But how often do you think about just how all of the pipes, valves, and drains in your house are connected?

Wonder no more! Here’s a very basic beginner’s guide to the layout of your home’s plumbing. Think of it as a road map for the next time you call in a plumber or try to tackle a DIY project of your own.

From top to bottom, here's how your plumbing system connects and flows: 

ATTIC & ROOF

The attic is typically not home to many water lines in most homes (though there may be hot or cold lines running through your ceiling, the attic itself is most likely too variable in temperature to house pipes safely, even with insulation). Instead, it’s most notable for housing the vent stack, which feeds out through your roof in order to allow sewer gases to exit your system while allowing oxygen to get in.

TOP FLOOR

Let’s assume the top floor of this house features a full bathroom, including a sink and a shower.

With a typical drain-waste-vent (DWV) system, the vent stack here splits into numerous lines leading to your appliances, such as sinks and showers. Here, the vent lines connect to your home’s drain system at numerous intersections.

Drainage works as you might expect: Water moves down through drains in your toilet, shower, and sink, moving through a series of bent areas, called traps (designed to catch debris and prevent gases from building up) as they go. From here, water flows into one central trunk-like line, called the soil stack or main stack, which continues down all the way into your basement. In some systems, there may be a separation between the soil stack and a waste stack: In these cases, the soil stack carries drainage from sanitary fixtures (i.e., toilets) while the waste stack feeds from any other vertical drain pipe (such as sinks).

MAIN FLOOR

Moving downward, the soil stack continues to carry waste water toward the ground. Any other appliances or fixtures on your main floor – such as a kitchen sink or dishwasher, or the toilet and sink in a ground-floor half-bath – work the same way as units on your top floor, with drainage flowing into the soil stack by means of soil pipes, and gases flowing upward as part of the DWV system. 

Most notably, the ground floor most likely is where outdoor plumbing units (such as spigots and hose bibs) are located, as well as your water meter and emergency shutoff valve, though in some cases, these may be located in...

THE BASEMENT

The basement is home to some of your home’s most fascinating and complex plumbing features.

Here, the soil stack continues to carry waste and drainage downward. Finally, it travels down and out of your home, connecting by means of a main drain to the sewer or a septic system. If your home has a basement bathroom, a washing machine, a sump pump, or an ejector pump/backwater valve, all of these are going to connect to the soil stack or waste lines here, as well.

So that’s how water exits! In most systems, water typically moves into the home here in the basement, as well, by means of supply lines. Water may move through a water softener before heading toward the water heater. From there, a certain amount of water goes through your water heater by means of intake and output pipes. A series of pipe lines – some for cold water, some for hot – carry water up and around to all of the appliances in your home – and the cycle continues!

Now, of course, it’s important to keep in mind that not all homes are alike – maybe your water heater is on the ground floor, your shutoff valve is in the basement, or your washer/dryer are located on your top floor or in a garage. We’ve simplified things enormously here, but the experts at Combat Plumbing will be the first to tell you that no two systems are exactly alike, and that making sure every part of the plumbing system is in working condition can be a tall order.

 

That’s why it’s so important to have a reliable plumbing pro on speed dial! Whatever your plumbing or ventilation needs, Combat Plumbing is here to help, day or night. Drop us a line to see what our family can do for yours!