{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T02:12:53Z","timestamp":1776737573058,"version":"3.51.2"},"reference-count":16,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T00:00:00Z","timestamp":1771286400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Government MUR","award":["2022TZ3S4M\u2014PRIN 2022"],"award-info":[{"award-number":["2022TZ3S4M\u2014PRIN 2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Thermo"],"abstract":"<jats:p>The integration of Foamed Concrete (FC) into 3D Concrete Printing (3DCP) processes facilitates the design of energy-efficient building envelopes. However, strategies for optimizing material porosity and printing topology to balance winter and summer performance remain underexplored. This study presents a 2D numerical thermal analysis of an innovative 3D-printed building envelope block characterized by sinusoidal internal partitions. Through a parametric variation in porosity (ranging from 10% to 50%) and internal geometry (amplitude and period of the partitions), 45 distinct configurations were simulated. Performance was evaluated by calculating the steady-state thermal transmittance (U) and the periodic thermal transmittance (Yie) under dynamic climatic conditions. The results demonstrate that porosity is the governing parameter; increasing porosity from 10% to 50% reduces U by 31% and, contrary to traditional assumptions for massive structures, also improves Yie by 12.3%. These outcomes are physically driven by the drastic reduction in thermal conductivity, which overcompensates for the loss of thermal mass, leading to a net reduction in overall thermal diffusivity. While internal topology plays a secondary role, its optimization allows for fine-tuning dynamic damping without compromising insulation. The study confirms that 3D printing with foamed concrete enables the overcoming of the traditional trade-off between insulation and thermal inertia. High-porosity configurations (50%) with optimized internal topology emerge as the most effective solution, simultaneously guaranteeing beneficial steady-state and dynamic thermal performance for sustainable buildings.<\/jats:p>","DOI":"10.3390\/thermo6010013","type":"journal-article","created":{"date-parts":[[2026,2,17]],"date-time":"2026-02-17T09:22:46Z","timestamp":1771320166000},"page":"13","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Preliminary Optimization of Steady-State and Dynamic Thermal Performance of 3D Printed Foamed Concrete"],"prefix":"10.3390","volume":"6","author":[{"given":"Fabio","family":"Iozzino","sequence":"first","affiliation":[{"name":"Department of Management, Information and Production Engineering, Universit\u00e0 di Bergamo, Via G. Marconi 5, 24044 Dalmine, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0284-8588","authenticated-orcid":false,"given":"Andrea","family":"Fragnito","sequence":"additional","affiliation":[{"name":"Department of Industrial Engineering, Universit\u00e0 degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3521-1532","authenticated-orcid":false,"given":"Gerardo","family":"Mauro","sequence":"additional","affiliation":[{"name":"Department of Architecture, Universit\u00e0 degli Studi di Napoli Federico II, Via Forno Vecchio 36, 80134 Napoli, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4423-8147","authenticated-orcid":false,"given":"Carlo","family":"Roselli","sequence":"additional","affiliation":[{"name":"Department of Engineering, Universit\u00e0 degli Studi del Sannio, Piazza Roma 21, 82100 Benevento, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,17]]},"reference":[{"key":"ref_1","first-page":"103333","article-title":"Modelling of 3D concrete printing process: A perspective on material and structural simulations","volume":"61","author":"Li","year":"2023","journal-title":"Addit. 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