Studies have shown that 70% of timber and wood products are being used in the construction industry, with the real estate sector, interiors, furniture and other industrial applications following closely behind. Organisers of the Dubai Wood Show, held earlier this year, believe that the overall construction activities, valued at US$2.4tn in the GCC region, is driving the demand for wood products.
According to a recent report, the world’s biggest joineries are based in the Middle East, making the region ripe for wood-origin products for surface design.
Roderick Wiles, director – Africa, Middle East, South Asia, Oceania, American Hardwood Export Council (AHEC), tells Commercial Interior Design how American hardwood varieties are being applied to interior surfaces.
For which commercial applications is American hardwood the most suitable choice, and why?
In the Middle East, American hardwoods are well-established as a preferred material for interior projects and furniture, due to the wide range of species, their performance, aesthetic appeal and excellent environmental credentials. American hardwoods are extremely well-suited to a very wide range of interior applications, be they in private residences, large public buildings, commercial offices or retail spaces. Furniture, flooring, doors and joinery are all ideal end uses for these hardwood species, while in certain limited applications, they can also be used outside or even structurally. In the harsh climate of the GCC, however, we would hesitate to recommend using any of the American species externally unless they had undergone some sort of treatment or modification for exterior use.
Can American timber be modified for specific purposes? If so, how?
The wide range of American hardwood species offer architects and designers a wonderful palette of colours, textures and grains to use for furniture and in interiors. What they do not offer, however, is a very durable wood species that can be considered for outdoor applications such as cladding or decking.
Meanwhile, their use in structural applications has been somewhat limited by a lack of know-how. However, this is now changing through the application of new, and relatively simple technology coupled with a readiness to consider it as a material for a wider range of construction solutions.
With an aim to develop new markets for American hardwoods, AHEC realised early on that wood modification was going to play a very significant role. Applying thermal modification process to wood enables a non-durable species to be used externally. The modern commercial method of thermal modification that we know today was developed in Scandinavia 30 years ago, enabling the plentiful local softwood resource to be made durable without the application of chemicals. Certain temperate American hardwood species also lend themselves well to the thermal modification process. The leading species are ash, tulipwood, soft maple, yellow birch and red oak. Some lesser-known species such as hackberry, sapgum and basswood can also be used.
AHEC has used thermally-modified timber (TMT) to showcase its potential for outdoor application in a number of their design collaborations. The first project was the Infinity Bench by designer Martino Gamper for the 2012 London Design Festival. In his unique design, he used five different TMT American hardwood species; tulipwood, ash, soft maple, red oak and yellow birch. The range allowed for an exciting contrast in colours, grains and textures, reflecting on their versatality.
Other bench design collaborations in thermally-modified American hardwoods include Emirati designer Khalid Shafar’s City’s Bench in Dubai. An interesting project also using TMT was ‘The Cocoon’, a collaborative installation between Dubai-based T.ZED Architects and AHEC, which was initially designed for Downtown Design Dubai 2016 and is now serving as an observation deck at the Dubai Creek Harbour Promenade.
Cross-laminated timber is quickly becoming established as an important construction material. Made from low-cost softwood, it is essentially a thicker version of plywood that is ideal for making structural wall panels and floor cassettes.
At the 2013 London Design Festival, AHEC set out to show that American hardwoods could also be considered as the raw material for structural cross-laminated timber (CLT). The result was the innovative Endless Stair, designed by Alex de Rijke of dRMM. This complex, free-standing structure explored the first use of hardwood CLT, using American tulipwood in this Escher-inspired series of staircases. While in situ, the Endless Stair allowed for many fine views over London and the Thames from its location outside the Tate Modern Gallery.
Building on this experience, dRMM designed the world’s first building made from hardwood CLT in the UK. Supported by AHEC, the opening of Maggie’s Oldham was a pivotal moment for modern architecture and construction. dRMM chose tulipwood for the design of Maggie’s Oldham for the positive influence wood has on people and for the beauty, strength and warmth inherent to American tulipwood.
The project has been constructed from more than 20 panels of five-layer cross-laminated American tulipwood, ranging in size from 0.5-12m long, which were developed by CLT specialists – Züblin Timber. For AHEC, Maggie’s Oldham is one of the most important developments in a decade of research and development into structural timber innovation and one that could broaden the use of CLT in the construction industry.
Tulipwood is particularly useful in structural applications given its very high strength to weight ratio. In fact, American tulipwood CLT is around three times stronger and stiffer in ‘rolling shear’ than its softwood equivalent and its potential in wood construction is extremely promising.
Through AHEC’s vision, sustainable American hardwoods are now beginning to enter new and exciting commercial markets. As the world re-embraces timber as a building material, it is hoped that they will become recognised more for the possibilities they can offer in all aspects of design and construction.
What are the sustainable benefits of using American hardwood?
Specifiers often question whether or not wood can be considered to be a sound choice on environmental grounds. In fact, provided it derives from a sustainably managed forest, timber is, arguably, the most environmentally-friendly material available.
In the case of American hardwoods, it has a very low (often negative) carbon footprint, it is abundant and renewable. Its harvesting and processing do not use or produce harmful chemicals or by-products and it has low embodied energy. The same cannot be said for almost any other material, even factoring in transport to the Middle East.
American hardwoods have many strong technical qualities, often out-performing competing materials. Given its high strength to weight ratio, lightweight timber members can provide the same structural strength as much heavier alternatives.
Wood also has very low thermal conductivity compared to many other building materials. This means that it can act as a superior barrier to both heat and cold, resulting in both lower insulation and energy requirements for a building, which translates into lower carbon emissions and lower running costs.
In addition, it has excellent acoustic properties and it can also provide health benefits over, say, alternative flooring materials, such as carpets.