Through the declaration of new construction, a physical modification of a registered property is recorded, such as the construction of a building. The declaration can be for a completed property or a property under construction, in which case the corresponding certificate of completion of works must be granted. The declaration of new construction is always granted by the registered owner.

For new construction or expansion of previous constructions:

• Proof of ownership of the property.

• ID of the interested parties.

• If a company is involved, powers of attorney or appointment of current administrators.

• Cadastral reference (last property tax receipt).

• Municipal building permit.

• Technical project, indicating the budget for material execution.

• Once granted, a certification from the architect who authored the project must be provided, proving that the description contained in the deed matches the project for which the building permit was obtained.

For existing constructions without a technical project:

• Proof of ownership of the property.

• ID of the interested parties.

• If a company is involved, powers of attorney or appointment of current administrators.

• Cadastral reference (last property tax receipt).

• Description of the building's characteristics.

• Municipal certification of the building's existence and its description, proving that the new construction is not subject to any urban planning disciplinary proceedings by the city council.

• Value assigned to the new construction being declared.