Comparison of Thermal Bridges Calculate Method through Window Jamb

2013 ◽  
Vol 855 ◽  
pp. 130-133
Author(s):  
Rastislav Ingeli
Keyword(s):  
Heat Conduction ◽  
Thermal Conductance ◽  
Theoretical Background ◽  
Building Envelope ◽  
Building Construction ◽  
Building Envelopes ◽  
Thermal Bridge ◽  
Detailed Specification ◽  
Flow Through ◽  
Thermal Bridges

This paper is focused on comparison of thermal bridges calculate method through window jamb in building envelopes. The present approach is based on an integrated 2D dynamic simulation. The theoretical background of the adopted approach is presented. The reliability of this approach in evaluating thermal bridges as well as its applicability to different geometric shapes is proved. Detailed specification and calculation of each thermal bridge in these buildings should be taken into account. the heat flow through a building construction is considered to be of the onedimensional (1D) type. This is because the thermal conductance and temperature differential in this direction are much greater than that in the lateral directions. The thermal bridge is the part of the building envelope through which heat conduction is multi-dimensional. Therefore, in recent studies, the problem of heat conduction in the building construction has been treated as a multi-dimensional.

scholarly journals A new method to estimate point thermal transmittance based on combined two-dimensional heat flow calculation

2020 ◽  
Vol 172 ◽  
pp. 08005
Author(s):  
Jaanus Hallik ◽  
Targo Kalamees
Keyword(s):  
Heat Flow ◽  
Three Dimensional ◽  
Multiple Linear Regression Model ◽  
Building Envelope ◽  
New Method ◽  
Two Dimensional ◽  
Thermal Transmittance ◽  
Thermal Bridge ◽  
Thermal Bridges ◽  
Third Dimension

A well-insulated, airtight and thermal bridge free building envelope is a key factor for nearly zero energy buildings (nZEB). However, increased insulation thickness and minimized air leakages increase the effect of thermal bridges on overall energy efficiency of the nZEBs. Although several more prominent linear thermal bridges are accounted for in the practice the three-dimensional heat flow through vast array of fixation elements, mounting brackets and other point thermal bridges are usually neglected due to time-consuming model preparation routine, lack of input data as well as high number of different thermal bridges that have to be assessed for a single project. In this study a new method was proposed for predicting three-dimensional heat flow and the point thermal transmittance of thermal bridges caused by full or partial penetration of the building envelope with metal elements with uniform geometry in third dimension based on multiple two-dimensional numerical heat flow calculations. A new parameter (equivalent length of thermal bridge) was defined which incorporates the effect of additional thermal transmittance in third dimension when multiplied by the difference of two thermal coupling coefficients derived for two-dimensional cross section. Multiple linear regression model was fitted on database with 102 cases and verified with separate case of window to wall connection incorporating metal penetration at fixation points. The proposed methodology can be useful in general practice where the design team lacks the skills or software tools for conducting detailed numerical analysis in three dimensions.

scholarly journals Assessment of the reliability of thermal protection of enclosing structures of buildings at the design and operation stages

2018 ◽  
Vol 251 ◽  
pp. 03057
Author(s):  
Galina Shibaeva ◽  
Ekaterina Ibe ◽  
Denis Portnyagin
Keyword(s):  
Thermal Imaging ◽  
Thermal Protection ◽  
Residential Buildings ◽  
Building Envelope ◽  
Design Solution ◽  
Construction Technology ◽  
The Finite Element Method ◽  
Building Envelopes ◽  
Thermal Bridge ◽  
Continental Climate

The article presents recommendations for assessing the heat and energy efficiency of a design solution for a building envelope based on the calculation of energy costs during typical periods of time. The recommendations are based on the analysis of defects in thermal protection of building envelopes during design and construction, by studying design documentation, thermal imaging, calculation and verification of building envelope components. Results of calculation of temperature in hazardous structural sites for the design winter conditions with the help of software that implements the finite element method are presented. In the present paper, the design solutions of the nodes of the walls of residential buildings are considered, where, during thermal imaging, thermal bridge are visible through the external walls. It is shown that the using of multilayer brick walls in the apartment houses in a sharply continental climate is irrational due to the rapid deterioration of the properties of the insulation layer. Also, the thermal protection of buildings is influenced by the design solution defects and violation of construction technology.

