Does liquid drain cleaner harm pipes?

Written by roz calvert | 13/05/2017
Does liquid drain cleaner harm pipes?
Look before you pour liquid drain cleaner in old or plastic pipes. (Exterior Plumbing 8 20080713-1210426 image by SIGNSofMIND from

A clogged pipe can put a sink out of commission for days. To get relief, many people run to the store and grab a liquid drain cleaner off the shelf. It sometimes works like a charm and the problem vanishes. Other times, however, it scarcely moves the gunk from the pipes and a plumber is called. He fixes the problem, but sometimes warns that using liquid drain cleaner can damage your pipes.


Liquid drain cleaners are chemical- or enzymatic-based. They burn or eat away the blockages in drains. Enzyme cleaners essentially digest the blockage and they rarely cause pipe damage. Chemical cleaners work because of their reactive nature. The interaction of the chemical with the material causing the clog creates gaseous heat to burn it.


Chemical drain cleaners are classified in three different ways: acids such as sulphuric acid and hydrochloric acid; oxidisers like sodium hypochlorite; or caustics, including caustic soda, lye or sodium hydroxide. Of these, any can cause damage to plumbing, but the most likely to do so is a liquid drain cleaner containing a caustic ingredient. Limited use of these chemicals, however, does not always cause damage to pipes.


When the gases burn through the clog, they also may burn through the pipes or fittings in your plumbing system. Homes have pipes made of several different substances. Galvanised steel, copper and PVC plastic are the most common. Liquid drain cleaners that contain caustic, acid or oxidising ingredients may corrode or burn through some of these pipes. They also can exacerbate problems with pipes that already are corroded. The problem usually occurs when homeowners use excessive amounts of the cleaner, or use them frequently and on a regular basis.


There are a few different approaches to drain clog removal that do not involve chemical liquid cleaners. Try the enzymatic drain cleaner in combination with a plunger and drain auger, or drain snake. Alternately, a combination of one 473ml box of baking soda and one 454gr bottle of white vinegar left to work on the clog overnight can sometimes dislodge it.

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.