Take a seat - Royal college of Art students' chair design

Wood Focus magazine
17 Dec 2012

A dozen budding designers, one strict brief and a large pile of wood. Melanie Rutherford follows the adventures of 12 American hardwood chairs… 

The brief - To design a seat for function. This could be a chair, stool,
bench or anything else that can be sat upon. Materials to be used are
American hardwoods and veneers.

In July 2012, 12 product design students from the Royal College of Art (RCA) spent a week in rural Berkshire, sleeping under the stars in Benchmark furniture maker Sean Sutcliffe’s back garden between intense 18-hour days crafting timber masterpieces in a design workshop. The result? Twelve wooden seats, all with varying degrees of sustainability. The students embarked on their woodland adventure through a collaborative project devised by the RCA and the American Hardwood Export Council (AHEC), for an exhibition at London’s Victoria and Albert Museum as part of September’s London Design Festival. 

Not just another college design project, the idea was to explore the potential for solid hardwood as a serious material for furniture, as well as examining its environmental impact. Life cycle analysis (LCA) technology, examining the environmental inputs and impacts throughout the life of a product, is a relatively new tool for the timber industry. PE International, a company specialising in this field, helped the students to consider their product’s sustainability. 

It is hoped that through the project, the timber industry will realise the importance of understanding the impact of a material’s lifecycle. ‘We’re trying to go back to the [concept] of sustainability, which has been tarnished and become misused in some ways,’ says AHEC’s David Venables. Some of the students’ designs were influenced by data from prior analysis of the materials, which, says Venables, can be used throughout the design process. ‘We believe designers and manufacturers are going to have to work this way in the future,’ he says. ‘We makers need designers to push us out of our comfort zones.’  

David Venables of the American Hardwood Export Council (AHEC) talks to Melanie Rutherford about the use of hardwood as a sustainable material in furniture design. 

The challenge of designing with wood is that, unlike steel or plastic, it is not one homogenous material. No two pieces of wood are identical, even within the same species. Add to this the huge availability of so many commercial species and designers are spoilt for choice, but they must be prepared to work with what nature provides. Length and width can be limited and colour variations abound. If you want every piece of furniture in a range to look identical then don’t use wood, but if uniqueness, warmth, and that tactile touch are sought, there is no substitution for real wood. 

But it’s not just about the look. Wood is easy to shape and work with to satisfy the most creative mind and its environmental credentials are the envy of other industries. It is renewable, low impact to process and not only do forests absorb carbon, but it is stored within the wood for the life of the product. 

The US hardwood forest is one of the most diverse temperate resources in the world. AHEC promotes more than 20 commercial species, some of which are similar to those found in European forests (such as white oak and ash), but where and how they grow makes them different – species such as tulipwood, sap gum and hickory, for instance, are indigenous to the USA. For sought-after timber such as walnut and cherry, the USA offers much greater commercial volumes than those found in Europe. With this great variety comes a wealth of valuable working properties. Many species are very strong for their weight, some have natural durability, for example oak, and others such as tulipwood can be easily treated. Most finish and glue well, but some require more care than others to get the best results. It is vital that furniture designers are aware of these properties, which projects such as Out of the Woods help promote. 

From a forest sustainability and environmental life cycle perspective, there is little to separate any of the main American hardwood species. US hardwoods come from mixed natural forests with a high diversity of timber types. The US Federal Forest Service has carried out detailed forest assessments every 10 years for the last century, which show that growth is significantly higher than harvest across all these types. It’s important that furniture designers experiment with a wide range of species and grades to avoid reliance on one component of this diverse natural resource. 

However, particular benefits from a resource efficiency perspective come from encouraging greater use of those species that are abundant in the forest but relatively under-used – such as tulipwood, maple, ash and hickory. Also, strong technical performance tends to go hand-in-hand with strong environmental performance. If a product works well and is durable, there is less need for replacement and there is also less waste. Another key point from a life cycle perspective is to make sure that the correct species is chosen for the job in hand. 

Although I am not really allowed a favourite, I do get a thrill from challenging perceptions and fighting for the underdog, which is why I spend so much time trying to convince markets that red oak is just as good as white oak. Why don’t we use a lot more of it when it represents more than 20% of the whole US hardwood resource and looks so appealing? Equally, why should tulipwood just be a cheap hardwood for painting, staining and moulding, when it has a higher strength-toweight ratio than any other hardwood and a dramatic marbled appearance that only nature could produce? 

