The authors on the basis of practical experience have analyzed low-rise construction with the use of energy-saving technologies. Characteristic features of possible variants of frame construction are looked at and described. The relevance of the paper consists in the improvement of the building frame design solution based on the analysis and elimination of disadvantages taking into account consumers' point of view.

A variety of climate mitigation strategies is available to mitigate climate impacts of buildings. Several studies evaluating the effectiveness of these strategies have been performed at the building stock level, but do not consider the technological change in building material manufacturing. The objective of this study is to evaluate the climate mitigation effects of increasing the use of biobased materials in the construction of new residential dwellings in Sweden under future scenarios related to technological change. A model to estimate the climate impact from Swedish new dwellings has been proposed combining official statistics and life cycle assessment data of seven different dwelling typologies. Eight future scenarios for increased use of harvested wood products are explored under different pathways for changes in the market share of typologies and in energy generation. The results show that an increased use of harvested wood products results in lower climate impacts in all scenarios evaluated, but reductions decrease if the use of low-impact concrete expands more rapidly or under optimistic energy scenarios. Results are highly sensitive to the choice of climate impact metric. The Swedish construction sector can only reach maximum climate change mitigation scenarios if the low-impact building typologies are implemented together and rapidly.

This paper investigates ways in which weathering-related site conditions can be allowed to inform the design process in order to improve a building's geometry and performance. Providing a building design with the capacity to remember past experiences and anticipate future events can provide substantial gains to the architectural configuration and engineering of a timber façade. A new theory of architecture is outlined based on recent “teleodynamic” theories—a hypothesis about the way far-from-equilibrium systems interact and combine to produce emergent patterns. The proposed explanation considers nested levels of thermodynamic systems applied to an architectural context: “homeodynamic” operations that involve equilibration and dissipation of constraint combine to produce self-organising “morphodynamic” procedures that amplify and regularise site-specific constraining data streams. A teleodynamic design reconstitutes itself by combining morphodynamic processes so as to optimise its relationship to the past, present, and future. A novel teleodynamic design tool called Contextual Optimisation Workspace (COW) is assembled within the Grasshopper visual programming environment. The tool is used to carry out four experiments that combine to produce the teleodynamic design of an urban wooden façade, exemplifying an alternative framework for the design of wood-based structures. The first experiment investigates a variegated grid combining two distinct subdivision methods (an orthogonal grid and a Voronoi tessellation), transmuting one system into another. The second and third experiments focus on durability aspects of a wooden façade and devise strategies for how the effects of photochemical degradation and wetting due to driving rain might be minimised using the COW tool. The fourth experiment optimises the building for daylight based on an illuminance simulation. Using simulation and anticipation to add the advantages of site- and time-specific data streams as a design strategy can effectively suspend an algorithm-driven design iteration in time and space in order to allow it to be parametrically influenced by past or future events such as unique site and project conditions. The COW tool can be used to produce such teleodynamic designs.

Whenever Life Cycle Assessment (LCA) is used to assess the climate impact of buildings, those with high content of biobased materials result with the lowest impact. Traditional approaches to LCA fail to capture aspects such as biogenic carbon exchanges, their timing and the effects from carbon storage. This paper explores a prospective increase of biobased materials in Swedish buildings, using traditional and dynamic LCA to assess the climate impact effects of this increase. Three alternative designs are analysed; one without biobased material content, a CLT building and an alternative timber design with “increased bio”. Different scenario setups explore the sensitivity to key assumptions such as the building's service life, end-of-life scenario, setting of forest sequestration before (growth) or after (regrowth) harvesting and time horizon of the dynamic LCA. Results show that increasing the biobased material content in a building reduces its climate impact when biogenic sequestration and emissions are accounted for using traditional or dynamic LCA in all the scenarios explored. The extent of these reductions is significantly sensitive to the end-of-life scenario assumed, the timing of the forest growth or regrowth and the time horizon of the integrated global warming impact in a dynamic LCA. A time horizon longer than one hundred years is necessary if biogenic flows from forest carbon sequestration and the building's life cycle are accounted for. Further climate impact reductions can be obtained by keeping the biogenic carbon dioxide stored after end-of-life or by extending the building's service life, but the time horizon and impact allocation among different life cycles must be properly addressed.

This paper will present a study of preconditions for competitiveness in a resource saving society. Preconditions for material suppliers and industry versus requirements from legislation and consumers means a balance, which can be difficult to manage. The paper is aiming for an analysis of the preconditions for property modification, innovation and marketing of biobased materials and products, and the paper deals with strategies to release the architectural potential of bio-based construction. 

