The date fixes the suspension of the guarantee period. The wording fixes what can still be argued about two years later.
Element 01
Each defect as a discrete, located item
Stated in physical terms, with its position in the property. A list of items survives scrutiny. A characterisation of quality does not.
Water ingress at the junction of the terrace slab and the north wall, second bedroom
Damp problems throughout the apartment
Element 02
Dated photographic evidence
Taken per item and retained with the file, not only attached to the message. Site conditions change, other trades work over the same junctions, and the record is what fixes the delivery condition.
Per-item images, dated, filed with the notice
A general set of photographs sent once
Element 03
An explicit statement of what it is
The communication names itself as a denúncia of non-conformities under Decreto-Lei n.º 84/2021, so it cannot later be characterised as a courtesy note or a snag reminder.
Names the diploma and the purpose in the opening line
A follow-up email to the site manager
Element 04
A requested remedy and a deadline
The diploma sets no hierarchy of remedies for immovable property, so repair, a proportional price reduction, or termination in serious cases are all open. Naming the remedy keeps the later position consistent.
States the remedy sought and a date for response
Asks the developer to look into it
Delivery method, and the one piece of paper to keep
Portuguese practice is a registered letter with acknowledgment of receipt, the carta registada com aviso de receção. An email carrying delivery and read confirmation is defensible, and the registered letter removes the argument entirely. Keep the acknowledgment slip. The date on it is what suspends the guarantee period, and it is the one document the developer cannot dispute.