PLUMBING

Plumbing is any system that conveys fluids for a wide range of applications.Heating and cooling, waste removal, and potable water delivery are among the most common uses for plumbing however plumbing’s not limited to these applications.^[1] Plumbing utilizes pipes, valves, plumbing fixtures, tanks, and other apparatuses to convey fluids.^[2] Trades that work with plumbing such asboilermakers, plumbers, and pipefitters are referred to the plumbing trade. In the Developed world plumbing infrastructure is critical for public health and sanitation

Once, state-of-the-art in plumbing was cast-iron drains and brass supply pipes. Now, those materials have been supplanted (for the most part) by PVC plastic, copper, and flexible cross-linked polyethylene, known as PEX. But whether the pipes are plastic, metal, or a combination of the two, it’s the plumber’s skill that determines how well the system works. A lot is at stake: One leaky joint can cause thousands of dollars worth of damage. An undersize, improperly sloped drain will continually clog. And supply pipes that aren’t anchored every 6 feet or so will rattle and thump every time a faucet is turned off.

There’s more to proper plumbing than just following the codes and rules. Planning and installing a system that’s quiet, efficient, and leak free is something of an art. You’ll see it in the way a good plumber arranges pipes and valves for ease of maintenance, avoids wasting material or weakening framing, and takes care to wipe joints clean. “Too bad so much of our good work gets buried,” Richard laments. Turn the page for a look at a system that meets his exacting standards.

The Pipe Network
Clean water enters a house at a pressure of 50-60 psi through the supply lines. Dirty water, pulled down by gravity, exits through the drainpipes, while air coming through the vents keeps the drains flowing smoothly. It’s a wonderfully simple and durable setup. Valves may wear, hoses may break, and appliances will fail, but the underlying network of pipes should last as long as the house itself.

Turn Off the Taps
Modern plumbing has made it easier than ever for us to get clean water—and to waste it. “We have to change the mind-set that we can just turn on the water and let it run like Niagara Falls,” Richard says. He considers the 1994 law mandating low-flow, 1.6-gallon toilets and 2.5-gallon-per-minute faucets and showerheads a step in the right direction. What about those pre-’94 water-wasters? Refitting them with dams, flow restrictors, and aerator devices can make them as water-efficient as a new fixture, or even more so.

1. Shutoff Valves for Every Fixture and Appliance
Individual shutoffs allow you to quickly isolate a problem without cutting the water supply to the rest of your house. After plumbing a house, Richard always leads the owner in a guided tour of all the shutoff valves, most notably the main shutoffs.

2. Don’t Skimp on Vents
Codes dictate the proximity of vents to drains, and the rules should never be ignored. If the vent is too far away, it won’t be able to break the vacuum and allow fast drainage. “When you pull the plug on a bathtub,” says Richard, “you’ve got 40 gallons of water that want to scream down that pipe. If there’s a vacuum, it can pull the water out of all the traps in the house.”

1. Shutoff Valves for Every Fixture and Appliance
Individual shutoffs allow you to quickly isolate a problem without cutting the water supply to the rest of your house. After plumbing a house, Richard always leads the owner in a guided tour of all the shutoff valves, most notably the main shutoffs.

2. Don’t Skimp on Vents
Codes dictate the proximity of vents to drains, and the rules should never be ignored. If the vent is too far away, it won’t be able to break the vacuum and allow fast drainage. “When you pull the plug on a bathtub,” says Richard, “you’ve got 40 gallons of water that want to scream down that pipe. If there’s a vacuum, it can pull the water out of all the traps in the house.”

A well-designed plan is essential for a trouble-free home plumbing system.

Plumbing works on the simple concept of “water in — water out.” In a new home, the plumbing system features three main components, the water supply system, the drainage system and the appliance/fixture set. In most communities, in order to install plumbing, you must be a licensed plumber or you must work under a licensed plumber who approves and oversees your work. Local codes determine standard plumbing procedures, but a new home’s fixture placement, pipe routing diagram and pipe size depends on the home’s individual layout.

Installation Timetable

Sewer accommodation stubs are set before pouring the concrete foundation, but the bulk of the plumbing takes place later. The rough-in plumbing phase, which occurs in conjunction with the wiring and duct installation phase, takes place after the framing is complete, but before hanging drywall. This is the time to install main drains in floors and connect them to the stack. Rough-in drain fittings install now for sinks and tubs. This is also the time to install water supply pipes or tubing and set toilet flanges.

Plumbing Fixtures

Because they’re often too large to set once walls and doorways are framed, tubs and tub/shower units are typically set before framing the walls. Since a lot of construction has yet to take place, cover these fixtures with cardboard or even old blankets or rugs to protect them from scratches. Set and connect sinks and commodes last, after finishing the walls and laying the flooring

Water Supply System

The main pressurized water supply line enters the house below frost line, then splits into two lines; one supplies cold water and the other connects to the hot water heater. From there, the two lines supply hot and cold water to each fixture or appliance. Some homes have a water supply manifold system featuring a large panel with red valves on one side and blue valves on the other side. Each valve controls an individual hot or cold tube that supplies water to a fixture. Using a manifold system makes it simple to shut off the supply of water to one fixture without shutting off water supply to the whole house.

Drainage Pipes

A main vent-and-soil stack, which is typically 4 inches in diameter, runs vertically from beneath the ground floor to above the roofline. Waste drains connect to the stack, directing waste downward to the main sewer drain, which then exits the home below frost line and ties into the municipal sewer system or runs to a personal septic system.

