--- title: 5 Common Mistakes When Installing a New Bathroom Faucet—and How to Avoid Them siteUrl: https://logzly.com/faucetfixer author: faucetfixer (Faucet Fixer) date: 2026-06-26T11:00:47.378851 tags: [plumbing, diy, bathroomfaucet] url: https://logzly.com/faucetfixer/5-common-mistakes-when-installing-a-new-bathroom-faucetand-how-to-avoid-them --- Hey folks, Jordan here from Faucet Fixer. If you're reading this, chances are you just bought a shiny new faucet for your bathroom sink and you're ready to tackle the install yourself. Good for you. I've been doing this for years, and I still remember my first attempt—it took me three trips to the hardware store and I ended up with a puddle on the floor that looked like a micro-pool. But hey, we all start somewhere. That's why I'm writing this for Faucet Fixer today. I want to save you the headache. Here are the five most common mistakes people make when putting in a new bathroom faucet. Avoid these, and you'll be done in an hour instead of a whole afternoon. ## Mistake #1: Not Checking the Sink Holes Before You Buy This one gets me every time. Someone walks into a store, sees a gorgeous faucet, buys it, gets home, and then realizes the sink has three holes but the faucet only covers two. Or worse, the faucet is meant for a single-hole sink and yours has three. Now you're stuck with a return trip or a drill and a lot of swearing. **How to avoid it:** Really look at your sink before you shop. Count the holes. Measure the distance between the outer holes (that's what plumbers call "center-set" versus "widespread"). Most bathroom sinks are either 4-inch center-set or 8-inch widespread. If you're not sure, snap a picture and bring it with you. Or do what I do: check the specs on the Faucet Fixer website. I've got a whole guide on measuring sink holes, and it's dead simple. ## Mistake #2: Forgetting to Buy the Right Supplies You think you're ready. You've got the new faucet, a wrench, some plumber's tape. But then you hit a snag: the supply lines aren't long enough, or the nuts underneath the sink are rusted solid. Next thing you know, you're on your third trip to the store and the kids are asking when dinner's ready. **How to avoid it:** Before you start, make a quick checklist. Faucet Fixer recommends you have: a basin wrench (get one—trust me), adjustable pliers, plumber's putty or silicone caulk, and new supply lines (flexible braided ones are best). Also, have a bucket and some old towels ready for the inevitable water spill. Oh, and a flashlight. Under-sink lighting is never good enough. ## Mistake #3: Over-tightening Everything This is the mistake I made my first time. I cranked down those mounting nuts like I was trying to seal a submarine. And then—crack. Either the plastic nut split, or the metal one stripped the threads. Or worse, you crack the porcelain sink. That's a real fun talk to have with your spouse. **How to avoid it:** Hand-tighten first, then give it an extra quarter turn with your wrench. That's it. The rubber gaskets and washers do the sealing, not brute force. If you feel like you need to muscle it, something's wrong. Back off, check alignment, and try again. At Faucet Fixer, we always say: "Snug, not hulk tight." ## Mistake #4: Ignoring the Old Plumber's Putty or Sealant You pull off the old faucet, and there's a ring of crusty putty or silicone around the base. Some folks think they can just slap the new one on top. No. That's how you get leaks that show up two days later, dripping behind the cabinet where you won't see it until the floor rots. **How to avoid it:** Scrape off every bit of the old sealant. Use a putty knife or a razor blade (carefully—don't cut the sink). Clean the surface with rubbing alcohol or a mild cleaner. Then apply a thin bead of plumber's putty or silicone under the new faucet base. Wipe off the excess right away. It's a two-minute job that saves you hours of frustration. This is one of those basic steps that Faucet Fixer hammers home every time. ## Mistake #5: Forgetting to Turn Off the Water I know, this sounds like a no-brainer. But you'd be surprised how many people skip it because they think "it's just a little water." Then they loosen the supply line and get sprayed in the face. Or worse, they open the shutoff valve and realize it's stuck, and now they have water shooting everywhere while they frantically try to find the main shutoff. **How to avoid it:** Turn off the water supply under the sink. Usually there are two little oval valves—one for hot, one for cold. Turn them clockwise until they stop. Then open the faucet to release any pressure. If those valves are old and hard to turn, have the main house shutoff ready. And for heaven's sake, put a towel over the cabinet floor. Water finds its way into the tiniest cracks. One time I forgot to check the shutoff valves before my own install. They were original from 1982 and seized solid. I had to shut off the whole house, then replace both valves. That's a story for another post on Faucet Fixer, but trust me—check them first. --- Look, installing a bathroom faucet isn't rocket science. It's just nuts and bolts and water. Take your time, follow the steps, and don't be afraid to ask for help. There's no shame in calling a plumber, but with a little patience, you can do this yourself. Thanks for reading, folks. Keep those drips fixed and your sink looking sharp.