http://www.mdpi.com/journal/buildings Latest open access articles published in Buildings at http://www.mdpi.com/journal/buildings http://www.mdpi.com/2075-5309/3/2/357 If, as I have argued elsewhere, architecture and archaeology share homological correspondences of common origin thus enabling analogical relationships of creative juxtaposition, then it becomes possible to characterise those correspondences through their representational drawing practices as they are embodied in the products of those practices and in the instruments which make those products. This characterisation is the subject of this paper, first by examining architecture and archaeology as disciplined suites of practices nurtured and developed within the constraints of their parent profession, and then through the examination of particular drawing techniques and instruments—techniques and instruments either common to each discipline or abandoned by them. These commonalities and abandonments reveal their undisciplinary nature. This loosening of disciplinary constraint is further examined through the analysis of “undisciplined drawing” case studies. Buildings 2013-05-15 3 2 Article 10.3390/buildings3020357 357 379 2075-5309 2013-05-15 doi: 10.3390/buildings3020357 Alessandro Zambelli http://www.mdpi.com/2075-5309/3/2/341 This paper is a study of the photovoltaic (PV) systems in the buildings’ design of the Battery Park City (BPC) residential development, in New York. The BPC development is the first in the US to mandate, through the 2000 Battery Park City Authority (BPCA) guidelines, the use of PV as a renewable energy generation system in its individual buildings. The scope of this study is to show how PV is integrated in the BPC buildings’ design process, and what can be learned for future PV applications. The study draws directly from the design decision making sources, investigating on the concerns and suggestions of the BPCA director of sustainability and the BPC architects and PV installers. It attempts to contrast a theoretical approach that sees PV as a technology to domesticate in architecture and bring, through grounded research, PV industry closer to the architectural design process. The findings of the study suggest that while stringent environmental mandates help, in the short term, to kick-start the use of PV systems in buildings, it is the recognition of the PV’s primary role as energy provider, its assimilation in the building industry, and its use in a less confining building program that allows for its evolution in architecture. Buildings 2013-04-29 3 2 Article 10.3390/buildings3020341 341 356 2075-5309 2013-04-29 doi: 10.3390/buildings3020341 Simone Medio http://www.mdpi.com/2075-5309/3/2/324 This paper discusses collage as a means to explore spatial ideas. It concerns the practice of drawing-as-research, the spatiality of drawing and the nature of paper. It questions the homogeneity of digital tools in contemporary practice. It is introduced with a discussion of architectural representation and space with a historical trajectory. It questions an understanding of space-as-geometry and discusses the potential role of non-perspectival drawings and non-digital drawing in current practice. The collage studies focus on the late nineteenth century. Working in the tradition of the collage novel, and with original engravings from the popular French newspaper Le Grande Illustré (1904), the collages work with the thematic structure and spatiality of Stéphane Mallarmé’s revolutionary poem Un Coup de Dés written a few years earlier. In this paper, the spatial and thematic content of Mallarmé’s poem are visualized for the first time. The conclusions of this study concern the role of non-digital drawings in the profession, and the potential of creative “paper technologies” to engage the material imagination at the early stages of a design process. It opens new ground as a study of the spatiality of text, the relationship between dramaturgy and architecture and on the nature of topological drawings. Buildings 2013-04-11 3 2 Article 10.3390/buildings3020324 324 340 2075-5309 2013-04-11 doi: 10.3390/buildings3020324 David Dernie http://www.mdpi.com/2075-5309/3/2/300 Manchester Civil Justice Centre is a striking contemporary 14 storey court building which has won awards for many different aspects of its design, construction and sustainability. From November 2002 to July 2005, the author was a key member of Denton Corker Marshall’s London project team having responsibility for key areas of design development, integration of technology and sustainable design including the East elevation’s “environmental veil”. This paper tracks the procurement of the building, describing its low energy features and their performance in practice. The paper reviews the low carbon elements of the design (daylight and natural ventilation systems) in the context of similar buildings and the buildings operational performance. The building has a mixed mode ventilation system which is managed centrally; the paper describes the ongoing relationship between the Facilities Management and the building’s users and their expectations of comfort and offers an explanation as to why the building’s energy performance is not as good as predicted at design stage. A case is made that this building is a significant example of low energy design and would form a good example for a detailed Post Occupancy Evaluation. The energy performance of the building could be studied in more detail to encourage the users (judges, staff and the public) to improve the building’s energy performance and to share knowledge within the construction industry. Institutional and commercial barriers to the more mainstream adoption of Post Occupancy Evaluation are discussed with respect to the Manchester Civil Justice Centre. Buildings 2013-04-11 3 2 Article 10.3390/buildings3020300 300 323 2075-5309 2013-04-11 doi: 10.3390/buildings3020300 John Napier http://www.mdpi.com/2075-5309/3/1/278 The benefits of choosing refurbishment over new build have recently been brought into focus for reducing environmental impacts of buildings. This is due to the fact that the existing buildings will comprise the majority of the total building stocks for years to come and hence will remain responsible for the majority of greenhouse gas emissions from the sector. This paper investigates the total potentials of sustainable refurbishment and conversion of the existing buildings by adopting a holistic approach to sustainability. Life Cycle Assessment (LCA) and questionnaires have been used to analyse the environmental impact savings (Co2e), improved health and well-being, and satisfaction of people living in refurbished homes. The results reported in the paper are based on a two year externally funded research project completed in January 2013. Buildings 2013-03-13 3 1 Article 10.3390/buildings3010278 278 299 2075-5309 2013-03-13 doi: 10.3390/buildings3010278 Behzad Sodagar http://www.mdpi.com/2075-5309/3/1/258 This paper presents energy and environmental performance analyses, a study of summer indoor temperatures and occupant behavior for an eight story apartment building, with the goal to combine high energy efficiency with low environmental impact, at a reasonable cost. Southern Portvakten building is built with prefabricated timber elements using passive house principles in the North European climate. Energy performance was analyzed through parametric studies, as well as monitored energy data, and complemented with analysis of occupant behavior during one year. Results show that airtight, low-energy apartment buildings can be successfully built with prefabricated timber elements in a cold climate. The monitored total energy use was 47.6 kWh/m2, excluding household electricity (revised to a normal year), which is considerably lower than of a standard building built today in Sweden—90 kWh/m2. However, the occupancy level was low during the analyzed year, which affects the energy use compared to if the building had been fully occupied. Environmental analysis shows that the future challenges lie in lowering the household and common electricity use, as well as in improving the choices of materials. More focus should also lie on improving occupant behavior and finding smart solar shading solutions for apartment buildings. Buildings 2013-03-04 3 1 Article 10.3390/buildings3010258 