Not all pipes are made out of the same material. In fact, there are many different kinds, both metal and nonmetal, that are being used today. Some, such as galvanized steel, are slowly being phased out as older homes and businesses begin to re-pipe, while others, like brass and PEX piping, are gaining in popularity.
Here is a breakdown of each of the more popular sewer pipe materials.
Brass Sewer Pipes
Brass was one of the more popular piping materials for older homes because of its long lifespan of 80-100 years, and it’s resistance to rust (especially if it’s made of 67-85% copper). They are easier to thread than traditional steel and offer great hot-water distribution.
Brass pipes can easily be used for all of the following:
- Water supply lines
- Water removal drains and lines
- Some applications for gas lines, depending on local building code
Because brass is an alloy, one of the potential problems with this piping material is lead. Lead is highly toxic if consumed. If you have brass pipes, get them tested regularly to see if any lead is leaking into your water from the pipes. If the lead is in a safe range, you have nothing to worry about. If the levels are too high, you should shut off and replace your pipes immediately. Thankfully, most modern brass piping is lead free, so if you’re in the market for brass, lead should not be a concern.
Cast Iron Pipes
You’ll likely see cast iron in older homes that were built pre-1950s. Cast iron plumbing pipes are normally manufactured as bell-and-spigot, or threaded joints. They’re quite heavy and are normally only used for water distribution or underground installations for moving water (like a sewer). It is extremely strong, durable, and both sound and heat resistant.
However, cast iron is highly susceptible to rust overtime. Thankfully, sections can be easily replaced if rust becomes an issue. They’re not commonly used today due to their weight, but are still reliable and safe.
Galvanized steel was popular several years ago and will be found in many homes that were built post-1950. Its lifespan is relatively long at an average of 80-100 years.
Galvanized steel pipes are prone to both rust and corrosion, meaning they’re not reliable in the long term. If your pipes are old enough, you may begin to experience discolored water due to rust, buildup or leaks caused from the corrosion. Because of this, they should be phased out of your home and replaced with a modern material when it’s time to get new sewer pipes.
You can tell if you have galvanized pipes by checking to see if they’re magnetic. Simply grab a flat head screwdriver and a strong magnet. Find your water line and scratch the outside of the pipe with the screwdriver. If the surface looks shiny and silver, and if the magnet sticks to it, then it’s galvanized.
Copper is the most popular piping material for homes built after 1970. It is estimated about 98% of homes built after that time have copper pipes. Copper is designed to last up to 80 years, however, if your water is acidic, it can cause heavy corrosion.
Corrosion of copper pipes will introduce high levels of copper into your tap water, which is a serious health risk. It can also cause leaks, which can damage your home, and let other contaminants in your tap water. Once the dangers of copper pipes became better known, plumbers switched to brass pipes. If your water isn’t acidic, copper pipes hold up well and stand the test of time.
Copper pipes are recyclable too and you can install them outside without much concern.
The downside is that copper pipes are expensive and they may make water taste slightly metallic.
PVC piping is popular for short-term sewer pipes and water drainage. It’s only designed to last 24-45 years, so it will need to be replaced relatively often compared to other piping materials.
PVC pipes offer lightweight options that are safer to install, flexible, and resistant to fracturing. They’re also secure in terms of joint tightness. PVC pipes are available with deep insertion, push-together gasketed or solvent cement joints.
PVC piping is a non-toxic and safe material that has been used for more than half a century. It is also the world’s most researched and tested plastic.
In 1968, German scientist Thomas Engle discovered a way to crosslink common plastic (polyethylene) through radiation to produce a much simpler form of the material, thus creating PEX. Today, it is cross-linked polyethylene tubing that is primarily used for water supply piping systems.
PEX piping is flexible, easier to install than rigid metal piping, is durable, and offers high heat resistance. It also has a lifespan of about 100 years.
However, PEW pipes are not suitable for use outdoors as the sun can break down the material, it cannot be recycled, and it does require special connectors and tools to install.