If the odor is strongest in the kitchen, it could be caused by a buildup of food in your disposal unit. If this is the case, there could be bacteria thriving within the food buildup as well. While hot water and dishwashing liquid may eliminate or lessen the smell, the best thing to do is hire a plumber to thoroughly clean the unit. They know best how to eliminate the food and bacteria and get the unit back into proper working condition.
Perhaps the most serious causes of sewer odors in homes are cracked drainpipes. When drainpipes become cracked, sewer gases can leak into the home, smelling much like rotten eggs. This can be quite an unpleasant smell, and you will want to correct it immediately. If the smell is persistent, it is probably emanating from within the home; whereas, if the smell is occasional, it is probably emanating from outside or under the ground. Again, it is best to call a professional to remedy the situation.
Finally, many causes of sewer odors in homes are blocked vent pipes. These are the pipes that go through the roof of the house, allowing sewer gases to escape into the air outside. If these pipes become blocked, due to such things as leaves or other debris, the blockage will impede the gases from flowing outside, and they will escape into the home instead. An experienced plumber knows best how to clean out vents, preventing gases from invading your home.
These are just a few of the most common causes of sewer odors in homes. There are many other causes, and a professional can easily find your problem and repair it in no time. People should never try to fix these problems on their own, as they often only make the problems worse. Many of these problems are quite complicated and require tools and skills that only professionals possess.