It might seem intimidating if you’ve never done it before, but replacing a sink is a relatively straightforward task for the home DIYer. This is something you can easily do in one day, even if you have limited experience with plumbing. It’s hard to give an estimated time, because you may or may not need to make hardware store runs. Still, it’s all fairly straightforward! You should be able to get it done in either a morning or an afternoon.
The toughest part comes first: making space to access the old fittings, and dealing with rusted or corroded fittings. Installation is usually a breeze, as long as you’re careful to take your time and follow the instructions provided with your new fixture.
Here’s how to get the job done:
Be sure you’ve got a high-quality replacement fixture. Don’t cheap out and get something made with crappy plastic components. You want something made mostly or completely from metal components, with a reliable valve and fittings that won’t let you down. Find our reviews and recommendations for the best kitchen faucets on our homepage!
Pick up any components you know you’ll need
Before starting, make sure you have an open-ended adjustable wrench handy! You’ll also need some fine-grit sandpaper. Pick that up at the hardware store if you don’t have any hanging around.
Check for shutoff valves under the sink. They’ll be on the feeder (supply) lines going to your faucet. If you’ve had yours installed relatively recently, there should be shutoff valves. Older setups and even some newer ones may not have these valves. You really want them, since they make installing and modifying plumbing fixtures infinitely easier.
If you don’t see any, add a set to your shopping list. You want compression-fit components, nothing you have to solder. This should be a really simple addition for you to make. If you already have shutoff valves, be sure to check them by shutting them off and opening the taps. If you see any dripping, plan to replace them. Most people have 1/2” copper supply pipes under the sink, so buy valves to match (or match whatever pipes you have).
As long as you’re making some modifications anyway, you should also buy some new supply tubes while you’re at the hardware store. Fitting valves or making any other modifications to rigid copper is a real pain, so save yourself the trouble now and in future by getting some flexible, stainless-steel lined tubing. You can easily shape this around any obstacles you might have, and if it’s stainless-steel lined it won’t kink or break quickly like plastic.
Get yourself a basin wrench, if you’re replacing an older faucet. All new faucets (and most recent fixtures) use simple wing nuts. So, if you’re replacing something relatively recent, no need to grab one of these. Basin wrenches are the only way to loosen older faster types, though.
Don’t try to do this project when the hardware store is closed! You want to be able to quickly go and buy any parts you discover you need. It’s good to be aware that things will typically come up during the process, no matter how well you plan ahead.
If you’re going to be modifying copper piping, you should grab a tubing-cutter if you don’t already have one. You could theoretically use a hacksaw, but they’re tricky to maneuver in tight quarters.
Get yourself situated
Clear out the space under your sink. You want as easy access as possible to all the fittings and piping under the sink. Find something to kneel or lay on, since it’s easy to get uncomfortable doing this task.
Take a picture of everything on your phone
This is just plain common sense before you take apart and reassemble anything around the house. Even if you’re going to be doing modifications, you ought to take a picture so you know how to put it all back together.
Make sure you’re working with dry plumbing
It’s impossible to do any of this with water running through your pipes, so make sure that’s taken care of. Turn off your supply valves, if you have them. If you don’t have them, shut off the main water supply until you’ve fitted them. Let your faucet run to bleed out any water in the lines.
Take things apart
Remove the drain lines from the old faucet. You can go ahead and get the P-trap out of the way while you work, too. It’ll give you a lot more space to work. Taking these things apart is essential if they block access, but you may be able to skip it if you have a roomy space to work in. There will often be some excess water in the P-trap, so have a bucket handy to catch it! You’ll also want to disconnect the supply lines at this point, wherever they attach to the faucet fittings.
Remove the old faucet
Use your basin wrench to loosen the old faucet, or loosen the wing nuts by hand if it’s a relatively new fixture. Lift it out, taking its supply line sections with it. Clean the mounting area of the sink/countertop so that your new fixture can be caulked easily for a watertight seal.
Installing a new faucet
Always follow instructions! If the instructions tell you to do something other than what we’ve outlined, go with the manufacturer’s advice.
Do any pre-assembly tasks
In some cases, you’ll need to put components together before you install them. Sometimes, everything comes pre-assembled. Check your instructions.
Lower the fixture into place
Place the faucet, flange, or escutcheon over the opening (which of these you have will depend on the specific model you’ve bought). The supply fittings on the new fixture should be sticking down below the countertop.
Make sure it’s fitted in the right direction (it’s easier to mess this up than you’d think) by testing the knobs and range of motion for the spout.
Thread the new supply lines through the faucet mounting nut, then push the nut up flush with the bottom of the opening. Then, tighten the faucet mounting nut (this is usually done with a special tool, provided with the fixture).
Tighten the flange nuts, if you’re using one. Tighten them as much as possible by hand, since it’s a pain to use wrenches in this tight space!
Replace/add valves and supply lines
Fit your shutoff valves on one end of your new, flexible supply tubing. Then, attach the other end to your new faucet. You’ll have to do this twice, once for the hot water and once for the cold (this is also the time to hook up the spray hose). See how far down the old copper piping the new tubes reach. You want to line each up for a good approximation.
Cut rigid copper piping just above where the new valves line up, and clean the cut end with fine-grit sandpaper. Then, use the compression-fit component to lock the valve fitting onto the old copper piping.
Reassemble everything else
Once it’s all put together the way it was originally (aside from your modifications), switch the shutoff valves to the open position. This is your chance to check everything for leaks! If it’s all leak-free and works as it should, congrats! You’ve saved yourself a heck of a lot of money and achieved something pretty darn handy.
Don’t get aggressive with sticky or corroded fittings. You don’t want to risk breaking them and being stuck with an even bigger mess. Take your time, and use WD-40 liberally if you need to.
If you simply can’t get the old faucet loose, lift out the sink basin. It’s quite simple to do: just loosen any nuts attaching it to the countertop. If there aren’t any, get a flathead screwdriver under the rim and lift it out by loosening the caulk. You can easily reset a sink in 10 minutes. Taking it out will give you much more latitude to work on the pesky fittings!
Run your faucet for a few minutes when you’ve finished. You want to know if you’ve done a good job attaching everything, so give leaks a chance to show themselves.
Remember to caulk under the escutcheon/flange/faucet!