation in the timber market and improvements in wood treatments have already made it possible to create aesthetically pleasing, safe and sustainable buildings.
“The fact is that wood has many fire safety benefits compared with other materials. Take steel, for example, which certainly doesn’t burn, but it does soften and lose its structural integrity. Although wood is flammable, it burns in a controlled and predictable way. Wood also retains its load-bearing capacity for a long time, even during a fire.”
BIRGIT ÖSTMAN, SP Technical Research Institude of Sweden
New techniques of treating wood to make the material far more fire retardent are coming to the forefront, such as the use of sericrite and metal foils to isolate layers of wood, allowing for slower burn rates. Additionally, efforts to maintain the silicon layers in wood via the application of nanocomposite coatings reduces flammability2.
To learn more about sustainable wood and its benefits of a building material follow this link.
Burry Port Primary School Project
In the UK, attempts to build back better are already fast underway with the completion of several experimental projects, such as the renovation of Burry Port Community Primary School in Carmarthenshire Country Wales.
There is no better environment than a school to demonstrate the exciting opportunities that wood provides for designers and architects, whilst also highlighting the environmental and aesthetic benefits of timber to the next generation.
The £3.8 million project was pioneered by the London based Architype group in partnership with Canarthenshire Country Council, with the main aim being to “celebrate Welsh materials and embrace innovation”3, with a particular focus on sustainable construction methods.
The design for this all-wood project, blends together the old and outdated concrete buildings with new and exciting Welsh larch clad open plan classrooms, surrounding a central multiplay/breakout space4.
New methods for wood construction are scattered throughout the build, with the use of softwood panelling and frames, secured by hardwood dowels which utilise air moisture to expand and solidify the frame3.
The use of new building techniques and wood in the interior matches that of the exterior. With the use of magnesite-bound pine and spruce panelling allowing for a toxin-free, healthy environment for children to enjoy working and playing in.
The environmental benefits of using a local product such as Welsh larch are clear, but the advantages of using this particular material are much more numerous:
- In the next several years there will be large quantities of larch available for construction due to the many replanting projects initiated in Wales in response to the recent Phytophthora ramorum epidemic5.
- Larch has been machine graded for strength and typically maintains a rating of up to C27 – meaning it has a bend strength of 27 MPa6. This testing is conducted with the use of x-rays which detail the wood density and knot positioning of timber 7.
- Building alongside larch gives designers far greater freedom to use natural light, with the ability to put in place larger windows around the wood paneling. The use of natural light is proven to provide numerous health benefits, such as reducing stress and increasing productivity.
Conclusion
Projects such as Burry Port Community Primary School, demonstrate the ability of wood to become the go-to material for the builders and architects of tomorrow. Locally sourcing sustainably managed timber is the most environmentally friendly method to create cost-effective and aesthetically pleasing housing. However, for this to become more widely recognised an increased understanding of forest management will be vital in encouraging more projects such as that in Burry Port.
Perhaps the most promising step taken by any country has occurred in France, with President Macron’s announcement that all state-funded buildings must contain at least 50% wood by 2022. The implementation of such a policy has been instrumental in changing designer opinions towards wood and seeing it as a green material.
If the climate crisis is to be effectively mitigated, countries must begin to substitute concrete, steel and plastics for sustainably and responsibly sourced timber products. In doing so, not only will countries reduce their emissions from the construction industry and create vital new carbon stores, but they will also be helping developing nations recover from the economic fallout of the COVID- 19 epidemic by providing new export markets for their timber.
- Loffer, L., (n.d.). The Advantages of Wood as a Building Material. Wagnermeters[↩][↩]
- Lowden, A.l. & Hull, R.T., (2013). Flammability behaviour of wood and a review of the methods for its reduction. Fire Science Review 2. Article number:4.[↩]
- Burrel, E. Mikurcik, G. Dixon, H., (2016). Burry Port Community Primary School. ArchitypeUK.[↩][↩]
- Burrell, E. Mikurcik, G. Dixon, H., (2016). Burry Port Community Primary School. ArchitypeUK.[↩]
- Woodknowledge Wales., (2017). Welsh Softwoods in Construction.[↩]
- Engineering ToolBox., (2011). Softwood and Hardwood – Structural Strength Classes. https://www.engineeringtoolbox.com/structural-softwood-strength-classes-d_1804.htm[↩]
- Ridley-Ellis, D., (2019). A quick summary of timber strength grading. Centre for Wood Science & Technology. Edinburgh Napier University[↩]