Developments in Tall Wood and Hybrid Buildings and Environmental Impacts

Wood has been gaining popularity as a building material over the last few decades. There has been significant progress in technology during this period to push the limits of wood construction. At the same time, it has become more economically competitive to build with wood beyond low-rises. As a result, there has been a noteworthy shift in public perception in terms of acceptance of wood as a material for high-rise buildings. There is a growing list of tall wood buildings that have been constructed in different continents over the last decade. With worldwide population growth and increased urbanization, the trend is expected to continue. Considerable urgency for using sustainable resources to tackle the threat of climate change has resulted in a surge in demand as well as applications in recent decades. This paper reviews the significant technical advances that have contributed to those achievements and are expected to facilitate further developments.

Examining the magnitude and perception of summertime overheating in London care homes

This paper brings together objective and subjective data on indoor temperature and thermal comfort to examine the magnitude and perception of summertime overheating in two London-based care homes occupying modern and older buildings. Continuous monitoring of indoor and outdoor temperature, relative humidity and CO2 levels was conducted in summer 2019 along with thermal comfort surveys and semi-structured interviews with older residents and staff of the care settings. Indoor temperatures were found to be high (>30°C) with bedroom temperatures often higher at night than daytime across both care settings. Limited opening due to window restrictors constrained night-time ventilation. Overheating was prevalent with four out of the five monitored bedrooms failing all four overheating metrics investigated. While 35–42% of staff responses perceived indoor temperatures to be uncomfortably hot, only 13–19% of resident responses were found to do so, indicating that elderly residents tend to be relatively insensitive to heat, leaving them open to overheating without realising it. Residents and staff in the modern care setting were less satisfied with their thermal conditions. As hybrid buildings, care settings need to keep both residents and staff comfortable and healthy during hot weather through night-time ventilation, management of heating and supportive institutional practices. Practical application: Care home designs have focused on keeping residents warm through the winter, neglecting the risks of summertime overheating. Care homes are hybrid buildings serving as living spaces for vulnerable older residents and offices/workspaces for staff. Providing comfort to both groups during periods of hot weather is challenging. Opportunities for ventilation are limited by Health & Safety regulations that mandate up to 10 cm maximum window openings and institutional practices that result in windows routinely kept closed, particularly at night. Utilising natural and where possible cross-ventilation should be considered along with external shading. Heating should be managed to avoid unwanted heat gains in the summer.

A State of the Art of the Overall Energy Efficiency of Wood Buildings—An Overview and Future Possibilities

The main goal of this study was to review current studies on the state of the art of wood constructions with a particular focus on energy efficiency, which could serve as a valuable source of information for both industry and scholars. This review begins with an overview of the role of materials in wood buildings to improve energy performance, covering structural and insulation materials that have already been successfully used in the market for general applications over the years. Subsequently, studies of different wood building systems (i.e., wood-frame, post-and-beam, mass timber and hybrid constructions) and energy efficiency are discussed. This is followed by a brief introduction to strategies to increase the energy efficiency of constructions. Finally, remarks and future research opportunities for wood buildings are highlighted. Some general recommendations for developing more energy-efficient wood buildings are identified in the literature and discussed. There is a lack of emerging construction concepts for wood-frame and post-and-beam buildings and a lack of design codes and specifications for mass timber and hybrid buildings. From the perspective of the potential environmental benefits of these systems as a whole, and their effects on energy efficiency and embodied energy in constructions, there are barriers that need to be considered in the future.

Amplification Factor for Wood-Concrete Hybrid Structures Based on Dynamic Numerical Simulation

Extensive concerns on environmental protection have provoked low-carbon buildings to be the mainstream of building construction worldwide, and wooden structures in this sense outperform other structural forms. Wooden-concrete hybrid structures featuring distinct wooden and concrete stories typically exhibit uneven stiffness distribution along the structure height; in particular, abrupt stiffness changes occur at the wood-concrete transition stories. Therefore, structural designing of such hybrid structures must consider a stiffness amplification effect in the static structural calculation as well as complicated procedures in the dynamic analysis. To determine an appropriate amplification factor for design purpose, this study employed a dynamic numerical approach to determine the displacement response of wooden-concrete hybrid buildings and compared the results with the displacement response obtained from static analyses. According to the results, it is found that the appropriate amplification factor should beα= f (x) = 0.47x + 1.00.αcan be valued 1.94 at 2nd floor, 2.41 at 3rd floor and 2.88 at 4th floor. The results may serve as a reference for seismic designing of wooden-concrete hybrid structures.

Evolution of the Building-Machine Hybrid on the Example of Historical Oast Houses

Hybrid buildings are not a modern invention. In the case of certain types of buildings in historical production facilities, a degree of inseparable fusion of static buildings and dynamic mechanics can be detected. This goes far beyond the multifunctional use of a room and also includes constructional and architectural design to the same extent. They are not simply rooms or buildings in which machines for the production of an item or a product are installed, but the room, or the building, itself, is the “machine”, or at least an essential part of it. Or is the machine the building? This relationship will be explained using the example of historical oast houses. For this type of building, architectural development from an integrated yet barely perceptible component to a free-standing solitary building can be demonstrated over a period of around 80 years. It is not clear which part is the building and which is the production technology. These two main components have become an indissoluble unit, making the oast house a real hybrid.Zusammenfassung Hybride Gebäude sind keine Erfindung der Neuzeit. Bei bestimmten Bautypen historischer Produktionsstätten ist eine Größenordnung der Durchdringung von statischem Gebäude und dynamischer Mechanik festzustellen, die nicht aufzulösen ist. Dies geht weit über die multifunktionale Nutzung eines Raumes hinaus, und umfasst in gleichem Maße auch die Konstruktion und architektonische Gestaltung. Es sind keine Räume, oder Gebäude in denen Maschinen zur Produktion eines Gegenstandes oder einer Ware aufgestellt werden, sondern der Raum, oder das Gebäude selbst ist die „Maschine“, oder zumindest ein wesentlicher Teil von dieser. Oder ist die Maschine das Gebäude? Am Beispiel historischer Darren soll dieser Zusammenhang erläutert werden. Für diesen Gebäudetyp kann in einem Zeitraum von etwa 80 Jahren eine architektonische Entwicklung vom visuell kaum wahrnehmbaren und integrierten Bauteil zum freistehenden Solitär nachgewiesen werden. Dabei ist nicht eindeutig festzustellen, welcher Teil das Gebäude ist, und welcher die Produktionstechnik. Aus den beiden Hauptkomponenten ist eine unauflösbare Einheit geworden, womit die Darre zum echten Hybrid wird.