TOPICS n°14 – Technology

DCF 1.0 The development of structural wood

Sonia Maritan

Wood has become a structural material with equal dignity as every other material, but with all the advantages due to its specificity. A wood construction is able to reach exceptional performances as far as energy saving, sustainability, anti-seismic safety and economic competitiveness are concerned. In fact, wood constructions can grant such timings and results that place this kind of solution even above all other construction materials. More than the structural and formal points of view, a wooden casing conveys wellness, since this material distinguishes itself for its low thermal conductivity, high thermal inertia and considerable hygroscopicity: all these characteristics enable the creation of a positive effect on air quality within a building.

Therefore, modern technology converses osmotically with the both ancient and future resourcefulness of this extraordinary substance, which nowadays is more relevant than ever considering the constantly increasing trend, together with a strongly engineered technology, which allows for the creation of always higher buildings, also thanks to the technology of machining centers which continuously assimilate working process which were exclusively handcrafted. Technology communicates with software and, thanks to the adoption of BIM methodology in the building sector as well, it completely innovates its way of conceiving projects and planning from their very basis, letting prototype and realization coincide, even anticipating the behavior if a specific building in its geological context. The modern technology of frame houses or CLT panels, usually called X-lam, as well as traditional massive wood, is opening new challenges for wood architecture in every field, for every actor in the production chain: producers, installers, builders, contractors, planners, engineers, field experts and final users. This involves also the producers of painting plants, because the finishing of the visible material presumes a better esthetic and functional performance.

According to a study realized by the study center Federlegno Arredo Eventi commissioned by Assolegno and published on 11th July, one house on 14 is made of wood, more than 3.400 new wooden houses were built in 2015, that is 7% of the total building licenses and 696 million euro the value of the realized wooden constructions, both residential and non-residential. The elaboration of the data considered for the study involved 248 producers of buildings with wooden load-wearing structure in Italy, the most diffused construction technique, the geographical distribution of the companies and their volume sales, the houses realized for the region, the estimate of the national market, the comparison between building industry in Italy and the production of wooden pre-fabricated buildings in other European countries. The results show a trend definitely opposite to the still suffering building sector (in 2015, investments in new residential buildings decreased of -6,8% if compared to the previous year) and they confirm the interest of final users for this kind of construction. Such trend does not seem to halt, as demonstrated by Italy’s fourth place among European producers of wooden buildings, with an increase rate higher than the average values. All this happened in 2015, a year which represented a transition period for wooden construction industry in a still decreasing property market, while structural wood hold the production levels reached in 2014.

On a regional level, the companies of Trentino Alto Adige play a significant role as far as generated volume sales are concerned (46% of the total), while Lombardia had the highest number of companies durably active in the sector (51 companies, that is 21%). Concerning the houses geographical distribution, Lombardia reached the first place with 20% of the realized construction, followed by Veneto (18%) and Emilia Romagna (15%). Finally, the report contains an interesting parallel study on finishing as well, where it can be seen that PVC and tiles are the most diffused materials in wooden construction for windows and floors respectively. And not only in Italy: as it can be seen from the results, the made in Italy wooden houses are more and more appreciated also abroad. Indeed, export overcame the import level for the first time.