Short answer. Yes, within strict limits. Article 669 lets the owner of a wall that is not a party wall, adjoining another's land, make openings to admit light - placed at the height of the ceiling joists or immediately under the ceiling, thirty centimetres square, and fitted in every case with an iron grating imbedded in the wall and a wire screen.
What the law says
the owner of a wall which is not party wall, adjoining a tenement or piece of land belonging to another, can make in it openings to admit light at the height of the ceiling joints or immediately under the ceiling, and of the size of thirty centimeters square, and, in every case, with an iron grating imbedded in the wall and with a wire screen
Civil Code, Article 669 — Restricted Openings For Light. Read the full provision →
What the law says
the owner of the tenement or property adjoining the wall in which the openings are made can close them should he acquire part-ownership thereof
Civil Code, Article 669 — Restricted Openings For Light. Read the full provision →
The restricted opening the law allows
Article 669 gives a narrow permission. Where the distances required for ordinary windows and views are not observed, the owner of a wall which is not party wall, adjoining a tenement or piece of land belonging to another, can make in it openings to admit light at the height of the ceiling joints or immediately under the ceiling, and of the size of thirty centimeters square, and, in every case, with an iron grating imbedded in the wall and with a wire screen. Every element is a requirement: high placement near the ceiling, the fixed small size, and both the iron grating and the wire screen. Miss any of them and the opening is not the one the article sanctions.
Why the opening must be so limited
The design is deliberate. Placed high under the ceiling and only thirty centimetres square, the opening lets in light but not a usable view onto the neighbour's property, and the grating and screen stop it from becoming a passage or a window in disguise. This is the trade-off the law strikes: your wall may have light where the full distances for windows cannot be met, but not at the cost of overlooking your neighbour. An opening that is larger, lower, or unscreened crosses from a mere light-hole into the kind of view the separate distance rules forbid.
Your neighbour can still close or obstruct it
The permission is not a permanent right against the neighbour. The article makes that plain: the owner of the tenement or property adjoining the wall in which the openings are made can close them should he acquire part-ownership thereof, absent a contrary stipulation. He may also obstruct them by building on his own land, or by raising a wall against yours — unless an easement of light has been acquired. So the light you gain is precarious. Unless you have actually acquired an easement of light, your neighbour remains free to block the openings by developing his side, and the light may be lost.
What this does not grant
This is a tolerance for light, not a licence for windows or views. It does not let you open a full window facing the neighbour without the distances the law requires, and mere non-observance of those distances gives you no easement by lapse of time — that kind of encroachment does not ripen into a right through prescription. Nor does the article apply to a true party wall, which is governed by the rules on common walls. And because the neighbour can obstruct the openings by building, this provision secures you nothing against his lawful use of his own land unless a proper easement of light exists.