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 Dew point temperature analyses in ground floor residential room with existing thermal bridge

2019 ◽  
Vol 112 ◽  
pp. 01017 ◽  
Author(s):  
Martin Ivanov
Keyword(s):  
Field Measurements ◽  
Building Design ◽  
Energy Performance ◽  
Building Envelope ◽  
Dew Point ◽  
Point Temperature ◽  
Ground Floor ◽  
Dew Point Temperature ◽  
Thermal Bridge ◽  
Infrared Thermal Images

The presented study reveals a dew point temperature analyses in ground floor residential room with existing thermal bridge. The dew point temperature is analysed, based on field measurements of indoor air temperature and relative humidity in the residential room, without organized occupants’ behaviour. Furthermore, the dew point temperature is cross-analysed with existing thermal bridge propagation in one of the outer walls of the room, via infrared thermal images. The results represent a valuable indicator for moisture accumulation over the thermal bridge zone, as well as an indicator for future mold growth and other humidity related problems. In the building design practice, the “thermal bridge” is defined as a distant zone, where construction elements have higher thermal conductivity, compared with the rest of the building envelope. These thermal bridges mostly affect the energy performance of the buildings, because of the higher heat losses from inside towards outside. But even more important, moisture build-up and considerable humidity related problems in the occupied areas are probable, due to the decreased surface temperature over the affected thermal zones.

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%.

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.

Thermal Bridges Minimizing through Typical Details in Low Energy Designing

2014 ◽  
Vol 899 ◽  
pp. 62-65 ◽  
Author(s):  
Rastislav Ingeli ◽  
Boris Vavrovič ◽  
Miroslav Čekon
Keyword(s):  
Energy Efficiency ◽  
Thermal Insulation ◽  
Energy Demand ◽  
Building Energy ◽  
Building Envelope ◽  
Low Energy ◽  
Building Energy Efficiency ◽  
Low Energy Buildings ◽  
Thermal Bridges ◽  
The Impact

Energy demand reduction in buildings is an important measure to achieve climate change mitigation. It is essential to minimize heat losses in designing phase in accordance of building energy efficiency. For building energy efficiency in a mild climate zone, a large part of the heating demand is caused by transmission losses through the building envelope. Building envelopes with high thermal resistance are typical for low-energy buildings in general. In this sense thermal bridges impact increases by using of greater thickness of thermal insulation. This paper is focused on thermal bridges minimizing through typical system details in buildings. The impact of thermal bridges was studied by comparative calculations for a case study of building with different amounts of thermal insulation. The calculated results represent a percentage distribution of heat loss through typical building components in correlation of various thicknesses of their thermal insulations.

Integrating building modelling with future energy systems

2018 ◽  
Vol 39 (2) ◽  
pp. 135-146 ◽  
Author(s):  
David Jenkins
Keyword(s):  
Energy Demand ◽  
Energy Systems ◽  
Building Design ◽  
Building Envelope ◽  
Low Carbon ◽  
Industry Practice ◽  
Carbon Performance ◽  
Tools And Techniques ◽  
Integration Project ◽  
The Impact

The low-carbon building design process for a building engineer is often confined to construction, building services and occupancy. However, as we see coincident changes in climate, technologies, fuels and operation, it becomes important to extend this understanding to include wider energy systems, while clarifying the importance of the built environment within that system. With energy systems, such as the National Grid, involving multiple actors from different disciplines, a key challenge is to provide guidance and future projections that are translated into different discipline-specific vernaculars, but with a genesis of common assumptions. More generally, integration across the disciplines must be reflected by modelling approaches, policy-making frameworks and outputs. This article will demonstrate the initial stages of the energy demand research of the Centre of Energy Systems Integration project, where novel modelling techniques are being used to explore the effect of future buildings on national energy systems. Practical application: The tools and techniques described within this article are designed with future industry practice in mind. The driver is the increased importance of external factors outside the traditional building envelope in determining the energy and carbon performance of a building (or buildings). Building engineers, and others within building design teams, require a new portfolio of tools and resources to better account for the impact of buildings on wider energy systems and vice versa. The role of such practitioners is therefore likely to evolve.

scholarly journals PCSP’s Diagonal Tie Connectors Thermal Bridges Impact on Energy Performance and Operational Cost: Case Study of a High-Rise Residential Building in Estonia

