“Das Thema Holz befindet sich aufgrund seiner natürlichen Beschaffenheit an der Schnittstelle zwischen akademischen, industriellen und politischen Aktivitäten. Die drei Akteure müssen aufeinander abgestimmt sein, ansonsten ist jede Anstrengung vergebens”
Presentation
Juan José Ugarte, architect, is a full professor at the Universidad Catolica in Santiago and chair in design and construction in wood. For many years he was director of the CIM (Centro de Innovación en Madera) at the same university. Juan José Ugarte is also president of CORMA, the trade association of the forest sector in Chile and he is co-chair of the WCTE (World Conference on Timber Engineering), which will take place in South America for the first time in 2021.
What is, in your opinion, the most relevant information gap and/or prejudice concerning timber construction?
The prejudices regarding the wooden construction are not transversal among general public, architects, engineers, industry and public administration: each category has its own.
In the case of Chile, the architects embraced the theme of wooden construction with strength, making innovative works, doing research, promoting dissemination and knowledge. On the engineering side, interest in this topic developed later, as there was practically no demand for this professional service.
With the approach of an industry that anticipated some R&D scenarios, universities started looking for staff who had a specialization in timber construction, creating courses for the design of wooden structures and product development. Now these subjects are part of the curriculum of the new generation of students.
On the industry side, wood is seen as a material that competes with other building materials; they wait for market demand before providing new products and services.
The lack of a real demand is related to prejudices against wooden construction. The traditional wooden house in Chile is a precarious building which does not comply with the regulations of fire resistance, acoustic insulation, thermal insulation etc. In collective consciousness, the wooden house is associated with the emergency hut and not with high quality and performance standards. We have experienced it in person working on a project in Chañaral, in the north of Chile. Here 400 families lost their homes due to flooding and as CIM, together with MINVU (Ministerio de Vivienda y Urbanismo) and the industry, we proposed to rebuild the neighborhood entirely in wood. After an exhibition of all the advantages and quality standards that the wooden construction would have given, showing international case histories, the 400 families gathered stood in a frozen silence. A manager who was in the room broke this silence and rose her hand for a question: „Architect, we have already lost everything, why do you want to build us a house for the poor?“ We understood that we had to start from scratch. Together with CORFO (Corporación de Fomento), which belongs to the Ministry of Economy, and the MINVU, we built a complete three-storey house prototype to allow people a direct experience of the modern wooden house. In the end, we managed to build an eco-friendly neighborhood there with 360 wooden housing units – in the Atacama region, the driest desert in the world.
Where do you think research is needed?
At the local level there are two fundamental reasons.
The first is the development of a new seismic standard appropriate for wooden construction. Chile is a country with high seismicity and therefore we have a very elaborate regulation: a building must withstand 7 grade-7 earthquakes in 40 years. We like to say that the safest place in the world to experience an earthquake is Chile! The standard was drawn up on the basis of the design of reinforced concrete: for example, the limit of the maximum horizontal deformation is 2 per thousand (in Europe it is 5 per thousand, editor’s note): to obtain those deformations you have to stiffen the structure, using more wood and more connectors. This causes a distortion in the conception of the wooden construction and also an important surcharge; wooden construction therefore loses competitiveness in the market for „artificial“ reasons, as the seismic design criteria are based on the experience of an extremely different material such as reinforced concrete.
The second point where research is needed is the process line of industrialized construction. From literature we know the advantages of industrialized construction: the positive impacts on productivity, faster delivery times, construction quality, but our industry continues to work using a very artisan work method. Although there may be an industry that provides industrialized solutions, the material is received on site as in traditional construction. It happened to us in Chañaral: we shipped the prefabricated building elements so that they could be assembled on arrival, but the companies kept a 2-3 month warehouse. The development of a well-documented process, which highlights the advantages of the industrialized construction model across the supply chain, is a second line of research vital for the sector to aspire to have a greater impact in the local industry.
The wood agenda, by its natural vocation, is at the crossroads between academia, industrial and public policy activities. The three actors must be aligned otherwise every effort is in vain. The risk is to stick to modifying codes, or to let the industry advance in a non-innovative way, if progress is not achieved through scientific activity of international resonance. The agenda also has an important characteristic: it must be interdisciplinary by nature. It is not a matter of engineers, architects, economists, lawyers, designers, in an exclusive way; it is necessary to generate and build trust between the environments and to achieve short-, medium- and long-term cooperation objectives.
What are the most widely used solutions for large volume wooden construction? What will happen in the next future of timber construction?
The typical Chilean wooden construction concerns two-storey timber frame houses, built on the outskirts of cities, at low cost. Until 5 years ago, everything was built at the foot of the work but now, we have 4-5 industrial plants that supply prefabricated elements that facilitate this type of construction.
At CIM we developed technological solutions for timber frame buildings up to 6 storeys high. With the construction of the Torre Peñuelas (see photo), we demonstrated that the structural, thermal, acoustic and fire resistance performance with this system was possible in Chile and adequately complied with the regulations. For buildings of 7 floors and over, other technological solutions of wood engineering are used: laminated wood, LVL, CLT and mixed systems in general.
The challenge ahead is to bring wooden construction to the city center, where the cost of the land is high. Now the demand for central positions is increasing, therefore we are developing technical solutions that allow to „occupy“ these central positions with 5-6 storey wooden buildings, making them competitive with traditional systems.