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Why Your Drains Smell Bad (And What to Do about It)


Nobody wants to have a house the smells unpleasant, for any reason. If you make a special effort to keep a clean house, but then find that foul odors are coming from one or more of the drains, it can be frustrating. There are various reasons for this to happen, and fixing the problem can be simple—or something that will require professional plumbers. Below we’ll look at the causes of bad smelling drains and how to get rid of them.

Dried-out p-trap

The p-trap is the curved pipe placed directed under a drain. The purpose of this curved pipe is to trap water to create a barrier against sewer gas flowing the wrong direction up the pipe and out the drain. If a drain isn’t used often (such as a sink in an empty guest room), the water in the p-trap will evaporate and allow sewer gas through. You only need to let water flow down the drain for a minute or so to restore the water in the p-trap.

Clogged drain vents

Your plumbing system has vents in it to prevent the build-up of pressure between the drains and the sewer line because of sewer gas. These vents allow the gas to escape up through the roof of the house. If these vents become clogged up, it will force the gas to take the easiest escape route it can find… which will be to force itself up through the water in the p-trap. Professional plumbers can track down where the vents need repairs and take care of fixing them.

Damaged sewer line

This is the most urgent problem since a sewer line that is broken or blocked will eventually cause sewage to back up into your home. If more than one drain is emanating foul smells, then it’s likely that a sewer line problem is the issue, and you need to call professional plumbers right away. Fixing or replacing a damaged sewer line is a major job, but our plumbers use the best in trenchless technology to do the work fast and accurately.

Mallick Plumbing & Heating offers drain cleaning to Silver Spring, MD, and the surrounding areas.