Ultimate Guide to Types of Plumbing Systems

There are few things more important in any home or business than a top-notch plumbing system — just ask someone who has lived through catastrophic plumbing fails, or a plumbing pro who has had to do the clean up. Our fantastic plumbing customers at Goodin are some of the hardest-working pros in the business, and they earn every dime. From emergency calls on holidays to auguring out main drains, they keep homes and businesses safe, sanitary and humming along.

As part of our HVAC and Plumbing Basics series, we're highlighting the most common types of plumbing systems out there, giving a list of their components and the types of pipes typically used to configure these systems, and spotlighting some common problem pros encounter on the job.

Potable Water Plumbing Systems

Potable water systems supply the water we drink to homes, businesses, properties and other structures. When your customers turn on the tap, they're "tapping" into their potable water supply system. Potable water supply systems are designed to provide clean and safe drinking water to a building or property. They're connected to a municipal water supply or private well.

Potable water systems include:

  • Main water service line. This pipe connects the house or building to the water supply line, usually through the basement.
  • Pipe system. These are the pipes that snake through the structure supplying water to various fixtures, from the kitchen sink to the shower in the bedroom to the laundry in the basement.
  • Pressure regulator. These control the water pressure running through the building.
  • Shut-off valves. Critical to staving off a water disaster, shut-off valves allow you to turn off the water in various areas.
  • Water meter. It tells the city how much water the home or business is using. Oftentimes, they provide the first clue that there's a leak somewhere, if those readings are higher than normal.

Common problems for plumbing pros to handle:

  • Leaks. The scourge of every plumbing system, leaks happen in areas like fittings, valves and faucets and elsewhere in the pipes themselves, especially if they freeze in cold temps.
  • Low water pressure. A very common complaint among home and business owners, plumbers often encounter clogged pipes, faulty water pumps or, in older homes, too many fixtures or appliances running at one time.
  • Discolored water and clogs. Are the pipes old? Corrosion is a main culprit of rusty, discolored water and many clogs. Replace those old steel pipes!

Sanitary Sewer Plumbing Systems

Sanitary sewer systems take wastewater from homes and buildings to sewage treatment facilities or, in the case of some homes and buildings typically found in more rural areas, a septic tank. These systems are a cornerstone in keeping groundwater free from contamination.

Sanitary sewer plumbing systems typically include:

  • The main drain. The main pipe that connects the home or other structure to the city sewer or septic tank should be inspected every year to clear any potential sources of clogs, roots and other blockages that could cause that pipe to back up into the structure. Nobody wants that.
  • Sewer pump. If the drainage system is below the main line, pumps move wastewater through the drainage system.

Common problems for plumbing pros to handle:

  • Clogs. Nobody wants a stopped up sewer line problem, but it's one of the most common problems for plumbers. It can result from using too much toilet paper, flushing foreign objects or other types of buildup. These snafus are fixed with a snake or auger. But it could be more serious, like tree roots working their way into the main drain.
  • Collapse. Pipes in older homes and buildings have a lifespan, and if pipes collapse, you'll find total blockages and the health hazards that can go along with them. This is a major fix.
  • Odors. Homeowner reporting foul odors? It can be a sewer gas leak. Broken pipes or connections are the usual suspects here.


Drainage and Venting Systems

Working as part of the sanitary sewer system, drainage systems allow wastewater to drain, relying on gravity. The venting aspect of the system prevents sewer gases from getting into the building.

Drainage and venting components include:

  • Pipes. The highway wastewater travels through the structure. These pipes contain cleanouts, which are access areas that let plumbers service the pipe.
  • Traps. These work as part of the venting system to prevent gases from building up.
  • Vent pipes. These let outside air into the system, eliminating odors.

Common problems for pros to handle:

  • Clogs. Similar to sanitary sewer lines, clogs can and do build up with time and everyday use.
  • Sewer line problems. When the main sewer lines have problems, your drainage and venting systems will have problems.
  • Backup or slow drains? There might be a problem with slope. Since gravity is a main tool here, if the pipes aren't sloped correctly, owners will get slow drainage.

Manifold Plumbing System

Commonly used, a manifold plumbing system is a bit more detailed than traditional plumbing systems, but for some people, well worth the effort. A manifold system has a central hub through which the water supply is distributed, and each fixture gets its own line, rather than having a branch system to service fixtures. The key benefit to a manifold system is water savings and a more balanced water pressure to each fixture.

Manifold plumbing systems typically include:

  • Manifold. This is the control center, usually wall mounted in a basement utility room.
  • Lines. The plumbing lines, which increasingly are made of PEX, go from the manifold to each fixture.
  • Valves. Valves on each line allow for shut offs to individual fixtures without having to shut down the whole system to, for example, repair a line to the dishwasher.

Common problems for plumbing pros to handle:

  • Flow trouble. A manifold system regulates flow to each fixture. But if the system isn't properly installed, some fixtures may get less water than they need.
  • Leaks. Like any plumbing system, leaks can plague manifolds. It's usually at the connections or valves, which need to be tightened or replaced. In some cases, the valves can outright fail.
  • Airlock failures. Trapped air can impede the flow of water. Bleeding the pipes can fix this common problem.


Type of pipes commonly used for plumbing systems

There are many types of pipes to create a plumbing system. Which type is right for which job? Here's a quick look at options.

Galvanized steel and cast iron. These pipes, typically used for water supply, drain and venting, are found in older homes. Plumbers know these pipes aren't commonly being used in new construction or to replace older pipes today. You're likely taking these out and replacing them with newer, healthier, better options.

PEX. Cross-linked polyethylene is an extremely popular pipe option with pros and DIYers. It's durable, inexpensive and very flexible, allowing for ease of installation. PEX is great for water supply lines, and an added bonus for us in the Midwest, it can help against pipes freezing.

PVC. Installing a drain, waste and vent? PVC is your go-to. It's lighter and more economical than cast iron, and easier to install and configure.

ABS. Like PVC, this type of pipe is great for drain lines and venting lines.

Copper. Yes, rigid copper pipes are made from copper, but they're the gold standard for water supply lines. While more expensive than plastics, retrofit or transition to plastics can be an advantage.

Supply tube. This is the tubing, plastic-chrome (copper) or Flex, you'll use to connect the main pipes to fixtures like toilets, dishwashers, and sinks. Not to be used inside walls or under floors, this is the "finishing" piece that connects your plumbing puzzle.

Pro tip for pipes: Always check the local codes before installing any type of pipe.


At Goodin Company, we've been partnering with plumbers for 85+ years and counting. We're your source of supply for any project, large or small. Contact us today to find out more.

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