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Water Damage in Buildings and Associated Microbiological Contamination
Published in Rafał L. Górny, Microbiological Corrosion of Buildings, 2020
Modern construction places emphasis on environmental care through aspects of energy economy. In order for a building to meet the energy efficiency requirement, it must have, among other things, adequate thermal insulation. In a building, heat can escape through walls, roof and floor. However, the most important place where heat escapes from buildings are windows and doors as well as their connection points to the walls [BPIE 2010]. Incorrect installation of windows often leads to the formation of the so-called ‘thermal bridge’ – a part of the building which has much worse thermal insulation than the adjacent part. Thermal bridges have adverse effects, as they lead to heat loss and point or linear cooling of parts of the building envelope. This may be conducive to condensation and dampness, which creates favorable conditions for microbial growth [Gorse and Johnston 2012]. Other consequences of thermal bridges include uncontrolled heat loss, up to 30%, and mechanical damage to the structure. Structural nodes that connect different elements of the building envelope are mostly prone to the occurrence of thermal bridges, and thus microbial growth. Among such places are the connection points between the roof and external wall, as well as between the balcony and ceiling, window frames, ring beams, lintels and cellar walls [Ge et al. 2013; Allen and Lano 2009].
Energy and Environmental Monitoring
Published in Dejan Mumovic, Mat Santamouris, A Handbook of Sustainable Building Design and Engineering, 2018
Alex Summerfield, Hector Altamirano-Medina, Dejan Mumovic
This supplementary research aimed to investigate the relationship of various indoor parameters, such as air tightness of the house and household moisture production, with the development of indoor mould. Ideally the information specifically related to mould should include the following:Physical condition related to the environment where mould is present (building materials, building age, etc).Temperature and RH: hourly measurement of indoor and external conditions. In view of the time required for mould spores to germinate and Mycelium to grow, these parameters should be for at least 4 to 6 months or a complete season.Occupancy behaviour and indoor moisture production via a questionnaire.Visible mould occurrence: a simple index can be used where two or three categorisation levels can be used, (e.g. no visible mould, small spots, hand size patches and large patches).Indoor air quality, ventilation and air tightness.Identification of potential thermal bridges and damp problems via visual inspection and measurement.
Applications
Published in Raj P. Chhabra, CRC Handbook of Thermal Engineering Second Edition, 2017
Joshua D. Ramsey, Ken Bell, Ramesh K. Shah, Bengt Sundén, Zan Wu, Clement Kleinstreuer, Zelin Xu, D. Ian Wilson, Graham T. Polley, John A. Pearce, Kenneth R. Diller, Jonathan W. Valvano, David W. Yarbrough, Moncef Krarti, John Zhai, Jan Kośny, Christian K. Bach, Ian H. Bell, Craig R. Bradshaw, Eckhard A. Groll, Abhinav Krishna, Orkan Kurtulus, Margaret M. Mathison, Bryce Shaffer, Bin Yang, Xinye Zhang, Davide Ziviani, Robert F. Boehm, Anthony F. Mills, Santanu Bandyopadhyay, Shankar Narasimhan, Donald L. Fenton, Raj M. Manglik, Sameer Khandekar, Mario F. Trujillo, Rolf D. Reitz, Milind A. Jog, Prabhat Kumar, K.P. Sandeep, Sanjiv Sinha, Krishna Valavala, Jun Ma, Pradeep Lall, Harold R. Jacobs, Mangesh Chaudhari, Amit Agrawal, Robert J. Moffat, Tadhg O’Donovan, Jungho Kim, S.A. Sherif, Alan T. McDonald, Arturo Pacheco-Vega, Gerardo Diaz, Mihir Sen, K.T. Yang, Martine Rueff, Evelyne Mauret, Pawel Wawrzyniak, Ireneusz Zbicinski, Mariia Sobulska, P.S. Ghoshdastidar, Naveen Tiwari, Rajappa Tadepalli, Raj Ganesh S. Pala, Desh Bandhu Singh, G. N. Tiwari
In general, a thermal bridge is defined as a location within the building envelope or architectural component, which exhibits considerably more heat flow than surrounding areas. Thermal bridging refers to the loss of energy by conduction through elements that “bridge” the insulation of a wall or roof enclosure of a conditioned space. While it is a common knowledge that most structural materials contribute to thermal bridging, it is good to remember that, in reality, thermal shorts occur much more often than just when a conductive element passes through or bypasses a thermal insulation barrier. Considering that in building components with temperature gradients, heat flow has multidimensional character and taking into account the complexity of today’s building envelopes, these thermal pathways often require three-dimensional numerical analysis.
