Extreme recreation

Materials World magazine
1 Aug 2017

Peter Wilson looks at the use of wood in some of the most hostile environments. 

The world’s most challenging environments are increasingly regarded as attractive opportunities for recreational activities, now fashionably termed as ‘hard adventure tourism’ by intrepid adventurers, explorers and mountaineers. In the past, the extreme physical challenges presented by these often remote locations made extraordinary demands on the capacity for humans to function at the very limits of endurance. Nowadays, however, such activity is commonplace – just as the extraordinary individual feat by Pheidippides to run the 25 miles from a battlefield near the town of Marathon to Athens in 490BC has become a mass participation phenomenon with thousands of entrants taking part in races in cities around the world. So, too, are other trials of mental and physical strength and endurance previously considered to be unique achievements now at the extreme end of recreation for many people. In international tourism, the desire to find new dangers and thrills has been commoditised and packaged for consumption – if not by the masses, then certainly by aficionados of hard adventure tourism. 

Far from accepting maximum discomfort – rock-face hardened free-climbers and experienced mountaineers out to combat ultra-difficult Himalayan ascents can, when occasion permits, be equally partial to contemporary comforts. For the more seasonal climber and skier, the provision of facilities offering these modern conveniences is a necessary part of the package – the leisurely yin to the adventurous yang. 

Retreating in the mountains 

For serious mountaineers, however, climatic conditions at great heights can often change in a moment, and the urgent need is not for leisure but for robust shelter, warmth and sustenance until the weather clears and it is possible to restart the ascent or descent. In the past, emergency requirement was met by traditional mountain huts – stone shelters, occasionally the low-to-medium altitude retreat for shepherds but, at higher levels, built to protect those exposed to the extremes of driving snow and wind chill. Alpine mountaineering attracts many more participants than ever before, with consequent additional pressures upon remote facilities – the higher the building, the greater the need for it to be fully self-sufficient – there is no possibility of connection to mains electricity or drainage. The Monte Rosa Hut, Switzerland, a design and construction collaboration between ETH Zurich and the Swiss Alpine Club (SAC) sits 2,883m above sea level and, when completed in 2009, set new standards for building in the mountains. 

Although described as a hut and formed largely from engineered wood, this is not a simple structure. It appears diminutive against the vast backdrop of the Monte Rosa Massif, several storeys high, designed by Professor Andrea Deplazes of Bearth & Deplazes Architekten and Marcel Baumgartner in Switzerland to replace a much smaller existing facility. While the SAC’s pioneering forebears saw the no-frills huts as staging points for a conquest of the Alps, its function is to protect the region, part of which is to prevent the establishment of new huts in unexplored terrain. As the organisation has proceeded to maintain and renovate the 153 huts in its portfolio, it has placed greater attention upon environmentally-friendly power supply and wastewater treatment. In the case of the Monte Rosa Hut, these issues have been ingeniously resolved within a precision-engineered timber structure that is set upon foundations designed to withstand the effects of climate change. 

Because of its large scale, the composite, prefabricated cross-laminated timber (CLT) and glulam elements were transported by helicopter to the building site – the only possible means of shifting construction materials to this very remote location minimised the number of shipments required. Weather conditions meant that the foundations were cast in summer 2008, with construction beginning in May 2009 and the building completed and opened four months later. Architecturally, its crystalline, metal-clad appearance is extraordinary, but it is the holistic approach to its design and services installation that makes it unique. Electrical power is supplied via photovoltaic technology, while thermal collectors provide the hut with melt water, stored in an underground cavern with 200m2 capacity to meet the building’s water needs. Wastewater is processed in the hut’s own treatment plant and, in the form of grey water, reused to flush toilets. The outstanding efficiency of these systems is made possible by advanced energy-management technology that ensures the quantity of energy required for its heat-energy-coupling system remains minimal. It does so by taking local weather forecasts as well as the hut’s occupancy into account and is remotely controlled from ETH in Zurich. 

Snowy hills

Elsewhere, in the Swiss canton of St Gallen, the creation of an engineered timber building on the Chäserrugg mountain presented significant design challenges for architects Herzog and de Meuron, Switzerland, as well as the specialist timber fabricator and contractor, Blumer-Lehmann AG. At an altitude of 2,262m above sea level, windspeed and snowfall can be severe. To ensure the mountaintop restaurant and ski lift terminal could withstand these pressures, a scale model of the proposed building and the surrounding landscape was tested in a wind tunnel. The problem of massive snowloads on the roof necessitated the use of large glue-laminated timber beams combined with a relatively conventional bearing structure and prefabricated timber frame elements. Interestingly, not only were the 500m2 of construction timber and 200m2 of slats transported to the site via the ski lift itself but, with the country’s long history of outstanding carpentry skills, traditional timber joints such as mortice and tenon were employed, with offsets augmented by special timber engineering connectors. The building’s heating is supplied by pellets and is delivered in 800kg sacks by cablecar rather than helicopter. The construction period embraced extremely variable weather conditions including sudden winter storms in August, severe rainfall and extreme summer heat – the completion of this facility by the assembly team in 51 weeks can be viewed as a technical triumph. 

The most recent addition to the growing catalogue of timber buildings intended to complement mountain landscapes is the Obereggen Mountain Hut, Italy, as a result of a competition-winning design by the Italian-based Pichler Architecture and Pavol Mikolajcak. This restaurant sits at an altitude of 2,096m above sea level on a small mound immediately adjacent to the Oberholz Cable Station serving the Obereggen Ski Resort that lies at the South Tyrolean Dolomites’ UNESCO World Nature Heritage Site in the northern Italian Alps. The cantilevering structure that appears to grow out of the hill resembles a fallen tree – an effect the architects describe as ‘creating a symbiosis with the landscape’ with its main branch trio terminating in glass-fronted gables facing towards the three predominant mountains to the northwest. At its other end, the main body of the building is embedded into the hillside with just the roof peeking above the surface. As it extends outwards, the roof splits into the three curved forms that are seen from below. On one side, the curve of the building embraces a south-facing terrace set on the edge of the mountain, with the exterior walls and pitched roof formed from blackened larch cladding. Inside the main restaurant area, the spruce structure is exposed, with two curvilinear supporting spines appearing to extend down from the roof to provide partitions between the three dining areas. The building’s timber structure is seen to be composed of a series of portal frames that follow the curves of the plan and taper into the walls to separate the benches and define the table positions. This is an exemplary use of modern engineered timber products – the material is in keeping with the construction traditions of the area while, in its exposed form, emphasises the hut’s sustainability credentials.  

The relationship to the immediate setting and the wider landscape has been paramount in the designers’ thinking. Architecture in these locations, no matter how large and striking in appearance, can ever hope to compete with the drama of the mountain setting it is surrounded by. There is a genuine concern and desire to care for what are considered fragile environments to ensure that these manmade interventions not only respect and offer protection to these natural attractions but also provide autonomous, modern facilities that use technologically-advanced, energy-efficient and sustainable material. The ability to employ these at high altitude brings another, vastly more complicated dimension to the construction of such facilities – one might even call it ‘hard adventure architecture.’  

Peter Wilson is an Architect and Managing Director of Timber Design Initiatives Ltd, UK. The company facilitates European approaches to continuing professional education for architects, engineers and other construction professionals in the design, manufacture and use of advanced timber technologies, supporting innovation in, and demonstration of, new timber products and systems.