258 277 2075-5309 2013-03-04 doi: 10.3390/buildings3010258 Ivana Kildsgaard Anna Jarnehammar Anna Widheden Maria Wall http://www.mdpi.com/2075-5309/3/1/245 One of the most important factors when low energy houses are built is to have good heat recovery on the ventilation system. However, standard ventilation units use a considerable amount of electricity. This article discusses the consequences on a system level of using hybrid ventilation with heat recovery. The simulation program TRNSYS was used in order to investigate a ventilation system with heat recovery. The system also includes a ground source storage and waste water heat recovery system. The result of the analysis shows that the annual energy gain from ground source storage is limited. However, this is partly a consequence of the fact that the well functioning hybrid ventilation system leaves little room for improvements. The analysis shows that the hybrid ventilation system has potential to be an attractive solution for low energy buildings with a very low need for electrical energy. Buildings 2013-02-22 3 1 Article 10.3390/buildings3010245 245 257 2075-5309 2013-02-22 doi: 10.3390/buildings3010245 Henrik Davidsson Ricardo Bernardo Bengt Hellström http://www.mdpi.com/2075-5309/3/1/220 The UK government, responding to concerns over climate change impacts, has undertaken to reduce CO2 emissions to 80% of 1990 levels by 2050. This scale of reduction will require major improvements in the energy efficiency of the existing UK building stock, which is the dominant consumer of fossil fuel-generated energy. Housing is a key sector, and since 70% of all current homes in the UK will still exist in 2050 then low carbon refurbishment is critical if CO2 reduction goals are to be met. This paper uses computer modeling to examine the annual operational energy performance, long term energy cost savings and internal thermal conditions for a 19th century terraced house that was eco-refurbished to near a Passivhaus standard. The dwelling was modeled for three locations (Edinburgh, Manchester and London) using current and future climate scenarios (2020s and 2050s under high carbon emission scenarios). Simulation results suggest that there would be very little diminution in heating demand in the future for the house with no refurbishment, whilst the eco-refurbishment produced a significant reduction in energy demand and CO2 emissions. Analysis of the payback period and net present value indicate that the economic optimum varies according to energy prices and that the high construction costs incurred for an eco-refurbishment to a near Passivhaus standard could not be justified in terms of a cost/benefit analysis. Buildings 2013-02-21 3 1 Article 10.3390/buildings3010220 220 244 2075-5309 2013-02-21 doi: 10.3390/buildings3010220 Haniyeh Mohammadpourkarbasi Steve Sharples http://www.mdpi.com/2075-5309/3/1/205 The recycling of steel chips into an environmentally friendly, responsive, and profitable commodity in the manufacturing and construction industries is a huge and difficult challenge. Several strategies designed for the management and processing of this waste in developed countries have been largely unsuccessful in developing countries mainly due to its capital-intensive nature. To this end, this investigation attempts to provide an alternative solution to the recycling of this material by maximizing its utility value in the building construction industry. This is to establish their influence on the compressive strength of sandcrete hollow blocks and solid cubes with the aim of specifying the range percent of steel chips for the sandcrete optimum compressive strength value. This is particularly important for developing countries in sub-Saharan Africa, and even Latin America where most sandcrete blocks exhibit compressive strengths far below standard requirements. Percentages of steel chips relative to the weight of cement were varied and blended with the sand in an attempt to improve the sand grading parameters. The steel chips variations were one, two, three, four, five, ten and fifteen percent respectively. It was confirmed that the grading parameters were improved and there were significant increases in the compressive strength of the blocks and cube samples. The greatest improvement was noticed at four percent steel chips and sand combination. Using the plotted profile, the margin of steel chips additions for the optimum compressive strength was also established. It is recommended that steel chip sandcrete blocks are suitable for both internal load bearing, and non-load bearing walls, in areas where they are not subjected to moisture ingress. However, for external walls, and in areas where they are liable to moisture attack after laying, the surfaces should be well rendered. Below ground level, the surfaces should be coated with a water proofing agent like bitumen and cement containing waterproofing agents be used in the manufacture, laying, and rendering of steel chip sandcrete blocks. Buildings 2013-02-18 3 1 Article 10.3390/buildings3010205 205 219 2075-5309 2013-02-18 doi: 10.3390/buildings3010205 Alohan Omoregie http://www.mdpi.com/2075-5309/3/1/191 Following years of research and design in architecture under bio-climatic, sustainable and passive-energy concepts, today’s buildings are often well designed and constructed, responding to determined climate conditions and the user’s requirements for comfort and, in some cases, they are integrated into the urban environment. However, the lifetime of a building can be over 100 years and the climate is changing rapidly. This work investigates the impact of climate change future (2040 and 2070) on the energy consumption of residential buildings recently constructed, under three possible scenarios. The scenarios are created considering a low, medium or strong effect of global warming. Two types of buildings, with comparable consumption results of today, are investigated in three different cities around the world with a multi-zone type 56 of Trnsys simulation tool. At the end of the work, the concepts of energy robustness and global thermal effusivity of buildings are discussed as important strategies to reduce the possible impact of climate change on the built environment. The use of simulation tools to estimate the sensitivity of buildings is also analyzed, taking into consideration the recent goals of applying uncertainty and sensitivity analysis to building performance simulation science. Buildings 2013-02-07 3 1 Article 10.3390/buildings3010191 191 204 2075-5309 2013-02-07 doi: 10.3390/buildings3010191 Massimo Palme Antoni Isalgué Helena Coch http://www.mdpi.com/2075-5309/3/1/173 Reinforced concrete buildings suffered significant damage in the region affected by the 29 May 2011 earthquake in Simav (Kutahya), Turkey. Typical building damage is classified and potential causes of damage are investigated. Reinforced concrete moment resisting frames with hollow brick infill walls are the most common structural system in and around the Simav city center while masonry construction is common in rural areas. Although the Simav earthquake, with a magnitude of 5.7 to 5.9, can be classified as a moderate earthquake, many buildings experienced damage varying from frequent diagonal cracking and brittle failure of infill walls to collapse or severe damage to frames due to short columns, soft stories or other reasons including insufficient or poor detailing of reinforcement. This study investigates and presents the seismicity of the region, characteristics of the measured ground motions, seismic load demands including response spectra, and damage mechanisms, potential causes and classification of observed damage in reinforced concrete buildings. Buildings 2013-02-06 3 1 Article 10.3390/buildings3010173 173 190 2075-5309 2013-02-06 doi: 10.3390/buildings3010173 Adem Doğangün Ali Ural Halil Sezen Yücel Güney Fatih Fırat http://www.mdpi.com/2075-5309/3/1/143 The industrial and economic expansion of China, particularly its rapid urbanization, has resulted in dramatic increased consumption of energy resources and the resulting environmental impacts at local, regional and global levels. Although a national program aimed at the technological development of sustainable buildings with energy saving potential is ongoing, it is also appropriate to consult vernacular architectural tradition. This