A residential plumbing system is designed to bring clean water into the home and carry wastewater away. Many homeowners take home plumbing systems for granted and never learn how they work. Understanding the basics of a home plumbing system can help you recognize potential plumbing problems early.
We’re going to break down how your home plumbing system works, so you can be better informed about plumbing system components.
The Two Main Parts of Your Plumbing System
Residential plumbing systems are made up of two main parts: the water supply system and the drain-waste-vent system.
Water Supply System
It is the water supply system’s job to bring fresh, pressurized water into your home. This system starts at the main water line and uses a network of pipes to bring water to your fixtures, including sinks, showers, and toilets. The system includes shut-off valves, a pressure regulator, and generally, a water heater that splits the system into hot and cold lines.
Drain-Waste-Vent System
The drain-waste-vent (DWV) system carries waste and wastewater out of your home and into the sewer or septic system. This system is not pressurized, and instead relies on gravity, so pipes are angled to allow waste to flow down and out. Vent pipes let air into the system to help wastewater flow smoothly and allow sewer gases to escape outside instead of inside your home.
How Water Gets Into Your Home
Wondering how water actually gets into your home? The main water supply line is the pipe that connects your home to the municipal water main (or your private well) for the fresh water your household needs. Water generally enters through a basement, crawlspace, or via a buried line near the foundation.
After the line where the water enters your home, you’ll typically see a water meter that measures the amount of water used and the main shut-off valve which controls water flow to the whole home. Water then travels through a network of pipes running through the walls, floors, and ceilings to reach fixtures, such as toilets, sinks, showers, etc.
Supply lines are generally made from copper, PEX (cross-linked polyethylene), or CPVC (chlorinated polyvinyl chloride), depending on your home. Copper lines are highly durable and bacteria resistant but more expensive. PEX is flexible, affordable, and easy to install, while CPVC offers rigidity and corrosion resistance.
Understanding Water Pressure
Water pressure is what pushes water through your home plumbing system and out of your fixtures. Water pressure is generally measured in pounds per square inch (PSI), and most homes' optimal water pressure falls between 40 and 60 PSI.
Water pressure is essential to home plumbing systems because it allows water to travel upward through walls and floors to reach faucets and other fixtures. Without adequate pressure, water wouldn’t be able to move efficiently through the system.
The right water pressure is essential to residential plumbing systems because both low and high water pressure can cause problems. Low pressure can cause frustration with weak flow issues or appliances that take longer to fill. Low water pressure can be caused by clogs in the line, hidden leaks, and mineral buildup.
High pressure can put extra strain on fixtures, pipes, and fittings, often leading to premature wear or burst pipes over time. A pressure-reducing valve helps keep pressure levels safe for your home plumbing system.
How Your Plumbing Fixtures Work
Next, we’ll briefly touch on how common plumbing fixtures work.
Faucets
Faucets control the flow of water at sinks using a valve or cartridge system to regulate how much water comes out and at what temperature. Many modern faucets utilize a single-handle cartridge which is less prone to leaks than compression-style faucets with separate hot and cold handles.
Toilets
Toilets operate by releasing water stored in the tank into the toilet bowl when you flush. The release of water creates enough force to clear waste through the trap and into the drain line. The toilet uses a flapper valve to control the water release from the tank and a fill valve to refill the tank.
Showers & tubs
Showers and tubs are connected to the water supply system, which provides hot and cold water, and DWV system, which carries wastewater away. Most modern showers and tubs use mixing valves to blend hot and cold water to reach your desired temperature and anti-scald features. Drains generally use a stopper or trip-level mechanism as well as a P-trap to keep water flowing without allowing sewer gases to come back in.
How Wastewater Leaves Your Home
Wastewater travels from individual fixtures into branch drain lines to flow into the municipal sewer or septic system. Each fixture uses a branch drain line that's connected into larger drainpipes that combine the flow from multiple fixtures. The pipe size gradually increases in diameter as more wastewater joins the system and eventually feeds into the main line.
Gravity is the driving force for wastewater removal. Drainpipes are installed at a slight downward slope to encourage wastewater to flow naturally towards the main line without the need for pumps. Proper pipe slope is essential to residential plumbing systems to prevent clogs.
After the main drain line, wastewater exits the home and connects to the municipal sewer system or a private septic system. In the case of the municipal sewer system, wastewater is sent to a treatment facility, whereas with a private septic system, wastewater is filtered on site.
What Are the Signs that Your Plumbing Needs Professional TLC?
There are many signs that your home plumbing system may need professional repair. Some of the top red flags include:
- Persistent leaks
- Repeated drain clogs
- Multiple slow drains
- Discolored water
- Sudden changes in water pressure
- Unexplained increases in water bills
- Sewage odors
- Water stains or damp areas
- Noisy pipes
- Frequent sewer backups
Contact Us Today
If you notice any of the signs we listed in Tacoma or Silverdale, WA, give Mercurio’s a call at (360) 499-2980 for professional plumbing services or book online. Our licensed plumbers are ready to help get your home plumbing system back in order.
