The world's population is moving to cities at an accelerating pace. This means that soon, around the world, new homes, business properties, and offices need to be built.The solution may lie in wood construction.
Wood is a fossil-free alternative. It absorbs carbon throughout its life cycle, and wood structures can store carbon for up to centuries.
According to a study published by Yale School of the Environment and the Potsdam Institute for Climate Impact Research in January 2020, an annual amount of about 10 to 68 million tonnes of carbon can be sequestered globally by increasing urban wood construction.
This would also reduce the carbon dioxide emissions from construction.
Industrial components create new opportunities
Urban wood construction requires the reformation of building technologies, as well as the ability to adapt to operations in densely built environments.
Engineered wood products – that is, construction components made from wood – have developed enormously over the past 50 years.
These include glulam, which became popular in construction in the 1950s, as well as laminated veneer lumber (LVL), which was introduced in construction in the 70s, and cross-laminated timber (CLT), which was developed for industrial production in the mid-90s. In addition, the window and door industries use finger-jointed timber.
New methods enable construction component manufacturers to break down wood materials down into small parts and reassemble them for the intended purpose of use. This enables equipping the components with the desired features while also eliminating vulnerabilities and weaknesses
Glulam, CLT and LVL allow for longer spans in construction. Thanks to their easy jointing techniques, airtightness, frame bracing and minimal deflection, CLT and LVL are also competitive in wooden high-rises.
Prefabrication accelerates construction
New high-rises are built from elements processed in factories. Large elements are ready walls with doors and windows. Modular units are box-like structures with factory-installed surface materials, skirting, fixtures, appliances and building technology.
This enables large-scale wood construction.
Political decisions are also a strong driver of wood construction. Regulations to promote the use of wood have been implemented in France, among other countries. Green construction is supported through city and town plans.
The major change will happen when the low-carbon approach and the reduction of emissions are included in building regulations.
Builders will have to use calculations to show where the raw materials come from, how much energy their manufacture and transport consume and how much emissions they generate. At that point, wood will have the upper hand.
Examples of new wood architecture
Brumunddal, Norway: Mjøstårnet
This wooden high-rise became the world's largest wooden building upon its completion in March 2019. With 18 storeys, it is 85.4 metres tall. The building houses apartments, a hotel and offices. Wood products from local manufacturers were used in its construction.
Seville, Spain: Metropol Parasol
Consisting of 3,400 wooden elements, Metropol Parasol is one of the world's largest wooden constructions. It is 150 metres long and 75 metres wide. This wooden building was opened to the public in 2011. LVL panels were used in its construction, and computer modelling in its design and construction
Vienna, Austria: HoHo Wien
HoHo Wien is one of the world's largest wooden apartment buildings. The building is 84 metres high, with 24 storeys. In addition to apartments, the building has offices, a hotel and other facilities. From the ground floor upwards, around 75 per cent of the building is wood.
This article was originally published in Timber Magazine issue 2020–2021. Read the whole article.