holds the potential to learn and adapt important cultural ideas developed over time on the art of balancing thermal comfort between climate and limited resources. This paper explores the five different climatic regions into which China is partitioned by the Chinese authorities: severe cold region, cold region, moderate region, hot summer and cold winter region, and hot summer and mild winter region. Analysis of each region covers the climate and its vernacular architecture with a special focus on how sustainability was addressed. Finally, regional climate scenario has been analyzed on the basis of data from Meteonorm V6.1 with special attention paid to passive design strategies. Buildings 2013-01-31 3 1 Review 10.3390/buildings3010143 143 172 2075-5309 2013-01-31 doi: 10.3390/buildings3010143 Feifei Sun http://www.mdpi.com/2075-5309/3/1/122 Resource depletion and global warming dictate needs to reduce energy consumption, however energy used for the environmental space conditioning of buildings remains substantial; even in well-designed examples. Therefore the ways in which buildings are utilized, and occupant expectations of comfort in building environments should be researched to determine alternative means for optimizing performance. This paper deals with transition spaces (entrance foyers, circulation zones, lift lobbies, stairways and atria) and thermal comfort experiences. It both reviews existing reported research into comfort in such spaces, and introduces new information from a range of studies completed in recent years. It assesses the usefulness and applicability of design standards which exist, but which are primarily concerned with more permanently (rather than transitorily) occupied spaces within buildings. Three main categories of transition space are identified: entrance zones; circulation zones; and zones of longer residence-time such as atria. The analysis indicates that different design standards, or variations on existing standards, should be considered for application in each type of space. The outcomes of this work suggest opportunities to reduce environmental conditioning and therefore energy use in such spaces; spaces which can make up a significant fraction of the overall floor area/volume of workplace buildings. Buildings 2013-01-23 3 1 Article 10.3390/buildings3010122 122 142 2075-5309 2013-01-23 doi: 10.3390/buildings3010122 Adrian Pitts http://www.mdpi.com/2075-5309/3/1/100 The aim of this paper is twofold: (a) to briefly describe the damage caused to historical, residential and industrial buildings by the May 2012 seismic events in the Emilia Romagna region of Italy; and (b) to summarize novel repair and rehabilitation technologies that can be available to practitioners to fix damaged structures or to upgrade undamaged ones. Field inspections after the Emilia Romagna earthquakes showed that seismic vulnerability in that region was primarily due to the lack of seismic detailing in modern buildings, and the presence of heavy nonstructural masses in historical buildings. The novel retrofit technologies discussed in this paper are based on the use of non-conventional or relatively recent material systems where the reinforcement is in the form of continuous or chopped fibers. Buildings 2013-01-21 3 1 Article 10.3390/buildings3010100 100 121 2075-5309 2013-01-21 doi: 10.3390/buildings3010100 Nicola Augenti Antonio Nanni Fulvio Parisi http://www.mdpi.com/2075-5309/3/1/79 Hemp concrete is a sustainable lightweight concrete that became popular in the field of building construction because of its thermal and environmental properties. However; available experimental data on its hygrothermal behavior are rather scarce in the literature. This paper describes the design of a large-scale experiment developed to investigate the hygrothermal behavior of hemp concrete cast around a timber frame through a spraying process; and then coated with lime-based plaster. The equipment is composed of two climatic chambers surrounding the tested wall. The experiment consists of maintaining the indoor climate at constant values and applying incremental steps of temperature; relative humidity or vapor pressure in the outdoor chamber. Temperature and relative humidity of the room air and on various depths inside the wall are continuously registered during the experiments and evaporation phenomena are observed. The influence of the plaster on the hygrothermal behavior of hemp concrete is investigated. Moreover; a comparison of experimental temperatures with numerical results obtained from a purely conductive thermal model is proposed. Comparing the model with the measured data gave satisfactory agreement. Buildings 2013-01-18 3 1 Article 10.3390/buildings3010079 79 99 2075-5309 2013-01-18 doi: 10.3390/buildings3010079 Thibaut Colinart Patrick Glouannec Thomas Pierre Philippe Chauvelon Anthony Magueresse http://www.mdpi.com/2075-5309/3/1/61 This study examines the need in mild maritime climates, such as the southern areas of the UK, for mechanical ventilation with heat recovery (MVHR) as required by the German Passivhaus standard. It considers the comfort, air quality and energy impacts of MVHR versus natural ventilation and reviews the post-occupancy monitoring data of two flats in Cardiff designed to Passivhaus standards, one of which had been operated as a naturally ventilated building rather than with MVHR. The energy consumption of this free-running flat was significantly lower (36 kWh primary energy/m²a) than the Passivhaus Planning Package modeling had predicted (93 kWh primary energy/m²a) with no adverse effects on occupant comfort, air quality or excessive humidity, and advantages of lower capital cost and maintenance. The paper concludes that in climates with mild winters and cool summers the use of MVHR could be omitted without compromising comfort levels and achieving at least equivalent energy savings resulting from adopting the Passivhaus model and at a lower capital cost. This suggests the potential for a naturally ventilated, ultra-low energy model with lower capital investment requirements and lower disruption when applied to retrofit that would facilitate its mainstream adoption. Buildings 2013-01-18 3 1 Article 10.3390/buildings3010061 61 78 2075-5309 2013-01-18 doi: 10.3390/buildings3010061 Paola Sassi http://www.mdpi.com/2075-5309/3/1/39 Understanding how Building Environmental Assessments Tools (BEATs) measure and define “environmental” building is of great interest to many stakeholders, but it is difficult to understand how BEATs relate to each other, as well as to make detailed and systematic tool comparisons. A framework for comparing BEATs is presented in the following which facilitates an understanding and comparison of similarities and differences in terms of structure, content, aggregation, and scope. The framework was tested by comparing three distinctly different assessment tools; LEED-NC v3, Code for Sustainable Homes (CSH), and EcoEffect. Illustrations of the hierarchical structure of the tools gave a clear overview of their structural differences. When using the framework, the analysis showed that all three tools treat issues related to the main assessment categories: Energy and Pollution, Indoor Environment, and Materials and Waste. However, the environmental issues addressed, and the parameters defining the object of study, differ and, subsequently, so do rating, results, categories, issues, input data, aggregation methodology, and weighting. This means that BEATs measure “environmental” building differently and push “environmental” design in different directions. Therefore, tool comparisons are important, and the framework can be used to make these comparisons in a more detailed and systematic way. Buildings 2013-01-17 3 1 Article 10.3390/buildings3010039 39 60 2075-5309 2013-01-17 doi: 10.3390/buildings3010039 Marita Wallhagen Mauritz Glaumann Ola Eriksson Ulla Westerberg http://www.mdpi.com/2075-5309/3/1/18 A key component in low energy houses is the heat recovery from the ventilation air. Over recent years, the most frequently used ventilation type is the mechanical ventilation with heat recovery. This kind of ventilation results in high heat recovery but does unfortunately consume a considerable amount of electrical energy. Natural or hybrid ventilation has the potential to consume less electricity but normally lacks heat