The 2030 climate and energy framework includes EU-wide targets and policy objectives for the period 2021–2030 of (1) at least 55% cuts in greenhouse gas emissions (from 1990 levels); (2) at least 32% share for renewable energy; and (3) at least 32.5% improvement in energy efficiency. In this context, the methodology of the cost-optimal level from the life-cycle cost approach has been applied to calculate the cost of renovating the existing building stock in Europe. The aim of this research is to analyze a pilot building using the cost-optimal methodology to determine the renovation measures that lead to the lowest life-cycle cost during the estimated economic life of the building. The case under study is an apartment building located in a mild Mediterranean climate (Castellon, SP). A package of 12 optimal solutions has been obtained to show the importance of the choice of the elements and systems for renovating building envelopes and how energy and economic aspects influence this choice. Simulations have shown that these packages of optimal solutions (different configurations for the building envelope, thermal bridges, airtightness and ventilation, and domestic hot water production systems) can provide savings in the primary energy consumption of up to 60%.

Successful design and construction processes aiming towards nearly zero energy building (nZEB) standards are a challenge for the whole construction industry in Europe. Realizing nZEB buildings requires innovative design processes, and technologies based on an integrated design approach facilitated by multidisciplinary work teams. The collaboration between architects, engineers, technical experts and building managers, is essential. Therefore, it is necessary to identify the specific involvement of each profession in order to develop mutual understanding of each others’ disciplines. Additionally, it is vital to provide professionals with the skills needed to achieve optimal nZEB construction and retrofitting in terms of quality, energy efficiency and cost effectiveness. However, this approach is not yet common, as the building sector is still very fragmented. The EU-funded H2020 project PROF/TRAC aims to tackle this issue by developing an Open Training Platform and a methodology for fast and valid co-creation of interdisciplinary qualification schemes for task-based Continuous Professional Development (CPD) for all professions involved. A common methodology for the mapping of skills and qualifications in the form of an Excel tool was developed as a basis, together with a guidance document. This paper presents the skill-mapping methodology, the use of its results to develop national roadmaps, and the BUILD UP Skills advisor app.

Improving energy efficiency in buildings has a key role to play in achieving the ambitious goal of EU-wide climate neutrality by 2050, set out in the European Green Deal. This paper describes a cost-optimal analysis of residential buildings of Valencian Community, Spain. Thus, an assessment of the contribution of total primary energy savings per year (MW/h) of the social dwellings managed by EVha, Entitat Valenciana d’Habitatge i Sòl (eng. Valencian entity for dwelling and ground) towards the national contribution is presented in this paper. To assess it, the MedZEB cost-optimal methodology has been applied to optimise the performance of the building’s envelope. This means that Optimal Renovation Strategies through Life-Cycle Analysis have been applied to obtain the Packages of Optimal Solutions of the different reference buildings in a reference climate. First, the renovation scenario with 100% of the building stock being renovated has been calculated. Then, the renovation scenario of 1%, being the current European rate of renovation and, finally the renovation scenario of 2%, given that the objective of the Renovation Wave is to at least double the annual energy renovation rate of residential and non-residential buildings by 2030 and to foster deep energy renovations.

La cooperación internacional es un componente intrínseco de los procesos de innovación y desarrollo. Además de un modelo de cooperación, las redes constituyen un modelo organizativo para el fortalecimiento institucional, para la articulación de los sistemas nacionales de innovación y para la internacionalización de los mismos. Asimismo, durante los 10 últimos años ha habido un incremento de Living Labs en Europa, vinculados a la innovación, que están formando una creciente comunidad canalizada a través de La Red Europea de Living Labs. Con el objetivo de conocer el estado del arte y las necesidades futuras de las redes de Living Labs se han analizado las redes existentes, siendo el objetivo principal el intercambio de mejores prácticas y lecciones aprendidas. La armonización y la integración de herramientas y métodos entre los socios es otro de los objetivos de cooperación. Finalmente, un tercer objetivo es que entre los socios de los diferentes laboratorios se desarrolle una investigación a mayor escala. Se requiere una mayor estructura organizativa para resultados colaborativos y de investigación a mayor escala, las redes son aún jóvenes.

Sustainable renovation of existing residential building stocks is essential to reduce greenhouse gas emissions, improve energy performance, and support long-term climate-neutral housing strategies. However, decisions based only on operational indicators may overlook important product-stage embodied impacts, especially in highly integrated renovation solutions. This study evaluates how alternative renovation pathways for a public residential building portfolio in the Comunitat Valenciana (Spain) perform from a stock-level sustainability perspective, comparing five INFINITE industrialised retrofit kits (Kit 1–Kit 5) with five paired conventional renovation scenarios (S1–S5). A bottom-up building stock modelling workflow is applied, combining building-energy simulation to quantify operational performance and emissions (B6) with a screening life-cycle assessment of product-stage embodied carbon reported as GWP (A1–A3). To relate upfront and in-use impacts, the study computes carbon payback, cumulative emissions avoided, and a horizon-based partial life-cycle climate indicator, PLC(H), assessed for 2030, 2035, and 2050. The results show a clear sustainability trade-off: renovation packages that sharply reduce operational emissions often require higher upfront embodied carbon, shifting net climate benefits towards longer time horizons. Low-embodied options provide earlier benefits, with Kit 1 reducing PLC(H) by 15.5% by 2030, whereas deeper decarbonisation packages achieve stronger long-term outcomes, with S5 reducing PLC(H) by 70.7% by 2050. A bounded electricity-decarbonisation sensitivity further shows that these long-horizon rankings are affected by lower grid-emission factors, particularly for highly electrified pathways, although the strongest 2050 pathways remain robust across the tested cases. Overall, the findings show that sustainable stock-level renovation planning should jointly consider operational and embodied carbon, carbon payback, and milestone-based cumulative impacts in order to support balanced portfolio sequencing between broadly deployable fast-payback measures and selective deep retrofits.

Unlike other interventions for the improvement of energy efficiency, in the case of the application of prefabricated elements in deep renovations, there is a certain lack of knowledge on the part of potential clients or even technical staff. This article arises from this need, and its objective and main result is the development and presentation of a tool to help in making decisions on whether the industrialized building envelope kits in general and those of the H2020 INFINITE project are applicable in each specific case.