How To Install A Kitchen Faucet: 10 Easy Steps

It would be great if you could install a kitchen faucet just once and have it last for as long as the kitchen, but unfortunately, nature isn't on your side. If hard water deposits don't eventually clog up the works, rust is sure to corrode internal metal components, and eventually, you're going to need a new kitchen faucet. Of course, it's also possible that you want a style upgrade long before your old faucet wears out. The upside of faucet replacement is that it's a home improvement project you can do yourself, assuming you're cool with working on your back in the dark, confined space under the kitchen sink.

While no single installation procedure applies to every faucet, the same general process applies to most of them except for those with "touch" or "touchless" technology. This feature requires special parts, and these supplemental parts are often particular to the faucet model. Most supplemental parts come in the box with the faucet, so you shouldn't have to do any extra shopping unless, of course, you're attempting a DIY retrofit of a used faucet from another part of the house or from a store that sells recycled building materials, such as Habitat for Humanity's ReStore.

Before you commit to a DIY faucet replacement and move on to a step-by-step procedure, you should take a moment to ask yourself these questions:

• ​Do you have the right faucet?​ The number of holes in the sink must correspond to the number of holes the faucet requires. You can't install a double-handle faucet with two separate water inlet posts on a sink or countertop with a single hole. If your sink has three holes and you want a single-handle faucet with one post, you need a model with a baseplate to cover the unused holes (you can cover the holes with caps, but these are usually unsightly). If you choose a faucet with a side spray, the sink or countertop has to have an extra hole to accommodate it.

• ​Are the shutoff valves operable?​ A common problem encountered when replacing a kitchen faucet is that the supply valves under the sink have rusted and fused or worse, they are leaking. You have to be able to shut off the water to complete the procedure. You can shut off the water to the entire house, but it's always good to have shutoff valves under the sink. So, if yours are in bad shape or you don't have any, replace the old ones or have a plumber install some.

• ​Will I be able to use the sink tonight?​ If everything goes smoothly, replacing a kitchen faucet is a job that takes one to two hours. Sometimes, the mounting nuts are so thoroughly fused that you have to cut the faucet free with a hacksaw, and that can easily add an extra hour or two to the procedure.

• ​Is it worth it to DIY the job?​ A plumber will charge $75 to $100 per hour to do the job and will probably complete it in one to two hours even if things don't go smoothly. Most professional plumbers charge a service fee on top of their hourly rate that can be from $75 to $125, so you could be saving almost $400 by doing the job yourself.

• ​Is the new faucet good enough?​ While you don't have to spend top dollar on the newest, trendiest kitchen faucet available, budget faucets are seldom worth the cost savings. Low-quality faucets are prone to problems and typically wear out much quicker than good-quality models. As a general rule, stick with well-known brands, and choose a midpriced or better model. Even some of the big brands offer cheap faucets that aren't worth buying.

The tools you need for this project are mostly ones that you find in a typical homeowner's toolbox, but there are two you might not have:

• ​A​ ​headlamp,​ which shines light where you're looking and illuminates the tight, narrow space between the back of the sink and the wall.
• ​A​ ​basin wrench​, which locks onto mounting nuts of any size and allows you to torque them loose by turning a long handle that extends below the bottom of the sink where there is plenty of clearance to work.

You can find everything you need for this project at a hardware store or home center. Be sure to check the size of the shutoff valve outlet and the faucet connection to get the right flexible supply hoses (they can have the same or different sizes of fittings at their ends).

1. Clear Out the Sink Cabinet

Remove everything from the sink cabinet, including shelves, to give yourself as much working room as possible. It's a good idea to disconnect and remove the sink P-trap to get it out of the way, and you may also want to disconnect the garbage disposal and remove it. Don't worry if these jobs are beyond your skill level or if you don't have time for them. You can still do the faucet replacement, but you'll have considerably less room in which to work.

2. Prepare the Old Faucet for Removal

Turn off the water by rotating the shutoff valves clockwise as far as they will go (if the valves have lever handles, turn the levers so they are perpendicular to the water pipes). Unscrew each water supply hose from the shutoff valve using tongue-and-groove pliers. You can also unscrew the hoses from the faucet supply tubes if they are easy to reach. If not, you can do this after you remove the old faucet.

