4 Common Causes of Sewer Odor in House

If you notice a smelly sewer odor in your home, there are several possible causes. Here are some things to check: 

1. Check the floor drain trap. Without water to block the sewer gas from escaping, odors will enter the room. Pour water down the drain to refill the trap. 

2. Check the cleanout plug inside the floor drain. Remove the grate that covers the drain, and make sure there's a plug inside the drain bowl. If the plug is missing, sewer gas can bypass the water trap. A replacement plug can be bought at most hardware stores. 

3. Check the toilets. When toilets are unused for a long period of time, the water in the trap can evaporate. Simply flushing the toilet will refill the trap. 

4. Check toilet wax rings. The wax ring seals the toilet flange to the toilet base. If the wax ring leaks, sewer gas will escape from under the toilet. If the ring is broken, the toilet will need to be removed and the wax ring replaced. If the toilet is loose on the base, shims can be used to ensure that a rocking toilet doesn't break the new wax ring. 

Other possible causes of sewer odors include a broken or cracked sewer line or, less often, a loose connection joint in an interior wall. If you've checked the other possibilities above, it may be time for you to contact your plumber to hunt down the cause. 

Have sewer and drain line questions? Call ABC Plumbing, Sewer, Heating, Cooling, and Electric; we can help.