Build Sustainably with Timber Frame and Lightweight Construction
Timber frame construction has been gaining popularity in recent years as a method of building sustainable and energy-efficient homes. Estimated percentages of new homes built of timber frame are in the USA approx 35%, Canada approx 65%, the UK approx 25 % and Australia and New Zealand approx 55%. And in the EU, while varying significantly from country to country, on average it’s estimated to be around 55% of all new homes, with Sweden and Finland leading at over 80% and Germany and Austria over 70% of all newly built homes in timber frame. Overall, the use of timber frame construction is growing in popularity in the EU due to its efficiency, sustainability, and cost-effectiveness. Additionally, many countries in the EU have strict building codes and regulations that encourage the use of sustainable and energy-efficient building methods.
In South Africa, the use of timber frame construction in residential building is not as widespread and only accounts for a relatively small percentage of new homes, with majority of new homes still constructed using traditional masonry techniques. This is likely due to a combination of factors including cultural preferences, the prevalence of other building materials, and relatively less expensive labour costs compared to the developed world. However, the interest in and use of timber frame construction is slowly growing in popularity in South Africa and may become more widely used in the future. South Africa recognizes timber frame construction as an approved standard building system, and when constructed in accordance with the SA National Standards SANS 10082, it is considered to meet the requirements of the National Building Regulations.
For those not familiar with timber frame construction, it’s important to note that a timber frame home does not necessarily have to look like a ‘wooden’ home. The timber frame refers to the structural system used to build the walls, and there are many options of cladding the walls externally, including fibre cement shiplap cladding (often referred to as a ‘Nutec’ house in South Africa ..which is akin to calling a vacuum cleaner a Hoover, as Nutec is just a brand name one of many cladding products available), smooth plastered cladding, as well as wooden cladding as an option. Internally the walls are typically clad with gypsum board and then skimmed smooth and painted, so look no different to a conventional masonry built home.
In addition to timber frame, there are also other methods of timber construction, including Post and Beam construction (included as a standard building method in SANS 10082) and Cross Laminated timber (CLT) construction. Post and Beam often combines timber with large glazed panels (visit https://www.huf-haus.com/en-uk/ for an example from the market leader in post and beam construction in the EU and UK). CLT, which has been available in the EU since the 1990s, has been growing in popularity, particularly for low-rise (3 to 4 story) residential and commercial buildings. This is because it offers efficiency, sustainability, and the capacity to create large, open spaces with minimal structural elements. (see https://xlam.co.za in Cape Town, who are leading manufacturers of CLT systems in South Africa)
Collectively these building systems, along with light steel framing (LSF) (which is similar in construction method to timber frame construction, only that the framing is steel instead of timber – and I’ll discuss the pros and cons of each for various applications in a future post) are referred to as ‘lightweight construction methods’ as well often fit into the category of construction called ‘modern methods of construction’ (MMC).
Lightweight construction refers to building methods that use materials that are lighter in weight than traditional masonry materials like brick, stone, and concrete. The advantages of lightweight construction over traditional masonry methods include:
- Speed of construction: Lightweight construction methods can be faster to construct than traditional masonry methods, reducing the overall construction time and minimizing disruption to the surrounding area.
- Improved energy efficiency: Lightweight construction systems typically have good insulation properties, reducing heat loss and improving energy efficiency. And in the case of timber frame construction and LSF they have hollow walls, which are filled with insulation.
- Flexibility in design: Lightweight construction materials can be cut and shaped to fit a wide range of architectural designs, offering greater design flexibility than traditional masonry methods.
- Improved sustainability: Lightweight construction materials made from sustainable resources reduce the environmental impact of construction projects.
- Reduced weight on the building foundation: Lightweight construction materials place less weight on the building foundation than traditional masonry methods, reducing the need for extensive and costly foundation work. On steep sites, conventional foundation systems become relatively more expensive the steeper the site, whereas lightweight systems with suspended floors are less effected by steep sites with regards costs.
- Cost savings: Lightweight construction materials are often lighter and easier to handle than traditional masonry materials, reducing the cost of transportation and labour. This becomes particularly relevant on harder to access sites, such as remote or mountainous areas and islands.
These advantages make lightweight construction a popular choice for modern building projects, offering improved performance, efficiency, and sustainability compared to traditional masonry methods.
The term ‘modern methods of construction’ (MMC) refers to building methods using prefabricated systems, such as the use of pre-manufactured components that can be quickly and easily assembled on site, and modular systems, typically with factory built modules or ‘pods’. All of these offer benefits such as increased speed, reduced waste, improved quality control, and, for larger projects, lower costs compared to traditional building methods.
Timber frame construction includes all of the advantages of lightweight construction, and can efficiently serve as a prefabricated system (MMC). It has additional advantages over CLT and Post and Beam, in that it’s likely to be more cost effective, particularly for building homes, hence its popularity in most of the developed world over other systems. There are also plenty of dedicated specialist timber frame builders in South Africa to choose from.
CLT, however, has additional structural advantages, and is likely to grow in popularity and for buildings with large open spans and multi-storey construction.
Furthermore, opting for more timber instead of masonry and concrete within any timber construction system represents a more sustainable choice, as timber is a renewable resource that we can source from sustainable forests. (I’ll also do a later post on the environmental benefits of using more timber over other materials).
In conclusion, timber frame construction is a sustainable and efficient method of building homes, offering many advantages over masonry construction and other types of timber construction. Whether you are building a new home or renovating an existing one, consider the benefits of timber frame construction and see if it is the right option for you.