Unscrew the faucet mounting nuts using a basin wrench. Some mounting systems use screws, and you need a Phillips screwdriver to remove them, so check carefully. If the nuts or screws are fused and won't turn, try heating them with a hair dryer on high heat to loosen the corrosion. If that doesn't work, wait for the nuts to cool and then apply liberal amounts of penetrating spray lubricant. Wait 10 minutes, try to loosen the nuts and repeat if necessary.

3. Pull Out the Faucet and Clean Up

Pull the old faucet straight up until the mounting posts clear the holes and then remove it. Some faucets have copper supply tubes that terminate in 1/2-inch brass fittings, and these can be difficult to force through the holes. The faucet is a goner anyway, so you may want to make your life easier by cutting off the fittings with a hacksaw or a tubing cutter.

Scrape old plumbers' putty and caulk from around the sink or countertop holes using a putty knife. After you've removed as much as you can, clean up the residue with dish soap and water or a rag or sponge moistened with a solvent, such as acetone or denatured alcohol.

4. Drop In the New Faucet

Fit the gasket around the base of the faucet if one is included. If there's no gasket or escutcheon plate, which is unusual, pack the faucet base with plumbers' putty. Alternatively, you can seal the faucet to the sink with silicone caulk per the faucet manufacturer's instructions.

Feed the water lines through the holes in the sink deck or countertop, lower the faucet into place and adjust it to be roughly in the position you want it. You can fine-tune the orientation while you're tightening the mounting nuts.

5. Begin Securing the Faucet From Underneath

Use whatever mounting nuts or fasteners that came with the faucet to secure it to the sink. Some models have a plate that slides up along the supply tubes, which is then screwed to the base of the faucet with a screwdriver. More common are faucets that have nuts that are screwed onto the faucet's threaded posts and tightened with a basin wrench. Some manufacturers include a long socket wrench sized for the nuts, which eliminates the need for a basin wrench.

6. Center the Faucet and Tighten It

Tighten the mounting nuts or brackets until the faucet is slightly difficult to move and then adjust it to be in the exact position you want before tightening it completely. It isn't a bad idea to get a helper to hold the faucet to prevent it from slipping out of position at the last moment.

7. Connect All Included Hoses

If your new kitchen faucet has a side sprayer or it's a pullout model with a sprayer in the spout, it has a sprayer hose. Widespread models with handles separated from the spout also have hoses. Connect these hoses now. They often come with quick-connect fittings that you simply push together while holding down a tab or button on the female connector, or they may use threaded compression fittings. If the latter, tighten the fittings with two pairs of tongue-and-groove pliers — one to hold the male side of the fitting and one for the female side.

You usually don't use thread-seal tape when connecting compression fittings, but check the manufacturer's instructions and use it if recommended. If you're installing a pullout faucet, a weight will be supplied in the box to retract the sprayer. Clip this to the sprayer hose after you've finished making connections.

8. Connect the Supply Hoses

Wrap thread-seal tape around the threaded supply posts or male-threaded connectors on the faucet and then screw a flexible supply hose connector onto each one. Do the same to attach each hose to one of the shutoff valves, wrapping thread-seal tape around the valve threads. Tighten each connector with tongue-and-groove pliers. Turn on the water by opening the shutoff valves all the way.

9. Turn on the Faucet and Check for Leaks

Unscrew the faucet aerator, open the hot side of the faucet and let the water run for a minute to flush debris out of the water line. Turn off the hot water and repeat with the cold water. Reinstall the aerator, close the faucet and check for leaks from any of the flexible supply-hose connectors. Tighten any connection that leaks.

10. Finish the Job

If you used plumbers' putty to seal the faucet base to the sink deck, some of it probably oozed out when you tightened the mounting nuts. The easiest way to remove this is to scrape and rub it off with your finger and then remove any residue with a paper towel. Reinstall the P-trap and/or garbage disposal as applicable.

Stephen Paul for Hunker

Some faucets are designed to open when you wave your hand, and some open and close when you touch the spout. Each of these comes with proprietary parts that may include battery packs, wires and electrical insulators. On some models, the valve assembly and spout are separated and must be connected with tubes supplied with the installation kit. Extra procedures may include screwing a battery pack to the underside of the cabinet and connecting it to the faucet controls.

There's no general procedure for installing such specialty equipment. It's crucial to read the instructions that come with the faucet and follow them closely. The instructions are sometimes technical and difficult to understand, so don't hesitate to get professional help if you feel overwhelmed.