Andrew Orriss of the Structural Timber Association explores the vital importance of timber in construction on the path to net zero, but also the associated importance for specifiers of quality assurance and competency
In recent decades timber has faced greater competition from other construction methods and materials. However, for the UK to meet its net zero 2050 commitment, carbon savings must be made in the construction industry, which is responsible for almost 25% of carbon emissions in the UK.
Carbon accounting benefits
As part of these efforts, the Future Homes Standard regulations are becoming much more stringent, meaning that alternative materials such as timber are appealing thanks to low embodied carbon, low energy in use, and proven design qualities. Structural timber systems offer clear sustainability advantages, while also offering greater versatility, flexibility and construction speed when compared to other traditional construction materials.
A keen focus must be placed on the energy efficiency of new homes and buildings, and ensuring high levels of airtightness and insulation are essential. Structural timber systems offer a straightforward route to achieving these objectives and the use of both timber open and closed frame and Structural Insulated Panels (SIPs) offers excellent flexibility to increase the thermal insulation of the external wall construction. For example, closed panel timber frame systems can typically achieve U-values as low as 0.10 W/m²K. Additionally, the controlled factory conditions under which offsite systems are manufactured allows high levels of precision and means that when the panels are assembled on site, they form a highly airtight, energy-efficient building envelope.
Maximising the use of timber in the construction of new residential and commercial buildings is a simple and effective way of achieving a substantial reduction in carbon emissions. For every cubic metre of timber used in construction, 0.9 tonnes of CO2 is sequestered and stored for the lifetime of the building. And typically for every farmed tree, a further five are planted in its place.
Durability is also a critical component of sustainability that generates an overall reduction in waste. Structural timber systems are more than capable of meeting service-life objectives. To deliver building longevity, a systematic approach to procedures is recommended to engage professionals to review durability as a wider topic throughout the building process. Best practice should always be adhered to for the planning, designing and construction of buildings, and then maintained by those with a solid foundation of understanding of the building material. A moisture management strategy for building projects provides a clear pre-build plan and focuses attention on design and installation.
Health & wellness
Expanding the use of timber throughout a building can also have a number of health and well-being benefits. It is shown to improve both physical and mental wellbeing, and reduce stress. A study conducted by the University of British Columbia and FPInnovations found that the presence of wood surfaces in a room lowered sympathetic nervous system (SNS) activation, which is the system responsible for physiological stress responses. Timber is also linked to benefits in terms of blood pressure, digestion and healing.
A person may feel good about living in a home constructed of natural materials. In a study conducted by the BRE, 62% of respondents saw climate change as an issue they should be concerned about and 96% said that they had already made changes to be more sustainable. Additionally, 43% said they would prefer to buy or rent a home that had a sustainability certification. In fact, approximately one in five were prepared to pay more for such a property.
To deliver durable buildings and reach net zero by 2050, quality of construction is paramount. Across the construction sector, the importance of quality assurance schemes cannot be overstated.
Timber presents our best opportunity for meeting the UK’s net zero commitments by 2050, but the quality and standards of timber construction must be to the highest degree, as will the scrutiny that it is put under. Therefore, accreditation is crucial to providing investors and insurers with evidence that companies are being held to high standards.
Andrew Orriss is director at the Structural Timber Association