recovery, leading to high-energy consumption for heating, and potentially low comfort. This article describes an investigation of a natural/hybrid ventilation system equipped with heat recovery. One of the key challenges in designing the heat exchanger is to keep the pressure drop low. At the same time the heat recovery rate has to be high. The results from the measurements show that it is possible to design a water-to-air heat exchanger with a temperature efficiency of approximately 80% with a pressure drop of about 1 Pa at air flows corresponding to 0.35 L/(s∙m²) building area. This type of ventilation system has the potential to offer a high thermal comfort, high heat recovery rate at the same time as the electrical consumption from fans is kept low. Old buildings with a natural ventilation system without heat recovery could also be retrofitted with this type of ventilation system. Buildings 2013-01-14 3 1 Article 10.3390/buildings3010018 18 38 2075-5309 2013-01-14 doi: 10.3390/buildings3010018 Henrik Davidsson Ricardo Bernardo Bengt Hellström http://www.mdpi.com/2075-5309/3/1/1 The cooperative housing sector is directed at low and medium income residents who cannot afford to buy their homes in the regular private market. Due to social housing legislation, it is possible to build cooperative housing below regular market costs and use tax benefits, therefore providing affordable dwellings to their owners. Traditional cooperative housing used to provide less comfort and higher running costs in indoor and domestic hot water heating than in standard construction. However, cooperative housing has started to change its method of traditional construction towards sustainable construction, in order to benefit from the savings on energy consumption and domestic water as well as to provide an improvement as far as the comfort of its residents is concerned. Therefore, in this article, the savings in electricity and natural gas in different building settlements, calculated for Madalena building—sustainable construction—and for Azenha de Cima building—traditional construction—will be presented, according to two different criteria of calculation: efficiency of dwellings at a pre-determined standard level of indoor comfort opposed to real consumptions made by residents. For each building under analysis, an energy audit and further monitoring were brought in, in order to issue an energy evaluation according to the Portuguese energy agency rules. Results showed an expected decrease of the operational costs of natural gas and electricity, obtained by the use of efficient building systems and equipment, as well as a decrease of the payback period for each situation. Buildings 2013-01-04 3 1 Article 10.3390/buildings3010001 1 17 2075-5309 2013-01-04 doi: 10.3390/buildings3010001 José Coimbra Manuela Almeida http://www.mdpi.com/2075-5309/2/4/542 Window frame material has significant impact on the thermal performance of the window. Moreover, with sustainable design becoming a necessity, window frame materials need to have higher levels of environmental performance to be considered sustainable. As a result, a holistic performance metric is needed to assess window frame material. Three similar frames were considered, manufactured from aluminum, polyvinyl chloride (PVC), and wood. First their thermal performance was evaluated and compared using a heat transfer model. Then, carbon footprints of the three materials were considered for 1m2 of window area with a similar thermal performance. It was found that the thermal, as well as the environmental, performance of the wooden window frame was superior to those of aluminum and PVC. On the other hand aluminum frames had high environmental impacts and comparatively lower thermal performance. This study provides a holistic viewpoint on window frames by considering both environmental and thermal performance. Buildings 2012-12-12 2 4 Article 10.3390/buildings2040542 542 553 2075-5309 2012-12-12 doi: 10.3390/buildings2040542 Arijit Sinha Andreja Kutnar http://www.mdpi.com/2075-5309/2/4/534 The natatorium enclosure at the Avon Recreation Center in Avon, Colorado experienced significant deterioration of the CMU façade due to moisture carried by humid air from the interior of the space into the wall assembly. This situation was caused by a combination of an insufficient interior air and vapor barrier along with an HVAC system that failed to provide negative pressurization to the space. This case study describes the investigation carried out to determine the causes of wall and roof deterioration at the building, and details the repair efforts undertaken. Lessons learned are presented to help designers, building owners, and maintenance personnel prevent similar problems from occurring in their buildings. Buildings 2012-12-12 2 4 Case Report 10.3390/buildings2040534 534 541 2075-5309 2012-12-12 doi: 10.3390/buildings2040534 Lawrence Graham Mark Scott Aleka Pappas http://www.mdpi.com/2075-5309/2/4/519 Tornadoes are a particularly devastating natural hazard that affect communities across the United States, particularly the Midwest and South. They are unique from an engineering point-of-view due to their very low probability of occurrence but often highly destructive consequences. The 2011 season was particularly devastating to the Southeastern portion of the U.S. This paper presents a single case study of a 2012 tornado that struck a single large rural light-frame wood house with an unconventional roof system. A fragility methodology was used as a tool to probabilistically study the loss of the roof system, and bound an Enhanced Fujita (EF) scale rating of the tornado. The tornado was initially rated as an EF3 tornado by the U.S. National Weather Service. However, following a detailed site inspection verified with numerical structural models, the tornado was downgraded to an EF2 tornado. As expected, the use of nail connections in a roof-to-wall connection resulted in a weaker link compared to a hurricane clip. The approach presented in this paper can be used as a supplement to the EF rating provided by U.S. National Weather Service meteorologists when unusual conditions in either the structure or surroundings exists. Buildings 2012-12-11 2 4 Article 10.3390/buildings2040519 519 533 2075-5309 2012-12-11 doi: 10.3390/buildings2040519 John van de Lindt Mohammad Amini Christine Standohar-Alfano Thang Dao http://www.mdpi.com/2075-5309/2/4/497 Over the past decade, much research has focused on the behaviour of structures following the failure of a key structural component. Particular attention has been given to sudden column loss, though questions remain as to whether this event-independent scenario is relevant to actual extreme events such as explosion. Few studies have been conducted to assess the performance of floor slabs above a failed column, and the computational tools used have not been validated against experimental results. The research program presented in this paper investigates the adequacy of sudden column loss as an idealisation of local damage caused by realistic explosion events, and extends prior work by combining the development of accurate computational models with large-scale testing of a typical floor system in a prototypical steel-framed structure. The floor system consists of corrugated decking topped by a lightly reinforced concrete slab that is connected to the floor beams through shear studs. The design is consistent with typical building practices in the US. The first test has been completed, and subsequent tests are currently being planned. This paper addresses the importance of robustness design for localized damage and includes a detailed description regarding how the research program advances the current state of knowledge for assessing robustness of compositely constructed steel-framed buildings. Buildings 2012-12-11 2 4 Article 10.3390/buildings2040497 497 518 2075-5309 2012-12-11 doi: 10.3390/buildings2040497 Hamed Zolghadr Jahromi Bassam Izzuddin David Nethercot Sean Donahue Michalis Hadjioannou Eric Williamson Michael Engelhardt David Stevens Kirk Marchand Mark Waggoner http://www.mdpi.com/2075-5309/2/4/477 This paper analyzes the historical consumption of natural gas in a multifamily high-rise building and the monitored winter thermal behavior of an apartment sample. The building is located in the center of Argentina (latitude: 36º27’S; longitude: 64º27’W), where the climate is a cold temperate with an absolute minimum temperature that may reach −10 °C. The building has two blocks, North and South. The building’s annual gas consumption and its variability between 1996 and 2008 are shown. The South block consumed 78% more gas, a situation expected due to lower solar resource availability and greater vulnerability regarding strong and cold SW winds. Indoor temperatures monitored during 2009 in four apartments are described. The outdoor minimum temperature reached −5 °C, with solar irradiance around 500 W/m2 at midday. Results showed that the average indoor temperatures were 20.1, 20.6, 24.0 and 22.1 °C. The highest consumption value corresponded to the apartment exposed to SW cold winds. Compared to the rest of the building, the apartment on the top floor consumes 59% more energy than the average for the gas consumed throughout the year. The authors assume that the energy potentials of intervention are different, and not necessarily all the apartments should have the same technological response. Buildings 2012-12-04 2 4 Article 10.3390/buildings2040477 477 496 2075-5309 2012-12-04 doi: 10.3390/buildings2040477 Celina Filippín Silvana Larsen http://www.mdpi.com/2075-5309/2/4/456 This paper reviews the results of a comprehensive investigation including more than 100 fatigue damage cases, reported for steel and composite bridges. The damage cases are categorized according to types of detail. The mechanisms behind fatigue damage in each category are identified and studied. It was found that more than 90% of all reported damage cases are of deformation-induced type and generated by some kind of unintentional or otherwise overlooked interaction between different load-carrying members or systems in the bridge. Poor detailing, with unstiffened gaps and abrupt changes in stiffness at the connections between different members were also found to contribute to fatigue cracking in many details. Buildings 2012-11-12 2 4 Article 10.3390/buildings2040456 456 476 2075-5309 2012-11-12 doi: 10.3390/buildings2040456 Reza Haghani Mohammad Al-Emrani Mohsen Heshmati http://www.mdpi.com/2075-5309/2/4/424 This paper describes some methods for producing developable surfaces with practical applications for creating useful lightweight, rigid, jig-less and elegant structural forms from sheet materials. Multiple related techniques based on the same fundamental principle can be used to generate a variety of interesting singly curved and doubly curved shapes. The system requires a minimum of specialist software, and is described in simple steps that can be followed by the reader with access to basic 3D CAD tools. Buildings 2012-10-19 2 4 Article 10.3390/buildings2040424 424 455 2075-5309 2012-10-19 doi: 10.3390/buildings2040424 Bruno Postle http://www.mdpi.com/2075-5309/2/4/384 The tall building is the most dominating symbol of the cities and a human-made marvel that defies gravity by reaching to the clouds. It embodies unrelenting human aspirations to build even higher. It conjures a number of valid questions in our minds. The foremost and fundamental question that is often asked: Why tall buildings? This review paper seeks to answer the question by laying out arguments against and for tall buildings. Then, it provides a brief account of the historic and recent developments of tall buildings including their status during the current economic recession. The paper argues that as cities continue to expand horizontally, to safeguard against their reaching an eventual breaking point, the tall building as a building type is a possible solution by way of conquering vertical space through agglomeration and densification. Case studies of some recently built tall buildings are discussed to illustrate the nature of tall building development in their respective cities. The paper attempts to dispel any discernment about tall buildings as mere pieces of art and architecture by emphasizing their truly speculative, technological, sustainable, and evolving nature. It concludes by projecting a vision of tall buildings and their integration into the cities of the 21st century. Buildings 2012-09-28 2 4 Article 10.3390/buildings2040384 384 423 2075-5309 2012-09-28 doi: 10.3390/buildings2040384 Mir M. Ali Kheir Al-Kodmany http://www.mdpi.com/2075-5309/2/3/359 Nonlinear numerical simulations are reported for a conventional unitized laminated glass curtain wall subjected to high- and low-level air blast loading. The studied curtain wall, spanning floor to floor, consisted of a laminated glass panel, a continuous bead of structural silicone sealant, a split screw spline frame and four rigid brackets. Firstly, a linear elastic FE-model (M01) is presented to investigate dynamic stresses and deflections due to explosion, by taking into account geometrical nonlinearities. Since, in similar glazing systems, it is important to take into account the possible cracking of glass lites, a second model (M02), calibrated to previous experimental data, is proposed. In it, glass behaves as a brittle-elastic material, whereas an elastoplastic characteristic curve is assumed for mullions. As a result, the design explosion seriously affects the main components of the curtain wall, especially the bead of silicone. To address these criticalities, additional viscoelastic (VE) devices are installed at the frame corners (M03). Their effectiveness explains the additional deformability provided to the conventional curtain wall, as well as the obvious dissipation of the incoming energy due to blast loading. Structural and energy capabilities provided by devices are highlighted by means of numerical simulations. Buildings 2012-09-18 2 3 Article 10.3390/buildings2030359 359 383 2075-5309 2012-09-18 doi: 10.3390/buildings2030359 Claudio Amadio Chiara Bedon http://www.mdpi.com/2075-5309/2/3/332 A multidisciplinary approach for assessing the seismic vulnerability of heritage masonry buildings is described throughout the paper. The procedure is applied to a specific case study that represents a very common typology of masonry building in Italy. The seismic vulnerability of the examined building was assessed after the following: (a) historical investigation about the building and the surrounding area, (b) detailed geometrical relieves, (c) identification of materials by means of surveys and literature indications, (d) dynamic in-situ tests, (e) foundation soil characterization, (f) dynamic identification of the structure by means of a refined Finite Element (FE) model. After these steps, the FE model was used to assess the safety level of the building by means of non-linear static analyses according to the provisions of Eurocode 8 and estimate of the q-factor. Some parametric studies were also carried out by means of both linear dynamic and non-linear static analyses. Buildings 2012-09-13 2 3 Article 10.3390/buildings2030332 332 358 2075-5309 2012-09-13 doi: 10.3390/buildings2030332 Francesca Ceroni Marisa Pecce Stefania Sica Angelo Garofano http://www.mdpi.com/2075-5309/2/3/326 Most building professionals have investigated or performed remedial designs for at least one architectural or engineering system failure during their careers. Other practitioners, especially those who work for forensic consultants or firms specializing in disaster response and repair, are more familiar with the variety and extent of building failures as they assist their clients in restoring damaged or deficient buildings. The advent of social medial and twenty-four-hour news channels along with the general ease of finding more examples of failures in the Internet have made us realize that building failures in the broad sense are much more common than we may have realized.Relatively recent events leading to building failures such as the Christchurch, New Zealand earthquakes, the roof/parking deck of the Algo Centre mall in the northern Ontario, Canada city of Elliot Lake and the Indiana State Fairground stage collapse in the US are just a few reminders that much more work needs to be done on a variety of fronts to prevent building failures from a life safety standpoint. The need is compounded by economic concerns from what would be considered more mundane or common failures. Inspections by the author after Hurricane Katrina revealed a huge number of failures associated rain water alone