{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:47:57Z","timestamp":1760150877728,"version":"build-2065373602"},"reference-count":32,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,31]],"date-time":"2022-01-31T00:00:00Z","timestamp":1643587200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Buildings"],"abstract":"<jats:p>Steady-state methods have been widely used in Europe to analyse the energy performance of low-energy buildings. The accuracy of such methods depends on the assumptions regarding the compensation of non-stationary effects, but also on the input design data, such as the temperature of unconditioned spaces (UnSp). This temperature depends mainly on the thermal characteristics of UnSp envelope, air ventilation rate, temperature of the conditioned spaces and the external environment. External environment varies over time, daily and seasonally, making it difficult to accurately estimate UnSp temperature. European Union (EU) directives stated that the UnSp temperature can be evaluated by the adjustment factor (b) set by EN ISO 13789. However, each Member State may adjust procedures, by proposing simplified approaches, either for new or existing buildings. In this paper the b-values measured on-site in three dwellings were compared to those calculated by EN ISO 13789 as well as those estimated based on simplified procedures, allowed in the regulatory framework of some EU Member States, namely Ireland, Portugal, Spain, France and Italy. The study allowed to conclude that EN ISO 13789 and Irish BR 443 provided similar values. However, if the purpose is to simplify procedures and reduce computation effort, French RE2020 proved to be very effective. The thermal characteristics of the UnSp envelope and air ventilation rate were identified as the parameters that most affect the estimation of the b-value, while thermal losses through linear thermal bridges and the ground do not seem to have a significant impact.<\/jats:p>","DOI":"10.3390\/buildings12020146","type":"journal-article","created":{"date-parts":[[2022,1,31]],"date-time":"2022-01-31T08:20:29Z","timestamp":1643617229000},"page":"146","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Comparison between On-Site Measured and Estimated Based Adjustment Factor Values Used to Calculate Heat Losses to Unconditioned Spaces in Dwellings"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3865-490X","authenticated-orcid":false,"given":"Miguel C. S.","family":"Nepomuceno","sequence":"first","affiliation":[{"name":"Department of Civil Engineering and Architecture, University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"},{"name":"C-Made, Centre of Materials and Building Technologies, 6201-001 Covilh\u00e3, Portugal"},{"name":"Lab2PT, Landscape, Heritage and Territory Laboratory, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2591-0137","authenticated-orcid":false,"given":"Ana M. T.","family":"Martins","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering and Architecture, University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"},{"name":"Lab2PT, Landscape, Heritage and Territory Laboratory, 4800-058 Guimar\u00e3es, Portugal"},{"name":"CIDEHUS, Interdisciplinary Centre for History, Culture and Societies, 7000-809 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1028-4655","authenticated-orcid":false,"given":"Hugo A. S.","family":"Pinto","sequence":"additional","affiliation":[{"name":"Department of Civil Engineering and Architecture, University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"},{"name":"C-Made, Centre of Materials and Building Technologies, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,31]]},"reference":[{"key":"ref_1","unstructured":"Guterres, A. (2021, December 03). Secretary-General\u2019s Statement on the Conclusion of the UN Climate Change Conference COP26 on 13 November 2021. Available online: https:\/\/www.un.org\/sg\/en\/node\/260645."},{"key":"ref_2","unstructured":"European Commission (2019). Clean Energy for All Europeans, Publications Office of the European Union."},{"key":"ref_3","unstructured":"International Energy Agency (IEA) (2021, December 15). Energy Performance Certification of Buildings\u2014A Policy Tool to Improve Energy Efficiency. 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Decree No. 48 of 10 June 2020"},{"key":"#cr-split#-ref_28.2","unstructured":"Attuazione Della Direttiva (UE) 2018\/844 del Parlamento Europeo e del Consiglio, del 30 Maggio 2018, Che Modifica la Direttiva 2010\/31\/UE Sulla Prestazione Energetica Nell'edilizia e la Direttiva 2012\/27\/UE Sull'Efficienza Energetica [Im-plementation of Directive (EU) 2018\/844 Amending Directive 2010\/31\/EU on the Energy Performance of Buildings and Directive 2012\/27\/EU on Energy Efficiency], European Union."},{"key":"ref_29","unstructured":"(2017). Thermal bridges in building construction\u2014Linear thermal transmittance\u2014Simplified methods and default values (Standard No. EN ISO 14683:2017)."},{"key":"ref_30","unstructured":"(2017). Thermal bridges in building construction\u2014Heat flows and surface temperatures\u2014Detailed calculations (Standard No. EN ISO 10211:2017)."},{"key":"ref_31","unstructured":"(2017). Thermal performance of buildings\u2014Heat transfer via the ground\u2014Calculation method (Standard No. EN ISO 13370:2017)."}],"container-title":["Buildings"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-5309\/12\/2\/146\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:11:45Z","timestamp":1760134305000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-5309\/12\/2\/146"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,31]]},"references-count":32,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2022,2]]}},"alternative-id":["buildings12020146"],"URL":"https:\/\/doi.org\/10.3390\/buildings12020146","relation":{},"ISSN":["2075-5309"],"issn-type":[{"type":"electronic","value":"2075-5309"}],"subject":[],"published":{"date-parts":[[2022,1,31]]}}}