Short answer. Yes, generally. Article 1298 makes a novation void only when the original obligation itself was void. A merely voidable obligation is different: novating it can operate as ratification, which validates the voidable act, so the new obligation stands unless the annulment right belonged exclusively to someone other than you as debtor.
What the law says
The novation is void if the original obligation was void, except when annulment may be claimed only by the debtor or when ratification validates acts which are voidable.
Civil Code, Article 1298 — Void Original Obligation. Read the full provision →
The default rule: void original, void novation
Article 1298 states the default rule plainly: the novation is void if the original obligation was void. This makes sense because novation works by substituting a new obligation for an old one, and if there was never a valid old obligation to begin with, there is nothing for the new one to replace. A void original obligation produced no valid rights or duties in the first place, so an attempt to novate it inherits that same nullity rather than creating something new and valid.
The two exceptions the article carves out
The article then carves out two exceptions to that default rule. The first applies when annulment may be claimed only by the debtor — meaning the flaw in the original obligation was one that only the debtor could invoke to have it annulled. The second, and the one that matters for your situation, applies when ratification validates acts which are voidable. A voidable obligation, unlike a void one, is valid and binding until it is actually annulled by someone entitled to seek annulment; it is not automatically a nullity.
Why a voidable debt is different from a void one
Because your original debt was only voidable rather than void, it falls outside the article's harsh default rule. A voidable obligation produces legal effects unless and until annulment is actually pursued, so there was a genuinely existing obligation available to be replaced through novation in the first place. That is the key distinction: the void-original rule targets obligations that never had legal existence, while a voidable obligation remains a real obligation right up until it is annulled.
What ratification through novation means practically
Going ahead and novating a voidable obligation, instead of having it annulled, is treated by Article 1298 as an act of ratification that validates it. Ratification is essentially the party entitled to seek annulment choosing to affirm the obligation instead, and novating it is one way that choice can be expressed. Once ratified in this way, the underlying voidability is cured, and the new obligation created by the novation stands as a valid substitute for the old one.