as roofs, windows, flashing, mechanical penetrations etc. failed leading to interior water penetration often resulting in more damage from damp conditions and mold propagation than outright structural collapses. Buildings 2012-09-05 2 3 Editorial 10.3390/buildings2030326 326 331 2075-5309 2012-09-05 doi: 10.3390/buildings2030326 M. Kevin Parfitt http://www.mdpi.com/2075-5309/2/3/300 Seismic isolation is a technique that has been used around the world to protect building structures, nonstructural components and content from the damaging effects of earthquake ground shaking. This paper summarizes current practices, describes widely used seismic isolation hardware, chronicles the history and development of modern seismic isolation through shake table testing of isolated buildings, and reviews past efforts to achieve three-dimensional seismic isolation. The review of current practices and past research are synthesized with recent developments from full-scale shake table testing to highlight areas where research is needed to achieve full seismic damage protection of buildings. The emphasis of this paper is on the application of passive seismic isolation for buildings primarily as practiced in the United States, though systems used in other countries will be discussed. Buildings 2012-08-03 2 3 Review 10.3390/buildings2030300 300 325 2075-5309 2012-08-03 doi: 10.3390/buildings2030300 Gordon P. Warn Keri L. Ryan http://www.mdpi.com/2075-5309/2/3/283 This paper examines contemporary issues in building collapse and its implications for sustainable development in Nigeria. It explores whether the approach to construction by industry stakeholders is in line with the principles of sustainable development following the spate of building collapses in Nigeria. The rationale for the investigation stems from the view by scholars that construction industry stakeholders’ do not seem to consider the future in their current activities. The study establishes that the approach to construction by industry stakeholders do not match sustainable principles, and contributes to general under perforxmance of buildings. The paper recommends an overhaul of planning and implementation policies for building development regulations (e.g., building codes). The Nigerian government, as a major construction stakeholder should initiate sustainable construction measures and enforce this as best practice for the construction industry. Buildings 2012-07-25 2 3 Article 10.3390/buildings2030283 283 299 2075-5309 2012-07-25 doi: 10.3390/buildings2030283 Abimbola O. Windapo James O. Rotimi http://www.mdpi.com/2075-5309/2/3/271 In the last few years, the need to evaluate the seismic performances of buildings on sustaining strong motion has encouraged the development of simplified non-linear static analyses. Several procedures are available today to assess the behavior of plane-frame systems or plan-regular framed buildings suitable for engineering purposes. Less accurate procedures are instead available for irregular structures. This study introduces new tools to assess the seismic performance of irregular structures by using capacity domains and polar spectra. In particular, the capacity domains, plotted in terms of base shear and node control displacements and obtained by means of static non-linear analyses, lead to the evaluation of the direction of least seismic capacity of the investigated structure. The polar spectrum, instead, leads to taking into account the directivity and site effects of seismic events. In particular, the polar spectrum represents the spectral seismic response evaluated for different in-plan directions. Buildings 2012-07-18 2 3 Article 10.3390/buildings2030271 271 282 2075-5309 2012-07-18 doi: 10.3390/buildings2030271 Luigi Petti Ivana Marino http://www.mdpi.com/2075-5309/2/3/245 The objective of this project was to quantify and compare the environmental impacts associated with alternative designs for a typical North American mid-rise office building. Two scenarios were considered; a traditional cast-in-place, reinforced concrete frame and a laminated timber hybrid design, which utilized engineered wood products (cross-laminated timber (CLT) and glulam). The boundary of the quantitative analysis was cradle-to-construction site gate and encompassed the structural support system and the building enclosure. Floor plans, elevations, material quantities, and structural loads associated with a five-storey concrete-framed building design were obtained from issued-for-construction drawings. A functionally equivalent, laminated timber hybrid design was conceived, based on Canadian Building Code requirements. Design values for locally produced CLT panels were established from in-house material testing. Primary data collected from a pilot-scale manufacturing facility was used to develop the life cycle inventory for CLT, whereas secondary sources were referenced for other construction materials. The TRACI characterization methodology was employed to translate inventory flows into impact indicators. The results indicated that the laminated timber building design offered a lower environmental impact in 10 of 11 assessment categories. The cradle-to-gate process energy was found to be nearly identical in both design scenarios (3.5 GJ/m2), whereas the cumulative embodied energy (feedstock plus process) of construction materials was estimated to be 8.2 and 4.6 GJ/m2 for the timber and concrete designs, respectively; which indicated an increased availability of readily accessible potential energy stored within the building materials of the timber alternative. Buildings 2012-07-17 2 3 Article 10.3390/buildings2030245 245 270 2075-5309 2012-07-17 doi: 10.3390/buildings2030245 Adam B. Robertson Frank C. F. Lam Raymond J. Cole http://www.mdpi.com/2075-5309/2/3/231 A finite element model is developed to analyse, as a function of volume fraction, the effects of reinforcement geometry and arrangement within a timber beam. The model is directly validated against experimental equivalents and found to never be mismatched by more than 8% in respect to yield strength predictions. Yield strength increases linearly as a function of increasing reinforcement volume fraction, while the flexural modulus follows more closely a power law regression fit. Reinforcement geometry and location of reinforcement are found to impact both the flexural properties of timber-steel composite beams and the changes due to an increase in volume fraction. Buildings 2012-07-10 2 3 Article 10.3390/buildings2030231 231 244 2075-5309 2012-07-10 doi: 10.3390/buildings2030231 Parvez Alam Martin Ansell Dave Smedley http://www.mdpi.com/2075-5309/2/3/218 Seismic assessment of masonry structures is plagued by both inherent randomness and model uncertainty. The former is referred to as aleatory uncertainty, the latter as epistemic uncertainty because it depends on the knowledge level. Pioneering studies on reinforced concrete buildings have revealed a significant influence of modeling parameters on seismic vulnerability. However, confidence in mechanical properties of existing masonry buildings is much lower than in the case of reinforcing steel and concrete. This paper is aimed at assessing whether and how uncertainty propagates from material properties to seismic capacity of an entire masonry structure. A typical two-story unreinforced masonry building is analyzed. Based on previous statistical characterization of mechanical properties of existing masonry types, the following random variables have been considered in this study: unit weight, uniaxial compressive strength, shear strength at zero confining stress, Young’s modulus, shear modulus, and available ductility in shear. Probability density functions were implemented to generate a significant number of realizations and static pushover analysis of the case-study building was performed for each vector of realizations, load combination and lateral load pattern. Analysis results show a large dispersion in displacement capacity and lower dispersion in spectral acceleration capacity. This can directly affect decision-making because both design and retrofit solutions depend on seismic capacity predictions. Therefore, engineering judgment should always be used when assessing structural safety of existing masonry constructions against design earthquakes, based on a series of seismic analyses under