Post-handover housing defects: sources and origins

In Spain, the high levels of inexperienced workers and the long chains of subcontracting contribute to the poor quality of dwellings. Althoughthe Ley reguladora de la subcontratación en el Sector de la Construcción (subcontracting law) has established quality measures, the number of customer complaints is still increasing. In this paper, a total of 2,351 posthandover defects derived from four Spanish builders and seven residential developments are classi fi ed according to their source and origin. The research reveals that the most common defects identi fi ed by customers at posthandover were derived from bad workmanship and were related to construction errors and omissions. Typical defects were foundtoincludeincorrectinstallation,appearancedefects,andmissinganitemortaskmainlyrelatedto fi nishingandconsideredtobeminor.No defects were caused by poor design because they are mainly detected and resolved during construction or become apparent after some years of use. This study demonstrates the negative impact of redoing defective work during the fi nal stages of construction and provides knowledge to de fi ne measures to improve the quality of the fi nished buildings, such as understanding customer expectations and preferences, training programs for workers, specialization of subcontractors, and tightening external controls prior to handover.Postprint (author's final draft

Reduced-order modeling for energy performance contracting

Buildings subject to Energy Performance Contracts (EPCs) are usually quite complex public buildings, sometimes relatively old and usually barely documented from the technical standpoint. Gathering comprehensive and reliable technical information is a time consuming and expensive process that has to be carried out within the submission deadline. In these conditions, the standard approach to energy performance forecasting which uses detailed simulation is practically unfeasible. This paper proposes a reduced-order modeling approach that is tailored to the EPC tendering phase. The proposed methodology extends a third order building model, introducing explicit, albeit still abstract, representations of the heating/cooling system, of the weather influence and of the end-user gains. The extended parameter set reflects to a large degree the information that is readily available in practical on-site surveying, or that can be easily calculated from that information. As a consequence of the simplified physics, a knowledge driven, practical calibration procedure, which provides an effective way of reducing uncertainty, is proposed. The calibration procedure analyses the uncertainty present in the available knowledge and uses the constraints imposed by the implemented physics on the parameters’ dynamic to assess their value estimation. The modeling approach is exemplified through three case studies: the first one provides the comparison of the reduced-order model predictions with the outcomes of a detailed model of a small hospital, the second one is used to compare the reduced-order model predictions with the detailed measurements of energy consumption of a real building, and the third case study exemplifies the use in operational context with scarce information.Peer ReviewedPostprint (author's final draft

Assessing the effectiveness of gamification in reducing domestic energy consumption: Lessons learned from the EnerGAware project

The application of gamification to encourage energy conservation behaviour in house occupants is an emerging field of research. However, empirical evidence of its effectiveness is lacking. This paper presents lessons learnt from the EU-funded EnerGAware research project, in which an innovative serious game (a game designed for purposes other than purely entertainment) was developed to promote reduced energy consumption and carbon emissions by changing social housing tenants’ energy efficiency behaviour. The game was validated in a sample of European social housing using a longitudinal, two-stage experimental design, employing both pre-post and control group approaches. While some aspects of the game did not work as intended, there were nevertheless some positive impacts. The intervention increased social housing tenants’ awareness and engagement in certain energy saving behaviour and provided an average electricity saving of 3.46% and an average gas saving of 7.48%. Although savings were found not to be statistically significant, an effect size was detected (0.2). Therefore, future steps should exploit all available opportunities to replicate the pilot and increase the sample size so as to gain stronger evidence of the game’s impact. Preliminary results support the utility of gaming investment in the household energy efficiency field, and provide useful insights and pathways that could be incorporated into the development of future serious game interventions to foster their effectiveness.Peer ReviewedPostprint (published version

Mobile learning in a Real-World Construction Engineering Scenario

In this paper, we will present a learning scenario dealing with health and safety aspects in construction engineering. The scenario consists of two parts: first, a number of classical classroom sessions dealing with the theory, and second construction sites will be explored to identify and learn more about the health and safety aspects in a real-world context. The real-world scenario will be mediated using mobile devices, which will be used to deliver learning content tailored to specific learning situations. Moreover, students will use mobile devices to create their own learning content; a range of multimedia annotations portraying possible health and safety aspects in real constructions that can be used as a basis for later discussions

A web-based system for sharing and disseminating research results: the underground construction case study

Researchers often have to go to multiple information sources in order to identify high-quality, time-critical information. Due to the dynamic and unstructured nature of research results, they are faced with such problems as distributed sources and inter-disciplinary differences in terminology that prevent them from accessing the information they need. This paper presents the System for Active Knowledge Management (SAKM), a web-based system that addresses these problems by supporting effective information search and analysis, and by enhancing communication and collaboration among researchers. The system was implemented in the underground construction field, which has experienced tremendous growth and is facing increasingly complex and challenging research issues. Preliminary testing suggested that a tool like the SAKM could improve the information transfer of research results. The validation stage confirmed that the system met the requirements of the initially defined scenarios

Knowledge management perceptions in construction and design companies

Knowledge management (KM) has been studied extensively in recent years. Some consider knowledge to be the most strategically important resource for any company, but the fragmented, project-based and task-oriented nature of construction work makes it more difficult to implement KM in this sector. This paper presents a survey of perceptions of KM implementation in the Spanish construction sector and compares the results obtained from design and construction firms. Data were collected from the leading civil engineering companies in Spain. The survey found that the Spanish construction industry is aware of the benefits of KM but that systematic KM is not generally implemented. The findings clearly demonstrate that changes in organizational culture are critical to successful KM. The survey also revealed some distinctions between the KM perception of design firms and that of construction firms

Mitigating construction safety risks using prevention through design

Introduction Research and practice have demonstrated that decisions made prior to work at construction sites can influence construction worker safety. However, it has also been argued that most architects and design engineers possess neither the knowledge of construction safety nor the knowledge of construction processes necessary to effectively perform Construction Hazards Prevention through Design (CHPtD). Method This paper introduces a quantitative methodology that supports designers by providing a way to evaluate the safety-related performance of residential construction designs using a risk analysis–based approach. The methodology compares the overall safety risk level of various construction designs and ranks the significance of the various safety risks of each of these designs. The methodology also compares the absolute importance of a particular safety risk in various construction designs. Results Because the methodology identifies the relevance of each safety risk at a particular site prior to the construction stage, significant risks are highlighted in advance. Thus, a range of measures for mitigating safety risks can then be implemented during on-site construction. Impact on industry The methodology is specially worthwhile for designers, who can compare construction techniques and systems during the design phase and determine the corresponding level of safety risk without their creative talents being restricted. By using this methodology, construction companies can improve their on-site safety performance