Cross Laminated Timber uses the anisotropy of wood to its advantage by placing laminations across the grain. This elegant solution has led to Cross Laminated Timber (CLT or XLAM) being among the most significant recent innovations in timber engineering. It has grown to an economically significant area of R&D in wood sciences and has the ability to replace many traditional building products with a sustainable solution capable to answer the requests of our contemporary society, e.g. regional production, innovative and flexible designing possibilities, sustainability as well as safe design with respect to the building process and the final product.

Invented in Mid Europe some decades ago, the most influential research and development of this product has also been based in Europe for a long time. This is challenged today, as other continents – having started work in this field later but as one joint effort – tend to overtake the European success story. The reasons for this are the known challenges within a unified Europe, very long standardization processes necessitating individual national approaches as well as competition within the timber construction sector rather than joint approaching of new markets.

This conference has compiled knowledge about the material and its use, focusing on the design of CLT structures in ambient and fire situations. To this aim, two COST Actions – FP1402 Basis of structural timber design – from research to standards, and FP1404 Fire Safe Use of Bio-Based Building Products – joined efforts to provide contributions and presentations from world leading experts and to bring together expert communities to realize a scientific discourse on these important and interdisciplinary topics, leading to further joint harmonisation progression in research and development.

This Joint Conference was meant to contribute to a high-quality and open scientific and technical dialogue within the timber community. The programme therefore included time for debate after the presentations as well as the formation of Think Tanks in which all participants, guided by essential questions, discussed the future challenges and development of CLT.

During the Joint Conference, over 200 participants from the worldwide CLT community (ca. 50% coming from industry) showed their will to initiate joint work, concentrating strengths with respect to simplification, harmonisation and, most of all, understanding different points of views. This book contains not only the State-of-the-Art in research and practice, it also documents the valuable thoughts of experts on challenges and necessary developments of CLT within the next years.

The first modern applications of massive ti mber plate element s wer e seen in bridge decks in Canada and the US in the 1970's. Two decades l ater the concept was tak en as point of departure for ex tensive research on primarily residenti al building c onstruction a nd bridge decks in Central Europe in the e arly 1990's. Today the range of applic ations has be en widened to include an increasing share of applications in non-residential buildings as well as in geometrically far more complex structures. Thereby the requirements on joint properties, stability and detailing etcetera-i.e. the problem issues-have changed, increasing the demands on innovation and solutions both in research and practice. Thus, issues to research and innovate developed applications and multi-objective approaches have succeeded first basic resear ch efforts. This paper describes this development and defines current needs and proposes topics for further studies for the next generation of structural systems based on cross-laminated timber, CLT.

The first modern applications of massive timber plate elements were seen in bridge decks in Canada and the US in the 1970's. Two decades later the concept was taken as point of departure for extensive research on primarily residential building construction and bridge decks in Central Europe in the early 1990's. Today the range of applications has been widened to include an increasing share of applications in non-residential buildings as well as in geometrically far more complex structures. Thereby the requirements on joint properties, stability and detailing etcetera - i.e. the problem issues - have changed, increasing the demands on innovation and solutions both in research and practice. Thus, issues to research and innovate developed applications and multi-objective approaches have succeeded first basic research efforts. This paper describes this development and defines current needs and proposes topics for further studies for the next generation of structural systems based on cross-laminated timber, CLT.

Different methods using evolutionary computation (EC) have been successfully applied to structural form optimization for many years. A well known limitation of these methods is the computational effort required to analyze significantly large and complex systems. As a result most examples have been limited to simple truss forms or smaller aspects of overall structural systems. This is because the number of variables used to describe the structural geometry limits the size and complexity of problems that can be explored using EC methods. One solution to this limitation is the use of associative parametric models. In recent years use of parametric modeling software has become more widespread in architectural design. Parametric approaches to geometric modeling have the advantage that they are able to describe large, complex systems with very few variables. The reduced number of variables needed to describe geometric systems makes parametric models ideal for use with EC to explore optimal forms. This paper shows examples of how large, complex structural systems can be optimized for basic parameters like weight and number of components by combining a genetic algorithm with a finite element analysis and parametric modeling software. The procedure is outlined with specific applications. Examples show the use of this technique used to explore complex spatial structures. Results are shown with specific documentation of computational effort required.