This post is the first in our Super Natural Materials series.
Timber: a popular choice
Timber is one of the most popular building materials and people have been building with timber since ancient times. Its great versatility means it’s used in all areas of construction, architecture and design – from structural frames to finishes to furniture and artwork. Timber may be the only material where you could design a whole house with every element made out of timber. We believe it’s one of the very best materials, so we utilise it in the majority of our projects.
Wood is the oldest building material, yet development of Cross Laminated Timber (CLT) has given it a whole new innovative appeal. As Rethink Wood explain:
Cross-laminated timber (CLT) is a wood panel typically consisting of three, five, or seven layers of dimension lumber oriented at right angles to one another and then glued to form structural panels with exceptional strength, dimensional stability, and rigidity. ... Since CLT panels resist high racking and compressive forces, they are particularly cost effective for multi-story and long-span diaphragm applications.
The twin trends of population growth demanding greater urban density and more concern about sustainability, mean timber is getting ever more popular as a building material – even for high-rises. As this story in Popular Science puts it:
The world’s urban future may just lie in its oldest building material.
We're going to outline why it's such a great material, and then offer a few examples of the diverse range of buildings that can be built with timber.
Benefits and strengths of building with timber
To learn more about the benefits of building with timber, check out our previous article ‘13 Ways Sustainable Timber Is The Best Construction Material’. Here’s our top 5:
As well as being naturally beautiful, wood is also extremely versatile. Different species of tree produce timber of differing colours, textures and functional qualities. Wood also competes with plastic in its enormously wide range of applications: from structural frames to exterior cladding and joinery, and from decorative finishes to furniture.
Timber is a highly durable material. Some well-made wooden structures last for centuries, such as the timber frames of many Tudor buildings. It is also easy and cheap to maintain compared to other materials, especially if you don’t mind it changing its colour over time. As a very strong material with good structural properties, it's suitable for up to eight storey buildings (and new innovations are now even allowing timber to be used for high-rises!) It also has good fire resistance. This sounds surprising, but it burns in a much more predictable way than steel – which dramatically collapses after a ‘flash point’ is reached.
In its natural state wood is completely non-toxic and healthy. It can sometimes be treated with toxic preservatives which can off-gas and prevent the wood from being safely burnt or composted, although this isn’t strictly necessary and with careful specification of durable timber, wood can often be used untreated. Advances in green chemistry mean more non-toxic glues and preservatives are being developed all the time. Even ‘conventional’ chemicals have been improved in recent years so off-gassing is now minimal.
4. Carbon Storage
With sustainable forestry, at least as many new trees are grown than are harvested. As long as a timber product does not burn or rot its carbon stays ‘locked up’. So when trees are harvested, their carbon is stored in timber and they are replaced by new young trees, therefore the net effect is removing carbon from the atmosphere – which is good for the climate.
Looking to the longer term, one of the biggest advantages of building with timber is that it is obviously a naturally renewable material. A tree can be grown to a suitable harvest size in 25 to 80 years, while the raw materials for bricks, steel and plastics are only renewed over geological time – i.e finite in human terms.
Examples of timber builds
This detached 3-bedroom home and office is net zero-carbon, generates more energy than it uses, and has won two awards. Timber is used extensively throughout. The structure utilises Cross Laminated Timber (CLT), an innovative timber product with superior strength and structural durability. The exterior walls are clad with timber panels, and timber flooring is used throughout the property.
This sustainable, all-timber garden workspace has been designed for working in light and comfort with minimal heating or artificial lighting. Glazed timber sliding/folding doors and a roof-light flood the internal space with light and help with space heating. The timber frame is fabricated from Douglas Fir and the cladding from Western Red Cedar.
As one of the world's most popular building materials, there are countless examples of timber buildings. Here's just two examples of what can be achieved.
High-rise towers of glass, concrete and metal are a familiar sight in cities around the globe. Now, technical advances and materials innovation means skyscrapers can now be built with Cross Laminated Timber (see above). This one is scheduled for construction in Amsterdam in the Autumn of 2017. It will be a towering 240 feet tall.
This contemporary Scandinavian townhouse is made from CLT and glue-laminated pine, and it leaves the timber interior exposed to give the impression of the home being carved out of wood. The five-storey property is spacious, yet fits into a compact narrow plot.
— Mike England Timber (@ME_Timber) December 3, 2016
What's your favourite use for timber? And what other natural materials do you want us to cover? Tweet us your ideas at @KoruArchitects using the #SuperNaturalMaterials hashtag.