Short answer. No. The law lets a co-owner dodge repair costs by giving up his share of a party wall, but it draws one hard exception: if the wall actually supports a building of his own, he cannot renounce his way out of paying his proportionate share of the repair and maintenance cost.
What the law says
any owner may exempt himself from contributing to this charge by renouncing his part-ownership, except when the party wall supports a building belonging to him
Civil Code, Article 662 — Sharing the Cost of Upkeep. Read the full provision →
The general rule: renouncing your share
Ordinarily, the cost of repairing and maintaining a party wall is shared by every owner of the properties the wall serves, each paying in proportion to his right in the wall. But the law gives a co-owner an escape hatch: he may exempt himself from that charge simply by renouncing his part-ownership of the wall. Once he gives up his share, he stops being one of the people the repair bill is divided among, and the remaining owners absorb the cost between themselves.
Why the exception exists
That escape hatch closes the moment the wall is doing more than separating two lots. If the party wall supports a building belonging to the owner who wants to renounce, he cannot use renunciation to avoid paying for its upkeep. The reasoning is straightforward: a wall holding up your own roof is not something you can walk away from without also walking away from the structural safety of your house. Letting an owner dodge the repair bill while still relying on the wall to keep his building standing would shift the cost of his own convenience onto his neighbors.
What this means in practice
If your house rests on or is braced by a party wall, you remain liable for your proportionate share of repair and construction costs for as long as that support exists, no matter what you say or sign about giving up your ownership interest. The same cost-sharing rule extends to fences, live hedges, ditches, and drains that are owned in common, so the underlying principle is not unique to walls: whoever benefits from a shared structure that supports their own property shares in keeping it sound.
Who else this rule binds
The obligation follows whoever currently owns the property the wall supports, not just the original builder. A buyer who purchases a house resting on a party wall inherits the same duty to contribute toward its upkeep, because the duty is tied to the fact of support rather than to who first agreed to it. Refusing to pay does not remove the wall's structural role, so a co-owner who ignores a repair assessment while still relying on the wall risks the other owners pressing the claim, or the wall deteriorating for lack of maintenance until it threatens the very building it holds up.