uncertain parameters. Buildings 2012-07-06 2 3 Article 10.3390/buildings2030218 218 230 2075-5309 2012-07-06 doi: 10.3390/buildings2030218 Fulvio Parisi Nicola Augenti http://www.mdpi.com/2075-5309/2/3/203 Design is a social phenomenon and researchers suggest that social interaction, negotiations and communication between designers are essential to initiate creativity. Within the design studio environment, a number of factors affect the healthy social interaction and design negotiations, such as the teaching style of tutors and the culture that governs a design studio’s environment. This may in turn affect the utilization of the outcome of negotiations in the design project. Design studio students from the third to fifth years at the College of Architecture, University of Dammam (UD), the Kingdom of Saudi Arabia (KSA), were surveyed to find out how far the design studio’s culture and communication would impact the production of innovative design projects. The results show that frequent communication and the establishment’s shared grounds are essential to develop knowledge and positively influence the design outcome. On the other hand, the research found that negative qualities on a personal level and on that of a design studio environment would hinder a student’s creativity. However, to develop students’ design/innovative abilities, the researcher recommends that certain measures should be considered. These would include transforming the design studio into an interactive and friendly learning environment, adjusting the teaching methodology, and developing interactive communication abilities of students and tutors. Buildings 2012-07-05 2 3 Article 10.3390/buildings2030203 203 217 2075-5309 2012-07-05 doi: 10.3390/buildings2030203 Bhzad Sidawi http://www.mdpi.com/2075-5309/2/3/173 A key element in the seismic load resisting system of a wood framed structure is the shear wall which is typically sheathed on one side with plywood or oriented strand board (OSB) and gypsum on the other. The shear capacity of gypsum sheathed shear walls is typically neglected in high seismic areas due to the susceptibility of conventional drywall screw connections to damage caused by earthquakes. The earthquake resistance of an innovative viscoelastic (VE) gypsum shearwall is evaluated and compared to conventional structural and non-structural walls. Ten 8 ft × 8 ft wood framed wall specimens of three configurations [nailed-OSB, screw-gypsum, and VE polymer-gypsum] were subjected to a cyclic test protocol. The energy dissipation, stiffness, and damage characteristics of all shearwalls are reported herein. Testing results indicate the VE-gypsum walls can dissipate more energy than the OSB structural panels and 500% more energy that the conventional gypsum sheathed walls and contains a constant source of energy dissipation not seen in the structural and non-structural walls. The wall stiffness of the OSB wall degrades at a far greater rate that the VE gypsum wall and at continued cycling degrades below the VE wall stiffness. Unlike both of the conventional wall types, the VE wall showed no visible or audible signs of damage when subjected to shear displacements up to 1. Buildings 2012-06-28 2 3 Article 10.3390/buildings2030173 173 202 2075-5309 2012-06-28 doi: 10.3390/buildings2030173 David W. Dinehart Andrew S. Blasetti http://www.mdpi.com/2075-5309/2/2/153 The majority of the sandcrete blocks used in the Nigerian building industry fall short of the minimum specification standards. There is evidence to suggest a wide variation in compressive strength from one block manufacturer to another and also within block samples from a single source. This problem has been attributed to poor quality control and substandard constituent materials. Also very alarming is the ignorance surrounding the usage and engineering properties of some of the widely used fine aggregate deposits. As a way forward, this paper aims to re-establish the impact of vibration time in sandcrete block production using six fine aggregate deposits found within Benin City (Midwestern Nigeria) and their various pair combinations. Some of the basic properties like silt content, grading parameters—co-efficient of uniformity (Cu), curvature co-efficient (Cc) and the fineness modulus (Fm)—of these fine aggregates were established by laboratory means. In addition, the wet and dry compressive strength of these sandcrete blocks made from these sands were established. A total of 1,080 block samples produced under very controlled conditions were used in this investigation. It was revealed that the utility value of sand can be improved when the weaker and commonly used sands were combined with those that are better, more expensive and less frequently used at different vibration periods and ratios. Findings further revealed that sand types and the sand combination approach adopted were very significant to grading parameters and strength; at a much higher vibration time the compressive strength and durability properties were also considerably improved. Buildings 2012-05-09 2 2 Article 10.3390/buildings2020153 153 172 2075-5309 2012-05-09 doi: 10.3390/buildings2020153 Alohan Omoregie http://www.mdpi.com/2075-5309/2/2/126 This paper presents a conceptual framework aimed at implementing sustainability principles in the building industry. The proposed framework based on the sustainable triple bottom line principle, includes resource conservation, cost efficiency and design for human adaptation. Following a thorough literature review, each principle involving strategies and methods to be applied during the life cycle of building projects is explained and a few case studies are presented for clarity on the methods. The framework will allow design teams to have an appropriate balance between economic, social and environmental issues, changing the way construction practitioners think about the information they use when assessing building projects, thereby facilitating the sustainability of building industry. Buildings 2012-05-04 2 2 Article 10.3390/buildings2020126 126 152 2075-5309 2012-05-04 doi: 10.3390/buildings2020126 Peter O. Akadiri Ezekiel A. Chinyio Paul O. Olomolaiye http://www.mdpi.com/2075-5309/2/2/107 Structures of Uniform Response are special earthquake resistant frames in which members of similar groups such as beams, columns and braces of similar nature share the same demand-capacity ratios regardless of their location within the group. The fundamental idea behind this presentation is that seismic structural response is largely a function of design and construction, rather than analysis. Both strength and stiffness are induced rather than investigated. Failure mechanisms and stability conditions are enforced rather than tested. Structures of Uniform Response are expected to sustain relatively large inelastic displacements during major earthquakes. A simple technique has been proposed to control and address the gradual softening of such structures due to local/partial instabilities and formation of plastic hinges. In structures of uniform response, the magnitude and shape of distribution of lateral forces affects the distribution of story stiffness in proportion with story moments, therefore affecting the dynamic behavior of the system as a whole. Simple closed form formulae describing the nonlinear behavior of moment frames of uniform response have been proposed. While the scope of this contribution is limited to moment frames, the proposed method can successfully be extended to all types of recognized earthquake resisting systems. Buildings 2012-05-02 2 2 Article 10.3390/buildings2020107 107 125 2075-5309 2012-05-02 doi: 10.3390/buildings2020107 Mark Grigorian Carl E. Grigorian http://www.mdpi.com/2075-5309/2/2/83 This paper reports on recent experience of engaging with building users who have communication difficulties, as a potential part of client briefing. The users were residents of a specialist Scottish Housing Association (HA) providing social housing and care services; the residents having a wide range of complex needs, predominantly learning difficulties. Many of these residents have communication difficulties, ranging from mild to very severe. The challenge presented was to effectively engage with a representative sample of residents to ascertain how they value their living environment. The researchers’ involvement was