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A Detailed Explanation of Bathtub Plumbing

How a Bathtub Works

The bathroom is one of the busiest rooms in the average house. The bathtub specifically probably gets used several times a day. But, while people use it to relax with a hot shower at the end of a hard day, they probably don't think of how the bathtub provides them with the perfect balance of hot and cold water and faithfully drains the dirty water away. But as a homeowner, it is helpful to understand bathroom plumbing

Understanding the Plumbing System

a plumber working

Plumbing systems can seem overwhelmingly complex at first, but in reality, they are fairly simple. It all starts at the main water line at a water meter. A single line carries water to a single point in the home. A branch is added to this line to fill the hot water tank. The cold and hot water lines then branch out to every plumbing fixture in the house as needed, including toilets, sinks, dishwashers, bathtubs, outdoor hose bibbs and washing machines.

Each fixture will have a drain of some sort to carry away soiled water. The drains of all the appliances tie together and become what is called a "sewer main." The sewer main carries away all of the soiled water back to the municipality for treatment or to a septic system. 

How Bathroom Plumbing Works

The bathroom is supplied by a branch of the cold water and a branch of the hot water. Both sets of pipes will run to sinks and bathtubs while only the cold water will run to the toilet. The water waits in the pipes until a fixture allows water to flow into a basin, tub or toilet. This is where a lot of plumbing problems are the most noticeable. Fixtures are more complicated and have more moving parts than the rest of the plumbing in a home, so they are prone to breaking down more often. 

a clean bathroom

Under each basin, tub or toilet, the drainage system begins. The first part of any drain is a p-trap. A p-trap is an upward bend in a drain that constantly allows some water to stay inside the pipe. The water in the p-trap prevents sewer gas from leaking back into the house. 

After the p-trap, drains are quickly tied together under the bathroom floor so that the fewest number of pipes are flowing into the sewer main. This is the reason that serious drain clogs appear in bathtubs and toilets simultaneously. 

Specifics of Bathtub Plumbing

a plumber working

Bathtubs can be slightly more complicated simply because the single faucet controls the showerhead and the spout, meaning more moving parts. The faucet is fed by copper or PVC pipes that run hot water and cold water to the separate handles on the faucet. When turning the handles, hot and cold water mix and flow out the spout or divert upward to the showerhead. 

Soiled water flows out in the same way that it would a sink. A p-trap is still present in a bathtub, although it is probably hidden from sight there whereas it can be seen underneath a sink. The soiled water flows through the p-trap and down a pipe until it meets up with other drains and flows to the sewer main. 

About Alberta Indoor Comfort

Alberta Indoor Comfort has been serving the residential and commercial plumbing needs in the Alberta area since 1996. Their mission is to provide families with a safe and comfortable environment. They have what it takes to help with any plumbing needs from drain cleaning to emergency plumbing service.