Designs for life 
The students had access to 12 species of American hardwood from which to create a single piece of environmentally friendly hardwood seating. When Sam Weller crafted his Snelson Stool, he experimented with a variety of American hardwoods before deciding on a contrasting walnut seat with ash legs. 

‘One of the stools I tried to manufacture in the American white oak proved to have breakout issues when routing some components cross grain (a fairly typical issue). The advantage of using walnut for the legs was that it was very easy to work with using the simple router jigs I had fashioned. Under tension, the walnut and ash were sufficiently stiff to cope with the stress created by the tensegrity structure. 

‘I aimed to use relatively simple methods of making the components for my chair, using an inverted router to create the round on the legs, rather than turning them. Again, the circular seat was cut with a simple hand router and circular template jig.’ With the aim of assembling a seemingly complex array of parts into a simple stool design, Weller’s use of hand-based power tools ensured a low environmental impact as well as ease of production. 

Lauren Davies’ Leftovers Chair blends traditional and modern. Based on the classic Windsor design, the culinary-inspired chair is made from a variety of fruit- and nut-bearing American hardwood species akin to a list of ingredients – an idea Davies cooked up through her interest in food. Hickory was used for the legs, a species noted for its strength and straightness, which were joined to the supporting H-structure by its sister timber, pecan. ‘The components for the chair were mainly hand-shaped using a lathe, handmade jigs for steam bending, and various handheld tools,’ she explains. ‘The different species making up the seat were cut on a CNC machine. After each component was finished, I treated my chair like a meal. I found wood treatment techniques such as pickling and smoking, used fruit and spice dyes to colour the wood, and used olive oil to finish the steamed cherry bow back.’ 

Ash you like it 
Hardwoods are noted not just for their aesthetic qualities, but for their strength and hardwearing properties – take Santi Guerrero Font’s design. He opted to work with American ash, one of the strongest timbers, for his simple Num. 4 Chair. The first-year student wanted ‘to create something visually very simple and honest, and to hide the complexity of the issues involved’. The main challenge lay in making reusable jigs that could create simplelooking but difficult glued joints, which allowed the legs of the chair to pass through the structure and flush with the seat. His choice of ash, which is noted for its good response to glue, was key to achieving this. 

Ash was also the material of choice for Petter Thorne, for whom the project ‘has been about pushing the material to the limit’. The Swedishborn student’s 3.5 metre long Beeeench (sic) design’s only support comes from the two legs at either end. Its strength owes to Thorne’s clever construction of the long, thin slats, measuring just 5mm thick, into a three-dimensional arrangement. ‘Ash’s properties allowed such an extreme construction,’ he adds, nodding to the flexible nature of the wood, which allowed the seat enough give for it to bear the weight of the user. 

For hardwood chairs destined for indoor use, the raw material is normally artificially dried in kilns to speed up the process. With sustainability at the forefront of the students’ minds, removing this step was a useful way to reduce the environmental impact of their designs. Such was the case for Anton Alvarez, whose outdoor Tree Furniture comprises a single log, carved in situ. 

‘To sculpt the wood I used a portable saw mill, which consists of a big chainsaw that runs along two aluminium tracks attached to the log,’ he explains. Alvarez’s choice of hardwood species owed, in part, to this carving process. Of all the hardwood species, cherry is renowned for being easy to machine and fix, the medium density grain offering a smooth finish when sanded. ‘The material has a good a technical character for outdoor use, even though it is an exclusive type of wood [normally used for indoor furniture],’ he says. ‘American cherry has a very interesting visual character. I like its pink colour and anonymous grains, and its ability, in contrast to many other types of wood, to darken in sunlight over time.’ 

A chair is for life 
Just as many lessons were learned on this multi-faceted project, many questions arose. What is more important to the customer – form, function, environmental impact or commercial viability? If hardwood is indeed a feasible choice for largescale production, will customers be willing to pay the price for such a quality, sustainable product? Venables believes so. ‘As environmental considerations have more impact on what we buy, wood and its positive lifecycle will undoubtedly play a more prominent role in product design and architecture.’