Thermal Bridges Minimizing through Window Jamb in Low Energy Buildings

2014 ◽  
Vol 899 ◽  
pp. 66-69 ◽  
Author(s):  
Rastislav Ingeli ◽  
Boris Vavrovič ◽  
Miroslav Čekon ◽  
Lucia Paulovičová
Keyword(s):  
Thermal Protection ◽  
Low Energy ◽  
Building Envelopes ◽  
Thermal Bridge ◽  
Window Systems ◽  
Significant Difference ◽  
Low Energy Buildings ◽  
Window Position ◽  
High Thermal Resistance ◽  
Thermal Bridges

Building envelopes with high thermal resistance are typical for low-energy buildings. Detailed specification and calculation of each thermal bridge in these buildings should be taken into account. This paper is focused on thermal bridges minimizing through typical window systems in building envelopes. The aim of this article is to analyze the window position influence, as regards on thermal performance and to point out the installation modality in accordance with the characterization of the windows performance. This can be done by quantifying the percentage increment of the window jamb thermal transmittance. The calculated results also demonstrate that there is significant difference between results obtained by various available calculation approaches. This can be significant especially in buildings with high thermal protection.

scholarly journals Instantaneous field measurements of thermal bridge parameters in ground floor residential room

2019 ◽  
Vol 112 ◽  
pp. 01016 ◽  
Author(s):  
Martin Ivanov
Keyword(s):  
Energy Demand ◽  
Field Measurements ◽  
Building Design ◽  
Building Envelope ◽  
Ground Floor ◽  
Thermal Bridge ◽  
Significant Temperature ◽  
Thermal Bridges ◽  
Infrared Thermal Images ◽  
Heating Energy Demand

The “thermal bridges” are defined as an isolated building’s areas, where the construction elements have higher thermal conductivity, compared with the rest of the building envelope. Thus, at cold winter conditions, a significant temperature difference may occur between neighbouring solid and air volumes within the construction. Moreover, it has been documented, that the heating energy demand of a building may be increased with more than 30%, due to the existence of thermal bridges and the increased heat losses from the indoors. Consequently, in the recent years, norms and standards have been developed, for avoiding thermal bridges during the building design process. But still, thermal bridges exist in the indoor environment, especially in older buildings, where no energy efficient measures have been applied. That is why, the presented study focuses on instantaneous field measurements of thermal bridge parameters in real existing ground floor residential room. The thermal bridge propagation is analysed relative to the indoor and outdoor air temperature and relative humidity, as well as with infrared thermal images of the affected external walls. The achieved results give valuable information about the generic conditions for thermal bridge existence, without considering the building envelope properties.

scholarly journals A Comparative Study between Jordanian Overall Heat Transfer Coefficient (U-Value) and International Building Codes, With Thermal Bridges Effect Investigation

2021 ◽  
Vol 3 (1) ◽  
pp. p10
Author(s):  
Ammar Alkhalidi ◽  
Suhil Kiwan ◽  
Haya Hamasha
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Energy Demand ◽  
Building Envelope ◽  
Overall Heat Transfer Coefficient ◽  
Thermal Bridge ◽  
U Value ◽  
Thermal Bridges ◽  
Heating Degree Days

Depletion of fossil fuel and the environmental effect associated with the use of it have made the topic of “thermal insulation regulations” a major concern in country Jordan and worldwide. This paper reviews the overall heat transfer coefficient U-value in Jordanian code for the building envelope, which represents how much the building envelope transfer heat to the outside environment. U-value was reviewed with respect to the following factors, heating degree days, the heating load required to achieve thermal comfort. Based on the review a new U-value of 0.65 W/m2.K was proposed and it was found that this value reduces the energy demand almost 50%. Moreover, the thermal bridge effect was investigated and it was found that an obvious increase in the U-value is present when having thermal bridges; this will affect the energy demand, almost 200%.

Influence of Thermal Break Element Applied in Balcony Slab on Internal Surface Temperature

2014 ◽  
Vol 1057 ◽  
pp. 79-86
Author(s):  
Peter Buday ◽  
Rastislav Ingeli ◽  
Miroslav Čekon
Keyword(s):  
Energy Efficient ◽  
Energy Use ◽  
Internal Surface ◽  
Building Envelope ◽  
Cold Climate ◽  
Energy Efficient Buildings ◽  
Thermal Bridge ◽  
Advanced Analysis ◽  
Thermal Bridges ◽  
Energy Efficient Building

Reduction of energy use in buildings is an important measure to achieve climate change mitigation. It is essential to minimize heat losses when designing and building energy efficient buildings. For an energy-efficient building in a cold climate, a large part of the space heating demand is caused by transmission losses through the building envelope. To achieve this, it is necessary to have processed a detailed design of buildings. Thermal bridges have to be eliminated in the design of buildings. Thermal bridges occur as point ones or linear. One of the specific details that create thermal leakage is located in balcony slabs. The balcony is one of the main reasons of the increased heat loss of buildings. The presence of thermal bridge in constructions of balcony envelopes influences the energy consumption, durability of the building envelopes, and also the thermal comfort of occupants. This paper is focused on advanced analysis of thermal performance of thermal break element applied in balcony slab with parametric correlation to the thermal properties of wall building envelope.

