Connecting fixtures with DIY plumbing

So to run a diy plumbing waterline we know that a main line runs to the water heater, then branches off from the water heater and goes into a cold line and a hot line. The two lines will run as far as the furthest fixture with branches or tees servicing all the fixtures between.

Remember, toilets or water closets only need a cold line. Here are a few examples of some important fresh water fixtures. The diagrams are pretty much standard for copper and galvanized systems.

Apart from the plumbing pipe runs, you will have to know how to connect the fixtures to the pipes.

We will start with the water heater, as it is the first actual fixture in line because it supplies hot water for the other fixtures. Water heaters typically have a ¾ inch cold water line on the intake, a ¾ inch line on the outlet, and a pressure relief valve.

installing water heaters

The relief valve and overflow line need to made of either copper or galvanized because of the possible high water temperature they might have to withstand. Also, in most areas, the overflow will have to be diverted under the floor and outside the foundation onto the ground to prevent anyone from getting scalded.

Let’s move on to some other fixture connections. Bathrooms consist of a sink, a bath/shower, and a toilet. The waterlines will need to be routed so that they branch off of the main lines and into the walls where each fixture will be located. This shows a pretty good plumbing layout.

plumbing diagram

This shows how the shower/bath assembly works. You can usually buy this piece as a whole unit that’s already measured and ready to install. In the picture above you see how to install the sink shut offs with compression fittings.

The fittings will screw onto the pipe nipple. Copper and galvanized pipe nipple fittings have threaded ends for termination fittings to screw on and for branching off of the mainline.

bathroom plumbing

The kitchen plumbing is basically like the bathroom sink except for the difference of a dishwasher, which only takes a hot line.

diy plumbing repair

The laundry room will require a hot and cold line also. The picture above shows how to run the hot and cold lines. These lines are usually brought together in a recessed wall box with spigots to hook up the washer supply lines as well as a waste line for the washer to pump out dirty water.

washer plumbing

This picture shows how the hot and cold supply lines connect to the washer. It also shows the waste water pipe with drain hose and trap. One more thing to think about at this point is that many people like to have a deep laundry sink by the washer to soak extra dirty clothes.

It’s a good idea if you have space to do it because the cost is quite minimal being that the water and waste lines are there already. Deep plastic sinks are very reasonable and really handy if you get dirty a lot.

Before we move on to the diy-plumbing part of the Drain, Waste, and Vent systems, there are a few things I should mention. First, I don’t talk much about galvanized pipe because it is expensive and difficult to work with. If you do have to use it, you can usually rent thread makers from plumbing stores.

It takes a little practice at first, but so does everything. Another thing is that quite often, copper and galvanized pipes will leak around the threads if you just screw them together. I like to use Teflon tape for that. Just wrap the threads a few times before screwing the pieces together.

You can also use RectorSeal on water lines, but it is used more often in small copper propane and natural gas lines. Both are available at any plumbing store.

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