You can't get all your rent back, but you may be entitled to some compensation. All rentals come with what is known as the "implied warranty of habitability," which is the obligation imposed on the landlord by law that the rental unit and all other leased space be safe, healthy, and fit for their intended use. When the safe, etc. use is impaired, such as by sewage back-ups, foul odors, etc. the landlord is violating the obligation and the tenants may be entitled to monetary compensation. This compensation is generally calculated as a percentage of rent--I usually see percents in the 10% to 25% range. (The reason you can't get all rent back is that if you are living there, you are clearly getting the majority of what you are paying for: a place to sleep and live, a place to keep belongings, etc., and you have to pay for getting those things.) A court will calculate how much it deems your rental "impaired" or "diminished" by the issues, and can award compensation commensurate with that determination.  In addition to seeking compensation, you can also force the landlord to make the necessary repairs or modifications to ameliorate the problem. Landlord-tenant issues can be surprising "technical" and difficult for nonlawyers: you are strongly advised to consult with a landlort-tenant attorney about this issue and your rights.