THERMAL SCIENCE

International Scientific Journal

Jolanta Šadauskienė

,

Juozas Ramanauskas

,

Algimantas Vasylius

IMPACT OF POINT THERMAL BRIDGES ON THERMAL PROPERTIES OF BUILDING ENVELOPES

ABSTRACT
During the design of energy-efficient buildings with a ventilated façade systems, the evaluation of point thermal transmittance is complicated. It requires additional theoretical knowledge, special software and skills to use it. Because of that, point thermal transmittance is often ignored in practice. The dependence of point thermal transmittance, which is appearing because of aluminum fixing elements used in the insulated wall with ventilated façade system, from the thermal and geometrical properties of construction layers are analyzed in this paper. Research has shown, that thermal properties of the supporting wall, where fixing element is located, had the biggest influence on the point thermal transmittance. When thermal conductivity of the supporting wall was increasing, as well as a thickness of the insulation layer, a value of thermal bridge was increasing in a non-linear way. For this reason, the thermal transmittance coefficient of all construction could increase up to 35%. When the thickness of the supporting wall and thermal conductivity of the insulation layer was increased, the value of point thermal bridge was decreasing. The tests revealed strong dependency of the point thermal bridge on the thermal conductivity of bearing layer material and the thickness of the bearing layer of wall. For this reason, thermal bridges should receive greater consideration. It is not enough to use the diagrams of typical fasteners that very often do not take into account the exact thickness and thermal characteristics of materials
KEYWORDS
thermal bridge, point thermal transmittance, energy efficiency, ventilated facade systems
PAPER SUBMITTED: 2018-07-19
PAPER REVISED: 2019-07-15
PAPER ACCEPTED: 2019-07-24
PUBLISHED ONLINE: 2019-08-10
DOI REFERENCE: https://doi.org/10.2298/TSCI180719299S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2020, VOLUME 24, ISSUE Issue 3, PAGES [2181 - 2188]
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Impact of point thermal bridges on thermal properties of building envelopes

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence