Replacing windows: do you need a permit in Portugal?

Independent site: we are not a public authority, and this is not legal or tax advice.

Replacing window frames is exempt if the new ones improve energy efficiency, keep the same geometry and proportions, and look the same from outside. This also holds in the protection zone of a listed building, but not for a listed building itself.

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Answer

Exempt if the conditions are met

Conditions

Better energy efficiency, same geometry and volume relation of the frame parts, and an outside finish identical to the original

Protection zones

The exemption applies even in the protection zone of a listed or proposed-listed building (art 6-A(1)(j))

Listed buildings

Not exempt in a listed building, or in a listed group or site (art 6-A(2))

Different design

Changing doors and windows counts as an alteration (art 2(d)), which needs a licence unless art 4 allows prior communication

Before you start

Tell the council at least 5 days before work begins, even for exempt work (art 80-A).

Council rules

Your council can add detail in its own building regulation where the law lets it, so ask before you start.

Legal basis

RJUE art 6-A(1)(j) and 2(d), RJUE (Decreto-Lei 555/99) as republished in the Annex of Decreto-Lei 108/2026

Sources

data.dre.pt/eli/dec-lei/108/2026/05/29/p/dre/pt/pdf

Checked

2026-11-05