Vent Pipes

Without a constant source of air, water locks can form in drainpipes, causing clogs. All drains require ventilation, but a single vent, usually installed behind a sink, can serve additional fixtures and appliances that connect within 10 feet of a common drain line. Vent pipes, which are generally 2 inches in diameter, connect to the vent-and-soil stack in the attic. When a fixture sits too far from a common vent, it requires an additional vent pipe, which connects to the stack or exits the roof separately, depending on the home’s layout.

How to Install a PEX Plumbing System

STEP 1

Drill Through the Stud and Sill Plate

Place the bit up to the stud and slowly start the drill, allowing it to build up speed.

Drill through the sill plate and sub-floor for each water line. When drilling through a stud, be sure that each hole is at the same level so the pipe runs parallel to the floor.

STEP 2

Run the Water Lines

Once the holes are drilled, start running the water lines. In most cases, the lines will come through the floor. In some cases, the lines will have to be run across the wall studs. When running the pipes through the studs, first be sure to drill the holes in the center so that when it’s time to hang the wall board, the screws or nails don’t reach the pipes and damage the pipes.

Note: Take this extra precaution — Ed recommends using a nail plate. The nail plate has tacks on both ends of a flat piece of steel. Line them up to cover screws or nails so they don’t penetrate the steel to damage pipes.

STEP 3

Pull and Secure the Lines

Pull the lines up through the holes drilled in the sub-floor (Image 1), and then run the other end to the area where the water will be coming into the home. Be sure to leave extra pipe on both ends of the run.

Secure the line to the joists using clamps (Image 2). Do your best to separate the hot and cold lines to minimize heat transfer.

Leave a little slack in the line to allow for expansion and contraction. Don’t forget to label both ends of the line.

 

STEP 4

Do the Rough Stub Outs

It’s now time to do the rough stub outs for the sinks. A rough stub out is installing a special copper fitting that will adapt to the PEX. Notice at the end, there is a cap called a rough fitting, which allows you to charge up the system with air or water to test to see if there are any leaks. After the walls are up, you can cut off the cap and install the finish valves.

Pro Tip

When roughing in the lines, use a right-angle drill with an auger bit or paddle bit.

STEP 5

Apply Crimps

The crimps are the most crucial part of the project. If they aren’t done right, the system could leak and cause problems down the line. There are two kinds of crimping tools. They both work pretty much the same, except one is more heavy-duty. If you’re doing a lot of crimps — use it.

For the perfect crimp, start by cutting the PEX and make sure it’s straight. Slip a crimp ring onto the pipe, and then slide the pipe into the fitting. There’s a little shoulder on all the fittings — that’s where you slide the PEX to. Use a pair of slip-joint pliers or your fingers to slide the crimp ring up. You’ll know it’s in position when it’s between an 1/8″ and 1/4″ or closer to the end of the pipe. This step is crucial to ensure leak-free crimps. The crimp can’t be further than a 1/4″ or closer than 1/8″ to the end. Position the crimping tool so it completely covers the crimp ring. Close the jaws as tight as possible.

 

STEP 6

Rough in the Lines

Now it’s time to rough in the lines to a fixture. Since you can’t solder around the PEX piping, use a fitting called a PEX 90 that sweats right into place on a mixing valve. Once it cools from soldering, it can be safely connected it to the PEX water line.

It’s crucial to take a mixing valve apart before soldering it. Remove any parts that might be affected by the heat from the torch. Use your standard soldering techniques when preparing the valve and fittings.

 

Pull and Secure the Lines

Pull the lines up through the holes drilled in the sub-floor (Image 1), and then run the other end to the area where the water will be coming into the home. Be sure to leave extra pipe on both ends of the run.

Secure the line to the joists using clamps (Image 2). Do your best to separate the hot and cold lines to minimize heat transfer.

Leave a little slack in the line to allow for expansion and contraction. Don’t forget to label both ends of the line.

STEP 7

Position the Fittings and Solder

Once prepared, position the fittings so that they both will face down when the valve is hung in place. Solder them into position. Be sure to let the valve cool completely before putting it into place.

 

STEP 8

Connect the Water Lines

The water lines can now be brought up from the crawlspace and connected to the manifold. Position the manifold about eye level, and then screw the top mounting bracket to the studs. Make sure that it’s level and secure. Attach the manifold to the bracket using the manufacturer’s supplied screws. Install the bottom bracket to the manifold. Check to see that it’s plumb before mounting the bracket to the studs.

STEP 9

Mark and Drill the Holes

Align the template to the manifold on the studs and either mark each hole with a nail or drill directly into it. Continue down the line until all the holes are drilled.

Be careful not to damage the manifold with the drill. You may need to take the manifold down when drilling.

STEP 10

Position the Ball Valves

With all of the holes drilled and the manifold mounted, attach the PEX ball valves to the manifold. Reach up, find the port and screw it into place. Get one of the lines and bring it up to the valve. This ensures that each fixture gets its own shut off valve.

When the ball valves are in place, pull the PEX lines up from the crawl space, being careful not to kink them.

YOU CAN SEE ALL THESE FROM THIS LINK

http://www.diynetwork.com/how-to/skills-and-know-how/plumbing/how-to-install-a-pex-plumbing-system