If within a reasonable time after notice to the lessor, of dilapidations which he ought to repair, he neglects to do so, the lessee may repair the same himself, where the cost of such repairs does not require an expenditure greater than one month’s rent of the premises, and deduct the expenses of such repairs from the rent, or the lessee may vacate the premises, in which case he shall be discharged from further payment of rent, or performance of other conditions.

SOURCE: CC § 1942.