A practical guide for developers, architects and clients

The Technical Building Code (CTE) is the basic standard that regulates the requirements that buildings in Spain must meet. Each update has a direct impact on how properties are designed, built and renovated. In recent years, especially since the modification of the Basic Energy Saving Document (DB HE), significant changes have been introduced that affect developers, technicians… and clients.

At Altamira Constructora, we summarise the key points so that you know how these standards affect your construction project.

What is the CTE and why is it so important?

The CTE establishes the minimum conditions that buildings must meet in areas such as:

  • Structural and fire safety
  • Health and accessibility
  • Energy consumption
  • Sustainability and efficiency

Compliance is not only mandatory by law, but also a seal of quality that guarantees comfort, safety and efficiency in any building.

Main new features of the CTE in force (2024-2025)

Higher energy requirements

  • New constructions must approach the Nearly Zero Energy Building (nZEB) standard.
  • Requirements for thermal insulation, air infiltration and transmittance in building envelopes are increased.

Mandatory renewable energies

  • New homes must incorporate solar thermal or photovoltaic energy, depending on the type of use.
  • The pre-installation of charging points for electric vehicles is also valued

More controlled ventilation

  • Improvements in mechanical ventilation systems and indoor air quality control.
  • Special attention to cross ventilation and heat recovery.

Protection against radon gas

  • In specific geographical areas, the incorporation of construction solutions that reduce the entry of this harmful natural gas is required.

How do these changes affect your project?

Whether you are a developer or planning your home, it is essential to:

  • Take the new requirements into account from the outset to avoid cost overruns or last-minute modifications.
  • Have an up-to-date technical team that is familiar with the regulations and applies them from the project phase onwards.
  • View investment in efficiency not as an expense, but as a long-term improvement in comfort, health and energy savings.

Our experience at Altamira Constructora

At Altamira Constructora, we have been applying the CTE improvements to our projects for years. We work in coordination with architects, engineers and developers to:

  • Design from the outset with the correct technical criteria
  • Apply efficient, economical and safe construction solutions
  • Advise the end customer on what really matters: the result

In addition, we keep up to date with every update to the CTE to guarantee the legality, sustainability and quality of every project we carry out.

The Technical Building Code is not just a technical document: it is the basis for better construction.
In 2025, more than ever, understanding and correctly applying its regulations is essential to avoid problems, improve energy performance and ensure buildings are ready for the future.

At Altamira Constructora, we are clear about one thing: building with criteria means building with quality.