The lease may contain, or tenancy law may require a lease to contain (which is the same thing, even if the actual lease doesn't have it) a clause regarding uninhabitability.
This means effectively that the house must be inhabitable. This could be a defined term, use a "reasonable person" test, or be left to individual decisions by an inspector.
If this is not the case, or the ubinhabitability clause does not trigger, you may also consider requirements that issues be addressed n a reasonable time, thereafter being grounds for termination of lease.
What counts as "reasonable" can differ based on almost any factor involved; the amount of damage and the availability of any specialist staff or equipment or materials are most likely to matter. Cost should not matter, as that is the landlord's problem and except for "optional" repairs or changes, it cannot usually be made your problem.
Beyond these two areas, you will probably need specific legal advice. To be sure of what clauses and laws may apply to your situation, getting specific legal advice from a qualified and recognised practitioner of law is the best approach.