How to Install SharkBite Fittings on PEX: A Contractor’s Field Checklist

I’m a plumbing contractor who’s been handling service and remodel work for nine years. I’ve personally made—and documented—more than 20 installation mistakes, totaling roughly $4,000 in wasted material and rework. I now maintain our crew’s checklist so the next person doesn’t have to learn the same way I did.

When I first started using SharkBite fittings on PEX, I assumed push-to-connect meant foolproof. It doesn’t. It’s a solid system if you respect the prep. That lesson cost me a finished basement wall in 2019.

This is the checklist I run now. If you’re here for the plastic insert question, I’ll get to it. But the steps around it matter more.

How to Install SharkBite Fittings on PEX

Before I touch a fitting, I confirm the product carries a listing mark I can point to—for SharkBite that usually means ASSE 1061 and NSF/ANSI 61. A listing is not a blank check. It means the fitting works when you install it exactly the way the manufacturer specifies.

Here’s the order I use:

1. Confirm the pipe type. Read the printing on the PEX. It should say PEX, and it should indicate the standard. If you grab the wrong pipe, the connection is out of spec.
2. Cut it square. A PEX cutter is the right tool. A hacksaw or utility knife leaves ridges and a rough end. The grab ring needs a round, square surface to bite into.
3. Deburr the inside and outside. This is the step I used to skip, and it’s the step that tears O-rings. A tiny plastic burr can catch the O-ring when the pipe slides in. Deburring takes ten seconds.
4. Mark the depth. SharkBite sells a depth gauge; if you don’t have one, use the depth chart in the instructions and make a small mark with a marker. After you push the pipe in, the fitting’s edge should line up with that mark.
5. Push straight in. The fitting is designed for a straight push, not a wiggle or an angle.
6. Tug on it. The pull test is the fastest check for a bad seat. If the pipe comes out or moves, cut the pipe back and start again.
7. Pressure test. Before you close up a wall, basement, or vanity cabinet, test the line. Last fall, I almost closed an access panel without testing. The test caught a 1/2-inch fitting that wasn’t fully seated. That could have been a $400 repair instead of a 30-minute fix.

Do You Need the Plastic Insert for SharkBite Fittings?

The short answer is no—not for SharkBite push-to-connect fittings on standard PEX. The manufacturer’s current installation instructions don’t require a separate plastic insert for PEX.

This confuses people because other PEX connection systems do require a stiffener. A plastic insert is meant to keep soft tubing from collapsing under compression. SharkBite push-to-connect fittings are designed differently. The grab ring and O-ring are in specific positions, and the pipe needs to reach a specific depth. If you add a plastic insert that isn’t specified, it can stop the pipe too early or hold the collar off center.

So the question everyone asks is about the insert. The question that matters more is: “Was the pipe cut square, deburred, and pushed to the marked depth?”

Tool Notes From the Field

Fittings don’t install themselves. Here are three tools I replaced after using bad ones for too long. Not an ad, just lessons.

Hex Key Set Review: What I Looked For

If you’re reading a hex key set review, you’ve probably got a stripped set screw in your future—or your past. I learned the hard way with a cheap folding set. It stripped the set screw on a sink stop valve and turned a 10-minute repair into an hour of drilling and tapping.

What do I look for now? SAE and metric sizes in one set, chamfered tips, and a ball-end on the long arm for awkward angles. Color coding helps, but it’s not the main event. The rule I repeat to the guys on our team: ball-end for speed, straight end for final torque. That one rule will save you more parts than any premium brand.

If a hex key set review mentions the case or the color but not the tip geometry, keep reading.

TE 17 Hammer Drill: Overkill Until It Isn’t

I avoided buying a real rotary hammer for years. I told myself a corded hammer drill was enough. Then I had to drill a dozen anchor holes in a poured foundation to mount a pump bracket. My drill bit got hot, the holes were shallow, and my arms felt like jelly.

A friend handed me his TE 17 hammer drill. The TE 17 is a compact SDS-Plus rotary hammer, not a heavy demolition tool. It drilled the same holes in almost no time and didn’t bounce around like a paint shaker.

Is it worth it if you only drill concrete once a year? Probably not. But if your work includes PEX lines through foundation walls, concrete anchors for pump brackets, or valve boxes, the TE 17 is the class of tool that makes the job honest. I bought one after the second foundation job and haven’t looked back.

What Is the Best Type of Nail Gun for Trim?

For 90 percent of interior trim, my answer is a 16-gauge straight finish nailer. It handles baseboard, casing, and door stops without splitting standard pine. It holds the trim tight enough to get a clean joint. An 18-gauge brad nailer is better for shoe molding and thin profiles. A 15-gauge angled finish nailer is better for thick, pre-finished jambs where you need more holding power.

Why is a nail gun in a plumbing article? Because after a plumbing remodel, the baseboard often comes off. If it’s going back on, the nail gun is the difference between a clean hole and a split casing. I use a pneumatic 16-gauge because I already have a compressor. If you’re on a small crew, a cordless 16-gauge finish nailer works just as well.

The Last 10%

The industry has changed. Push-fit fittings that were new to me in 2017 are now a standard way to make PEX connections. What was common practice then—and what some online guides still show—is not always what the current instructions say. This is an industry that keeps evolving, and the fundamentals are the same: clean pipe, full depth, pressure test.

If I had to write a final checklist, it would be this:

• Read the current installation instructions, not last year’s.
• Cut, deburr, mark, push, pull, test.
• Don’t add a plastic insert to a SharkBite push-fit fitting on PEX unless the manufacturer says to.
• Use the straight end of a hex wrench for final torque.
• Grab a 16-gauge finish nailer before you reinstall the trim.

That’s it. Most of my $4,000 in mistakes came from skipping one of those steps. A checklist isn’t flashy. It’s just cheaper than the alternative.