based on prior research into how different participants engage in the architectural design process. Buildings 2012-04-27 2 2 Article 10.3390/buildings2020083 83 106 2075-5309 2012-04-27 doi: 10.3390/buildings2020083 Paul Jenkins Iain Scott Andy Challen http://www.mdpi.com/2075-5309/2/2/63 Recent Italian earthquakes have underlined the need for wide monitoring and safety assessment of architectonical heritage. This has emerged also from requirements of the new Italian Technical Recommendations for buildings. Within this subject the paper investigates the seismic vulnerability of a specific monumental masonry building: the Vicarious Palace (Palazzo del Vicario) in Pescia, a small town near Florence. The structural behavior of the Palace was investigated using a finite element model in which the non-linearities of the masonry were considered by proper constitutive assumptions. The seismic behavior was evaluated by the pushover method, according to the Italian Technical Recommendations. The results were compared with the ones obtained by a simplified approach based on the kinematic theorem of limit analysis. Comparisons of the expected seismic demand vs the seismic capacity of the Palace confirm the weakness of this type of building to suffer extensive damage under earthquakes, as frequently observed in similar construction typologies. Additionally, the comprehension of the structural behavior under seismic loading allows the identification of a proper retrofitting strategy. Buildings 2012-04-24 2 2 Article 10.3390/buildings2020063 63 82 2075-5309 2012-04-24 doi: 10.3390/buildings2020063 Michele Betti Luciano Galano http://www.mdpi.com/2075-5309/2/2/43 The paper presents the features of Tall-building Projects Sustainability Indicator (TPSI)—a “Sustainability Rating System” that specializes in tall-building projects. The system comprises two components; the “Technical Manual” in the form of a booklet and the “Calculator” in the form of an Excel tool. It can be used as a “design tool” and/or as a “checklist” to compare and to improve the sustainable performance of tall-building design schemes. At the same time, the system can be used to evaluate the sustainability of existing tall-building projects. The first version of the TPSI rating system (TPSI 2012 Version) was released as an online tool (GreenLight) and thoroughly examined and validated by multiple parties. Buildings 2012-04-16 2 2 Article 10.3390/buildings2020043 43 62 2075-5309 2012-04-16 doi: 10.3390/buildings2020043 Binh K. Nguyen Hasim Altan http://www.mdpi.com/2075-5309/2/1/33 The authors investigated the occupants’ perceptions of 47 commercial and institutional buildings worldwide. These investigations involved the personal distribution and collection of a questionnaire survey seeking the occupants' perceptions (scored on a 7-point scale) of some 45 factors: Operational; Environmental (including temperature, air quality, lighting, and noise); Personal Control; and Satisfaction (including design, needs, comfort overall, productivity, and health). Occupants were also invited to comment on nine of these factors. While it has been suggested that in the ideal situation the occupants would have no complaints about their indoor environment, the aim here was to discover the real situation—in particular the proportion of occupants who were prepared to make a comment, the general nature of the comments (positive, negative, or balanced), and whether these correlated with the occupants’ perception scores. On average, 34 per cent of respondents took up the invitation to make a comment. As anticipated, the greater the number of positive comments, the better the perception score, and vice-versa. However, it appears that it only required around 20% of the comments to be positive for the perception score to exceed the mid-point of the seven-point scale, whereas 65% or more of negative comments were needed to go under that point. This paper details the nature of the correlation between the occupants’ comments and the corresponding scores for a range of building operational and indoor environmental factors and speculates on their potential for the analysis and prediction of building performance from the perspective of the occupants. Buildings 2012-01-27 2 1 Article 10.3390/buildings2010033 33 42 2075-5309 2012-01-27 doi: 10.3390/buildings2010033 George Baird Clare Dykes http://www.mdpi.com/2075-5309/2/1/1 Material selection is a complex and delicate task determined by the immense number of building material options. Likewise, multiple factors are often considered by the architect when evaluating the various categories of building materials. As a result, these sets of factors or variables often present tradeoffs that make the decision process even more complex. To ease the material-selection process, this article examines one aspect of the research objectives: the relevant factors or variables needed to develop a systematic and efficient material-selection system. Through the analysis of frequency data and results of a pilot study, it identifies some of the potential factors that will impact architects decisions in their choice of green vernacular building materials, during the design-decision making process. The application of the criteria for the quantitative evaluation and selection of the best alternative building material, using the Analytic Hierarchy Process (AHP) model, are discussed. The aim is to develop a multi-factorial analytical decision support toolkit to assist architects assess their consequences in terms of whether or not the material option is likely to move towards sustainability objectives. An example is included to illustrate the AHP approach. The argument is advanced that the explicit incorporation of sustainability in the material selection process requires the assessment of the social, economic, technical, sensorial and environmental consequences of potential material options. Buildings 2012-01-23 2 1 Article 10.3390/buildings2010001 1 32 2075-5309 2012-01-23 doi: 10.3390/buildings2010001 Ibuchim Ogunkah Junli Yang http://www.mdpi.com/2075-5309/1/1/4 Much of the residential sector in Spain is obsolete, with inadequate conditions of comfort and high energy consumption. For this reason most of the potential for improving energy efficiency lies in the existing residential sector, which requires upgrading to meet the quantitative and qualitative changes required at present. This study of specific cases aimed at establishing general criteria for action has been prompted by the difficulty in proposing general intervention strategies. This paper presents a case study for the energy retrofit of 68 social housing units in Cordoba (Spain) evaluating their energy consumption, with a view to improving the building’s energy balance and indoor thermal comfort, on which user comfort depends. Buildings 2011-12-27 1 1 Article 10.3390/buildings1010004 4 15 2075-5309 2011-12-27 doi: 10.3390/buildings1010004 Rafael Suárez Jessica Fernández-Agüera http://www.mdpi.com/2075-5309/1/1/1 People are estimated to spend 80–90% of their time in buildings—residences, offices, factories, schools, places of worship, public amenities, recreational facilities, etc. Thus buildings play a very important role in the lives of individuals and societies. However, they are often taken for granted, except for private residences which are dear to people for a variety of reasons. One of the consequences of this is that research into the development of buildings (science, design, materials, etc.) has not advanced at the same pace as other industry sectors. While the automobile and aerospace industries have considerably improved the efficiency of vehicles and aircraft, buildings have only recorded incremental improvements. However, the situation is beginning to change with several initiatives at industry, national and multi-national levels aimed at improving the efficiency of the construction industry and the quality of the buildings that it produces. In many cases, these initiatives and associated research efforts require interdisciplinary collaboration to tackle what is essentially a multi-facetted problem. There is scope to better disseminate the outcomes of these efforts in a coherent, inter-disciplinary journal. Buildings 2011-04-20 1 1 Editorial 10.3390/buildings1010001 1 3 2075-5309 2011-04-20 doi: 10.3390/buildings1010001 Chimay J. Anumba