{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T00:19:47Z","timestamp":1777421987838,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,21]],"date-time":"2021-10-21T00:00:00Z","timestamp":1634774400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"POCI and FEDER","award":["POCI-01-0145-FEDER-032061"],"award-info":[{"award-number":["POCI-01-0145-FEDER-032061"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>The reduction of unwanted heat losses across the buildings\u2019 envelope is very relevant to increase energy efficiency and achieve the decarbonization goals for the building stock. Two major heat transfer mechanisms across the building envelope are conduction and radiation, being this last one very important whenever there is an air cavity. In this work, the use of aerogel thermal break (TB) strips and aluminium reflective (AR) foils are experimentally assessed to evaluate the thermal performance improvement of double-pane lightweight steel-framed (LSF) walls. The face-to-face thermal resistances were measured under laboratory-controlled conditions for sixteen LSF wall configurations. The reliability of the measurements was double-checked making use of a homogeneous XPS single panel, as well as several non-homogeneous double-pane LSF walls. The measurements allowed us to conclude that the effectiveness of the AR foil is greater than the aerogel TB strips. In fact, using an AR foil inside the air cavity of double-pane LSF walls is much more effective than using aerogel TB strips along the steel flange, since only one AR foil (inner or outer) provides a similar thermal resistance increase than two aerogel TB strips, i.e., around +0.47 m2\u2219K\/W (+19%). However, the use of two AR foils, instead of a single one, is not effective, since the relative thermal resistance increase is only about +0.04 m2\u2219K\/W (+2%).<\/jats:p>","DOI":"10.3390\/en14216927","type":"journal-article","created":{"date-parts":[[2021,10,21]],"date-time":"2021-10-21T16:31:39Z","timestamp":1634833899000},"page":"6927","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Thermal Performance Improvement of Double-Pane Lightweight Steel Framed Walls Using Thermal Break Strips and Reflective Foils"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0134-6762","authenticated-orcid":false,"given":"Paulo","family":"Santos","sequence":"first","affiliation":[{"name":"ISISE, Department of Civil Engineering, University of Coimbra, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9565-6648","authenticated-orcid":false,"given":"Telmo","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"ISISE, Department of Civil Engineering, University of Coimbra, 3030-788 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,21]]},"reference":[{"key":"#cr-split#-ref_1.1","unstructured":"European Union (2018). Directive"},{"key":"#cr-split#-ref_1.2","unstructured":"(EU) 2018\/844 of the European Parliament and of the Council of 30 May 2018 Amending Directive 2010\/31\/EU on the energy performance of buildings and Directive 2012\/27\/EU on energy efficiency. Off. J. Eur. Union, 2018, 75-91."},{"key":"ref_2","unstructured":"Climate Action Network (CAN) Europe (2021). How to Roll out the Energy Transition in Buildings. Factsheet, Available online: https:\/\/caneurope.org\/energy_transition_buildings_factsheet\/."},{"key":"#cr-split#-ref_3.1","unstructured":"European Union (2018). Directive"},{"key":"#cr-split#-ref_3.2","unstructured":"(EU) 2018\/2001 of the European Parliament and of the Council on the promotion of the use of energy from renewable sources. Off. J. Eur. Union, 328, 82-209. European Parliament."},{"key":"ref_4","unstructured":"Santos, P., Sim\u00f5es da Silva, L., and Ungureanu, V. (2012). 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