@article{MalzKrenkelSteffens, author = {Malz, Sebastian and Krenkel, Walter and Steffens, Oliver}, title = {Infrared Reflective Wall Paint in Buildings: Energy Saving Potentials and Thermal Comfort}, series = {Energy and Buildings}, volume = {224}, journal = {Energy and Buildings}, number = {October}, publisher = {Elsevier}, issn = {0378-7788}, doi = {10.1016/j.enbuild.2020.110212}, abstract = {The reduction of the energy demand of existing buildings is the main objective of building refurbishment. Managing the heat radiation properties of the wall construction is a possible way to develop highly effective and resource efficient insulation materials and concepts. The application of infrared reflective wall paints and coatings has been studied since the latter half of the 20th century. A brief review of the literature gives an account of the current research status. One has to realise that the conclusions are not uniformly consistent but depend strongly on the specific boundary conditions and investigated parameters. The study presented here discusses the usage of infrared reflective wall paint in conjunction with heat insulation for historic brick masonry. The possible energy savings are linked to the resulting thermal comfort. We identify critical parameters that must be taken into account when using infrared reflective wall paint and derive recommended design rules for the refurbishment of such building types. The findings prove that infrared reflective wall paint can decrease heat losses by 18\% and up to 22\% if comfort conditions are considered. Increasing energy savings can also cause the negative effect of high radiative asymmetry. Thus, each configuration must be observed in detail.}, language = {en} } @inproceedings{MalzSteffensKrenkel, author = {Malz, Sebastian and Steffens, Oliver and Krenkel, Walter}, title = {Solaraktive Fassaden im Bestandsbau}, series = {Bauphysiktage 2019 in Weimar - Bauphysik in Forschung und Praxis, 25. und 26. September 2019, Bauhaus-Universit{\"a}t Weimar}, booktitle = {Bauphysiktage 2019 in Weimar - Bauphysik in Forschung und Praxis, 25. und 26. September 2019, Bauhaus-Universit{\"a}t Weimar}, editor = {V{\"o}lker, Conrad and Kornadt, Oliver and Jentsch, Mark and Vogel, Albert}, isbn = {978-3-00-063821-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-20464}, pages = {127 -- 129}, abstract = {Im Rahmen des Forschungsprojektes MAGGIE, das am Beispiel des historischen Quartiers Margaretenau in Regensburg innovative L{\"o}sungen f{\"u}r modernes und bezahlbares Wohnen erforscht, soll {\"u}ber eine solaraktive Fassade Sonnenw{\"a}rme im Bestandsmauerwerk eingespeichert werden, um so den Energiebedarf des Geb{\"a}udes zu reduzieren.}, language = {de} } @article{MalzSteiningerDawoudetal., author = {Malz, Sebastian and Steininger, Peter and Dawoud, Belal and Krenkel, Walter and Steffens, Oliver}, title = {On the Development of a Building Insulation using Air Layers with Highly Reflective Interfaces}, series = {Energy and Buildings}, journal = {Energy and Buildings}, number = {236, April}, publisher = {Elsevier}, doi = {10.1016/j.enbuild.2021.110779}, abstract = {In this work, a novel building insulation system implying wooden fiberboards and intermediate air layers with highly reflective interfaces for the reflection of longwave IR radiation is introduced. A wall test sample with a double air insulation layer has been built and experimentally investigated in a dedicated setup, which consists of a differential climatic chamber to simulate different indoor and outdoor conditions. The test results have been utilized in validating the developed simulation model. In addition, a thorough numerical parameter study has been conducted, through which the general design rules of the introduced insulation system for realizing the lowest possible effective thermal conductivity have been defined. Furthermore, a multi-air-layer-insulation concept is developed, and the energy saving potential is evaluated. It turned out that, emissivity, object size and air layer thickness are the most dominant design parameters which influence the thermal conductivity of the introduced insulation. A thermal conductivity of 0.033 W/(mK) has been estimated for a multi-air-layer insulation with 7 layers. The obtained results prove the high insulation potential of the introduced building insulation system compared with insulating materials available in the market while outlining their limitations.}, language = {en} }