El futuro de las políticas de construcción sostenible. Tendencias y predicciones

Sustainable building policies have followed a progressively more demanding trajectory over the past three decades. The first regulatory generation, represented by directives such as the original EPBD of 2002, focused on reducing operational energy demand through thermal insulation requirements and system performance standards. The second generation, embodied in Directive 2010/31/EU, introduced the concept of the nearly zero-energy building (nZEB), requiring a primary energy demand below 40-60 kWh/m2/year depending on the climate zone. The third generation, inaugurated by the revised EPBD of 2024 (Directive 2024/1275), transcends operational energy to incorporate the global warming potential (GWP) of the building's entire life cycle, including material manufacturing, transport, construction, use, maintenance, and end of life, in accordance with standard EN 15978. France was a pioneer with its Reglementation Environnementale RE2020, in effect since January 2022, which establishes maximum embodied carbon thresholds of 640 kg CO2eq/m2 for single-family dwellings and 740 kg CO2eq/m2 for multi-family buildings, with progressive reductions down to 415 kg CO2eq/m2 by 2031.

The quantitative impact of this regulatory shift is decisive. According to the World Green Building Council (2019), embodied carbon accounts for between 20% and 50% of the total life-cycle emissions of a new high energy-efficiency building, a proportion that grows as the electrical grid decarbonizes and operational consumption decreases. In Sweden, the Climate Declaration Act for buildings (2022) requires the calculation and disclosure of CO2 emissions from the construction phase of all new buildings, and from 2027 it will impose maximum limits of 330 kg CO2eq/m2 for residential buildings. Denmark has applied since 2023 a maximum carbon budget of 12 kg CO2eq/m2/year (over a 50-year life cycle) for new buildings exceeding 1,000 m2, reducible to 7.5 kg CO2eq/m2/year by 2029. The Netherlands has required since 2018 an MPG calculation (Milieu Prestatie Gebouwen) with a maximum of 0.8 EUR/m2/year in monetized environmental impact, set to decrease to 0.5 EUR/m2/year by 2030. Spain still lacks specific embodied carbon regulation, although the Ministry of Transport plans to incorporate carbon footprint indicators in the CTE update scheduled for 2026.

The EU Taxonomy Regulation (2020/852) has introduced a market mechanism that complements and at times surpasses the influence of building codes. For a real estate asset to qualify as environmentally sustainable under the taxonomy, it must meet technical screening criteria that include a primary energy demand in the top 15% of the national stock, equivalent in Spain to an A energy rating with consumption below 45-55 kWh/m2/year depending on the climate zone. Renovated buildings must demonstrate a minimum 30% reduction in primary energy consumption or achieve class A. According to European Banking Authority data (2023), mortgage loans associated with taxonomy-aligned buildings represent only 3.2% of the total in European banking, but this proportion is forecast to reach 15-20% by 2030, driven by Pillar III disclosure requirements and capital penalties for non-aligned assets.

The financial impact is quantifiable. A Deutsche Bank Research study (2023) estimated that taxonomy-aligned buildings obtain mortgage interest rates 20-40 basis points lower than non-aligned ones, which for an average mortgage of 200,000 EUR over 25 years represents savings of 8,000-18,000 EUR. In Madrid's prime office market, CBRE (2024) documented a rental premium of 14-22% for environmentally certified buildings aligned with the taxonomy compared to non-certified buildings. The European Central Bank has noted that 75% of real estate loans granted in the eurozone correspond to buildings with an energy rating of D or lower, exposing banks to a transition risk valued at 200,000-400,000 million EUR in asset depreciation if regulation tightens renovation requirements. This financial pressure makes the taxonomy a potentially more effective renovation driver than building codes, because it directly affects the cost of capital and market value of existing properties.

Sustainable building policy is progressively incorporating the dimension of material circularity. The EU Circular Economy Strategy (2020) and the revised Construction Products Regulation (2024) introduce requirements for recycled content, design for disassembly, and digital product passports. Digital building passports, currently in a pilot phase across 7 European countries through the Building Circularity Passports initiative of the BAMB project, record the material composition, location, assembly conditions, and reuse potential of each component. According to a European Commission study (2023), widespread adoption of digital passports could increase the reuse rate of construction materials from the current 3-5% to 15-20% by 2035, preventing the emission of 80-120 million tonnes of CO2 annually in the EU. The Netherlands leads this trend with the CB'23 program, which establishes measurable circularity indicators (Material Circularity Indicator) and has required a minimum of 10% secondary materials in public buildings since 2023.

In the Spanish regulatory sphere, the Circular Economy Action Plan 2021-2023 (PAEC) included construction as a priority sector, but concrete measures have been limited to updating Royal Decree 105/2008 on construction and demolition waste management, with a new target of 70% recovery by weight of non-hazardous CDW by 2025. The actual CDW recycling rate in Spain stands at 40%, compared to 90% in the Netherlands and 87% in Germany (Eurostat, 2022). The main barrier is the lack of a sufficient network of treatment plants: Spain has 180 authorized plants across its 52 provinces, compared to 2,400 in Germany. The Level(s) framework from the European Commission, published in version 2.0 in 2021, provides 16 standardized sustainability indicators grouped into 6 macro-objectives (GHG emissions, resource efficiency, water, health, adaptation, and life-cycle cost) that will foreseeably form the basis of future regulatory requirements across all Member States.

Projections from the Global Alliance for Buildings and Construction (GlobalABC, 2023) indicate that the building sector must reduce its direct and indirect emissions by 50% before 2030 relative to 2020 to meet the 1.5 degrees C target of the Paris Agreement. This requires building codes in all G20 economies to mandate zero-emission buildings by 2030 (new) and 2050 (renovated existing). Currently, only 14 of the 20 G20 countries have mandatory energy codes for all building types, and only 4 (France, Denmark, Sweden, and the Netherlands) incorporate embodied carbon limits. The most robust normative convergence prediction is the global adoption of Level(s)-type frameworks as a common language: UNEP's Building Energy Codes program forecasts that 30 countries will have adopted life-cycle carbon indicators in their national codes before 2030, up from the current 8.

An emerging trend is the incorporation of climate justice criteria into building policies. The revised EPBD requires Member States to protect vulnerable households through financing programs that cover at least 50% of renovation costs for families in energy poverty, which in Spain affects 6.8 million people according to the National Strategy against Energy Poverty (2019-2024). Next Generation EU funds have allocated 6,820 million EUR to energy retrofit in Spain, with the goal of renovating 510,000 dwellings by 2026, although by the end of 2024 only 78,000 interventions had been completed, 15% of the target. The prediction for the coming decade is that sustainable building policies will be integrated with those for social housing, urban mobility, and public health within holistic regulatory frameworks, moving beyond the current sectoral approach. Simulation models from the Joint Research Centre (JRC, 2024) estimate that the complete decarbonization of the European building stock by 2050 requires a cumulative investment of 3.5 trillion EUR but generates a net positive return of 5.2 trillion EUR in energy savings, healthcare cost reductions, and increased property values.