Automated classification of thermal defects in the building envelope using thermal and visible images
Published in Quantitative InfraRed Thermography Journal, 2023
Changmin Kim, Gwanyong Park, Hyangin Jang, Eui-Jong Kim
Various thermal defects cause heat loss in a building envelope. Thermal defects in the building envelope are caused by various factors, such as thermal bridges, air leakages [1–4]. The type and location of thermal defect affects the energy retrofit strategy of the building [5]. For example, thermal bridges, a representative type of thermal defect, are classified as geometrical or material-related thermal bridges according to their causes [6]. Geometrical thermal bridges are caused by a break in insulation due to building shapes, such as at the intersection of external walls and floors. Conversely, material-related thermal bridges are caused by irregularities in the thermal performance between materials. Depending on the cause or degree of thermal bridges, thermal breaks [7] or external thermal insulation systems [8] are applied. Air leakage is caused by unintentional gaps in the building envelope [9]. Accordingly, to reduce air leakage, the application of sealants, gaskets, or additional window panels between gaps, such as between the window and wall, can be considered [10]. Defects related to insulation can be solved by reinforcing the insulation in the relevant area. These defects may occur individually or in combination [11]. Therefore, to establish an appropriate retrofit strategy, it is necessary to first identify the type and location of the thermal defects.
Examining energy efficiency requirements in building energy standards: Implications of sustainable energy consumption
Published in Energy Sources, Part B: Economics, Planning, and Policy, 2022
Junaid Tippu, Subramaniam Saravanasankar, Bathrinath Sankaranarayanan, Syed Mithun Ali, V. G. Venkatesh, Syed Shuibul Qarnain, Muthuvel Sattanathan
The existing lighting and energy-intensive patterns have given rise to an emerging energy crisis that must be addressed urgently (Santamouris et al. 2001). Built-in lighting systems (R6) consume energy for illumination. Between 1997 and 2010, lighting in the residential sector in the EU accounted for approximately 2.5% of the energy. However, after applying energy-efficiency policies, there has been a considerable reduction in lighting energy (Allouhi et al. 2015). As buildings’ heating, cooling, and lighting account for energy consumption, passive energy sources, such as energy should be used for energy efficiency in buildings (Gupta, Tiwari, and Tiwari 2017). Kotti, Teli, and James (2017) proposed several methods to reduce the energy consumption in buildings using thermal bridges (Santamouris et al. 2001). They also introduced several cost-effective models for the heating and cooling of a building. Thermal bridges are passive technologies that have the potential to reduce the energy consumption in buildings.
Effect of the exposed steel structure on the thermal performance of buildings
Published in Architectural Engineering and Design Management, 2022
Lucas Fonseca Caetano, Henor Artur de Souza, Adriano Pinto Gomes
The standard EN ISO 10211 (International Organization for Standardization, 2017) defines a thermal bridge as a part of the building envelope where the otherwise uniform thermal resistance is significantly changed by full (Figure 1 a) or partial (Figure 1 b) penetration of the building envelope by materials with a different thermal conductivity, and/or a change in thickness of the fabric (Figure 1 c), and/or a difference between internal and external areas, such as occur at wall/floor/ceiling junctions (Figure 1 d). This effect in building constructions give rise to changes in heat flow rates compared with those of the unbridged structure, modifying the total heat flow through the surface of the building envelope (International Organization for Standardization, 2015). In this sense, thermal bridges can increase heat loss during winter and heat gains during summer (Evola, Margani, & Marletta, 2011). The additional heating and cooling thermal load caused by these thermal bridges have to be accommodated by mechanical systems, leading to higher energy consumption (Ge, McClung, & Zhang, 2013). The use of multi-layer walls with high thermal resistance values is widely applied to reduce heat losses in buildings during the wintertime. However, it is important to also treat the less resistant components of the envelope such as doors, windows, and all the various thermal bridges, otherwise, efforts to reduce heat losses or gains can be dismissed (Asdrubali, Baldinelli, & Bianchi, 2012).