scholarly journals Natural Fibre Insulation Materials: Use of Textile and Agri-food Waste in a Circular Economy Perspective

2022 ◽  
Vol 4 (1) ◽  
Author(s):  
Lorenzo Savio ◽  
Roberto Pennacchio ◽  
Alessia Patrucco ◽  
Valentino Manni ◽  
Daniela Bosia
Keyword(s):  
Interior Design ◽  
Natural Fibre ◽  
Building Envelope ◽  
Building Construction ◽  
Fibrous Materials ◽  
Building Envelopes ◽  
Acoustic Insulation ◽  
Wide Range ◽  
Building Market ◽  
The Many

AbstractFibrous materials are among those most used for the thermal and acoustic insulation of building envelopes and are also suitable for a wide range of applications. In building construction, the demand for products with low environmental impact — in line with the Green Deal challenge of the European Community — is growing, but the building market is still mostly oriented towards traditional products, missing the many opportunities for using waste materials from existing industrial production. The paper presents the experimental results of new thermal and acoustic insulation products for building construction and interior design, based on previous experiences of the research group. They are produced entirely using waste sheep’s wool as a “matrix” and other waste fibres as “fillers”. The materials proposed originate from textile and agri-industrial chains in the Piedmont region and have no uses other than waste-to-heat biomass. The panels have characteristics of rigidity, workability, and thermal conductivity that make them suitable for building envelope insulation.

scholarly journals Evaluation of Thermal Bridges Using Online Simulation Software

2020 ◽  
Vol 172 ◽  
pp. 08010
Author(s):  
Ligia Moga ◽  
Ioan Moga
Keyword(s):  
Finite Difference Methods ◽  
Building Envelope ◽  
Simulation Software ◽  
Heat Losses ◽  
Modelling And Simulation ◽  
Zero Energy ◽  
Online Simulation ◽  
Thermal Bridge ◽  
Thermal Bridges ◽  
The Impact

In order to reach nearly Zero Energy Buildings, a thorough design must be given in designing proper junctions, which will overall reduce the impact of the thermal bridges on the thermal performance of the building envelope. It is well-known that a thermal bridge is a weak thermal area of the building envelope through which increased heat losses occur. For the thermal bridges' evaluation, several numerical simulation software exist on the market, but their usage implies knowledge regarding the numerical modelling and simulation using various numerical methods (i.e. finite element method, finite difference methods, and others). Due to time constraint, designers use thermal bridges atlases that provide values for the linear heat transfer coefficient for several types of thermal bridges. Nevertheless, the multitude of existing thermal bridges requires more and more atlases which are not feasible in elaborating, due to time constraints. In order to respond to this demand, the authors developed a software for the modelling and simulation of thermal bridges that can be easily accessed by practitioners. The paper presents the software its components and the way that the user can interact with it.

scholarly journals Heat and moisture transfer in wall-to-floor thermal bridges and its influences on the insulation performance

2021 ◽  
Vol 2069 (1) ◽  
pp. 012216
Author(s):  
Yucong Xue ◽  
Jian Ge ◽  
Yifan Fan
Keyword(s):  
Water Vapour ◽  
Moisture Transfer ◽  
Structural Safety ◽  
Building Envelopes ◽  
Thermal Bridge ◽  
Thermal Bridges ◽  
Heat Transfers ◽  
Heat And Moisture ◽  
Insulation Performance ◽  
Transient Numerical Simulation

Abstract The moisture modifies the characteristics of heat transfer in building envelopes. Multiple factors, including the distinct hygric properties of various material, gravity, etc., affect the moisture content, resulting in a non-uniform distribution of water vapour in different parts of the envelope (e.g. column, beam, the main part of exterior walls). Usually, the more water vapour in a material, the higher the thermal conductivity, resulting in more heat transfers here. Moreover, condensation easily occurs where there is wet, marking such parts have risks both on structural safety and mould growth. The wall-to-floor thermal bridge (WFTB) occupies the largest area among all kinds of thermal bridges that formed by frame structures. In this study, we aimed to quantify the influence on heat loss through WFTB when the moisture transfer in envelopes is considered. The average apparent thermal resistance of WFTB (R TB, ave) was defined to access the insulation performance of WFTB in practical application. The results of transient numerical simulation indicated that when the moisture transfer is considered, the insulation performance of building envelopes decreases significantly, while the adverse effect of WFTB on heat insulation becomes less pronounced. The results indicated that the measures of insulation for WFTB should be reconsidered when the moisture transfer is considered.

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