Adopting smart architectural design principles is one of the keys to so-called nZEB (Nearly Zero Energy Building) structures, an initiative aimed at contributing to the planet’s sustainability.

Did you know that 40% of the energy consumed in the European Union is used by buildings? An automatic garage door opening, the air conditioner running at full blast to beat the summer heat, the water heater constantly refilling… It’s no secret that “life” inside the home is inconceivable without the energy that powers such everyday functions as indoor climate control and the functionality of living spaces. Hence the urgency in developing nearly zero-energy buildings.

Given that more than a third of CO2 emissions into the atmosphere come from buildings, the fight against climate change inevitably requires a commitment to sustainability in the sector. The commitment to eco-design and smart architectural design is a decision with far-reaching implications for the future, and this is where nZEB (Nearly Zero Energy Building) structures come into their own.

What are nearly zero-energy buildings?

More and more professionals—architects, builders, designers, and others—are embracing sustainable design and green architecture. But the situation calls for a genuine commitment from society as a whole and from an industry that, as we mentioned, is responsible for a significant portion of CO2 emissions into the atmosphere. The energy efficiency of buildings is a key issue in ensuring the planet’s sustainability, and the term “Nearly Zero Energy Building” captures this shared sentiment, which can be applied to the real estate sector.

What are known as nearly zero-energy buildings, or nZEBs, is simply the term used to describe buildings that meet very high energy efficiency standards and have nearly zero energy consumption, or very low energy consumption, the majority of which must come from renewable sources, produced on-site or in the surrounding area.

This is set forth in European Directive 2010/31/EU on the energy performance of buildings. Based on the European standard, since 2020 in the residential sector and since 2018 in the public sector, newly constructed buildings must meet the necessary criteria to be considered nearly zero-energy buildings.

Characteristics of nZEB Buildings

The implementation of the European directive represents a significant boost to energy efficiency in buildings. Essentially, it is the starting point for a shift in the construction model, which now incorporates efficiency and the integration of various types of renewable energy into the design process, thereby reducing both energy consumption and emissions from the buildings themselves. But how can these parameters be applied to transform structures into nearly zero-energy buildings? Some of the key factors are:

Architectural Design

New buildings are adopting what is known as bioclimatic architecture. By taking into account the specific conditions of the surroundings as well as the local climate, this type of architectural design optimizes environmental resources such as sunlight, orientation, and humidity, among others, thereby reducing the environmental impact of the buildings.

Smart Envelope

Along the same lines, nZEB buildings also incorporate passive architecture principles. Thus, it is important to choose carefully among the different types of facades, although the term “smart building envelope” also includes roofs and floors that take advantage of environmental heat sources and sinks (low-emissivity glass, green roofs, thermal mass, ventilated facades, etc.).

Efficiency and High Performance of Facilities

Energy-efficient systems and equipment with high seasonal average performance are another key aspect of low-energy buildings. These types of homes incorporate everything from energy-efficient appliances to mechanical ventilation systems with heat recovery, as well as passive elements for home climate control—all powered by renewable energy sources. The goal? To achieve and maintain acceptable comfort levels with minimal energy consumption.

High-quality construction

Given that factors such as airtightness, rigorous control of thermal bridges, and high-performance insulation are essential in nZEB buildings, it seems logical to conclude that meticulous construction and a commitment to high-quality materials are another of the pillars of this new architecture.

New Technologies

Smart energy demand management rounds out the defining characteristics of nearly zero-energy buildings. In this regard, home automation becomes the best ally. Through these types of systems, it is possible to automate and control a wide range of elements in the home, from lighting to security to climate control.

How to Achieve Nearly Zero-Energy Buildings (nZEB)

Nearly Zero-Energy Buildings in Spain

The implementation of European policy affects all EU countries, and Spain is no exception. New construction projects must comply with the supranational regulatory framework to ensure the planet’s sustainability. It is not just a matter of reducing energy consumption, but of decreasing dependence on energy itself. In other words, the most sustainable energy is the energy that is not used.

In this vein, Culmia is committed to applying energy-saving criteria, as evidenced by its nearly zero-energy homes. The developer has embraced the term “Nearly Zero Energy Building” by constructing, among other projects, Culmia Innova Torrejón—a 92-unit residential building that earned a special mention at the ASPRIMA Awards, a benchmark for public recognition of the best initiatives in the real estate sector.

Its commitment to sustainable design reflects its current and future commitment to society—a responsibility that goes beyond nZEB buildings. The goal is simply to provide users with a better quality of life, and to that end, the application of the most advanced processes, methods, and certifications in the pursuit of energy efficiency is key.