2020 ◽  
Vol 172 ◽  
pp. 08006
Author(s):  
Martin Kiil ◽  
Martin-Sven Käärid ◽  
Paul Klõšeiko ◽  
Karl-Villem Võsa ◽  
Raimo Simson ◽  
...  
Keyword(s):  
Energy Demand ◽  
Residential Building ◽  
Energy Performance ◽  
Relative Increase ◽  
Dynamic Simulations ◽  
Climatic Regions ◽  
High Rise ◽  
Thermal Bridge ◽  
Heating Energy Demand ◽  
Air Circulation

This study analyses the effect of air circulation around diagonal tie connectors in precast sandwich panels on heating energy demand, energy performance value and heating costs of a sample residential building. Dynamic simulations were performed using 4 different climatic boundary conditions: Estonian test reference year, Estonian 48-year weather dataset as well as data from Eastern Germany and Northern Finland. The results show that the effect of the thermal bridge is most noticeable in total room heating energy demand (increase of 10.3%), while the influence on energy performance value was 1.1%. The relative increase of total room heating energy demand was similar (7.0-10.3%) in all studied climatic regions.

scholarly journals Air leakage paths in buildings: Typical locations and implications for the air change rate

2020 ◽  
Vol 172 ◽  
pp. 05010
Author(s):  
Lars Gullbrekken ◽  
Nora Schjøth Bunkholt ◽  
Stig Geving ◽  
Petra Rüther
Keyword(s):  
Energy Demand ◽  
Field Measurements ◽  
Building Envelope ◽  
Air Leakage ◽  
Literature Study ◽  
External Wall ◽  
Air Change Rate ◽  
Laboratory Investigations ◽  
High Standards ◽  
Energy Efficient Building

The harsh Norwegian climate requires buildings designed to high standards. An airtight building envelope is crucial to achieve an energy efficient building and to avoid moisture problems. Results from the SINTEF Building defects archive show that a considerable part of the building defects is related to air leakages. In addition, air leakages increase the energy demand of buildings. A literature study has been conducted in order to map typical air leakage paths of Norwegian wooden houses. In order to increase the performance, different sealing methods including the use of tape has been reviewed. The results show that the most common air leakages reported from field measurements in the literature are in the connections between external wall and ceiling or floor, external wall and window or door, and external wall and penetrations in the barrier layers. Results from laboratory investigations showed that the traditional solutions can be further improved by introduction of modern foil materials in combination with sealing tapes. However, questions can be raised regarding the necessity of tape sealing all available joints.

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.

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 Managing climate-change-induced overheating in non-residential buildings

2020 ◽  
Vol 172 ◽  
pp. 02009
Author(s):  
André Badura ◽  
Birgit Mueller ◽  
Ivo Martinac
Keyword(s):  
Energy Demand ◽  
Energy Use ◽  
Residential Buildings ◽  
Climate Extremes ◽  
Building Design ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Indoor Climate ◽  
Climate Conditions ◽  
Outdoor Climate

Large and rapid climatic changes can be uncomfortable and sometimes hazardous to humans. Buildings protect people from external climatic conditions, and also mitigate the impacts of external climate extremes through their design and construction, as well as with the help of dedicated building service and other technical systems. Active space conditioning accounts for more than 30 per cent of the overall final energy use in Germany. In the life cycle of a building, the construction phase (planning and construction) is the phase with the shortest duration. However, the quality applied during this phase has a significant impact on the resources required, as well as the overall building performance during the much longer operational phase. Once built, buildings are often unable to adapt to boundary conditions that were not considered in the original building design. Consequently, changing outdoor climate conditions can result in an uncomfortable indoor climate over the lifetime of a building. The aim of this study was to determine the effectiveness of flexible solutions for reducing winter heating loads and to reducing/avoiding summer cooling loads in nonresidential buildings in Germany. Various external shading scenarios for non-residential buildings were analysed using the IDA ICE indoor climate and energy simulation tool. Key simulation parameters included the orientation and location of the building, as well as the envelope structure. We investigated the impacts of solar shading on heat storage in the building mass and indoor climate and how different types of envelopes affect overall energy use. The result shows that the use of an adaptive building envelope allows a higher reduction of the total energy demand by 7 % to 15 % compared to an increase in insulation thickness only.

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