What is Galvanized Pipe?

“Galvanizing” or “galvanization” is the process of applying a zinc coating to steel or iron, so galvanized pipes are simply steel pipes coated in a layer of zinc. This outer layer protects the underlying pipes, preventing corrosive substances from affecting the steel or iron.


There are multiple methods of creating galvanized pipes:

  • Hot-dip galvanizing: This is the most popular coating method, in which the pipes are dipped in molten zinc.
  • Electro galvanizing: The zinc coating is applied using an electrical current; this results in a thinner protective coat, rendering the pipes unsuitable for outdoor use.
  • Sherardizing: This is also known as vapor galvanizing or dry galvanizing. In this process, steel pipes are placed into a closed, rotating drum containing zinc dust and a filler; it is then heated to extreme temperatures.
  • Metallic spraying & painting


Why Was Galvanized Pipe Used?

Galvanized pipe was used to construct indoor plumbing for homes after World War II through the 1960s. They were designed as an alternative to replace lead pipes. Lead used to be the most common material for indoor plumbing pipes as it was cheap, rust resistant, and easy to weld; however, the serious health consequences of lead poisoning filtered them out of use.


Galvanized pipes were considered an ideal alternative to other piping types as well because they were less expensive than copper piping and more durable than plastic. Nowadays, they are rarely used in modern construction and are largely present in only older homes and buildings.


Do Galvanized Pipes Contain Lead?

While the steel pipes do not contain lead, the protective coating is made of naturally occurring zinc. This type of zinc is considered to be impure and contains lead (along with other impurities), so while the coating serves to protect the pipes and lengthens their lifetime of use, it also contains traces of substances hazardous to people’s health.


As the zinc coating and pipes corrode, the lead accumulates, and it can eventually be released into your water supply. If the pipes in your home are reaching the end of their lifespan and are severely corroded both inside and out, the possibility of lead poisoning is high. The only way prevent lead from entering your water stream is to repipe your entire home and remove all galvanized pipes.


How Long do Galvanized Pipes Last?

Galvanized pipes have a functional lifespan lasting anywhere from 20 to 50 years. If the pipes are used to transport hard water (water with high mineral content), then the pipes will corrode faster as magnesium and calcium build up and restrict water flow, shortening the lifespan. To lengthen the lifespan, galvanized pipes must be kept well maintained. Methods include reducing water pressure to minimize strain on the pipes by installing a pressure reducer as well as decreasing the mineral content of hard water by adding a sodium-based softener.


How Do I Know When It’s Time to Replace Them?

You’ll know the pipes are nearing the end of their lifespan and it’s time to replace them when the water pressure lowers. As pipes age, plaque builds up on the inside of the pipe, claiming significant surface area and restricting water flow. You may also experience uneven distribution of water as corrosion can build up sporadically. Corrosion also further results in the discoloration of the water due to increased iron and flakes of the corrosion breaking off into the water stream. Brown stains in sinks and tubs are a common side effect.


The final sign it’s time to replace your pipes (also the most damaging of the signs) is the presence of water leaks. As pipes corrode, the joints weaken and begin to leak. Left unnoticed, leaks cause extensive damage to your home as they often occur out of sight behind walls and under floors. Repairs to the house’s foundation, floors, ceiling, drywall, and sheetrock are often needed as a result of unseen leaks. The excess water encourages mold growth as well and attracts termites which can cripple your home’s wooden structural supports.


How Can I Tell if I Have Galvanized Pipes?

Not sure what type of pipe is in your home? Use this quick trick to determine if you have galvanized pipes. Simply scratch the outside of the pipe with a coin or flat head screwdriver and check the color. Use the provided information below to determine the type of pipe used in your indoor plumbing system:


  • Copper: These pipes are the color of a penny.
  • Galvanized Steel: These pipes are indicated by a silver-gray color.
  • Lead: Look for a dull, gray color. These pipes are usually very soft and easily bendable. If your pipes are lead, then they should be replaced as soon as possible.
  • Plastic: Typically white or black, plastic pipes are also indicated by visible clamps or caps.


In addition to the scratch test, you can determine the material of your pipes with a strong magnet as it will only stick to galvanized steel pipes. Copper, lead, and plastic materials are not magnetic.


Should I Replace My Galvanized Pipes with PEX?

Yes. If you have galvanized pipes in your hope, you should replace them with PEX. PEX piping is made of Polyethylene (PE) that is cross-linked (X). It is flexible, durable, and high-density. Repiping your indoor plumbing system may seem daunting, but PEX is an affordable and convenient choice whose benefits far outweigh the hassle:


  • Do not contain lead components
  • Are less likely to burst than other pipes
  • Do not corrode
  • Unaffected by acidic water
  • Chlorine and scale resistant


Learn more about PEX piping, its advantages, and how it compares to other types of piping here.


Who Can Repipe My House?

To replace your galvanized pipes, get in touch with a local repipe company that specifically specializes in replacing indoor plumbing. At The Repipe Company, we’re a team of certified technicians dedicated to providing top-quality service and installation for residential homeowners in Houston, TX. Learn more about our mission, and if you’d like to receive a free consultation with our repipe specialists, contact us today.