How Do You Install a Bathtub Faucet With Shower the Right Way in 2026?

Learning how to install a bathtub faucet with shower is one of the more satisfying bathroom projects you can tackle yourself, but it’s also the one people underestimate the most. The visible parts — the spout, the handle, the shower head — take minutes. The real work is the valve behind the wall and the connections that feed it. This guide walks you through the whole job the way a plumber actually does it, in plain language, with the numbers and specs that matter so you don’t end up chasing a leak after the tile is back up.

Whether you’re upgrading a plain tub to a tub-and-shower combo or swapping a tired old set, the process is the same at its core: a single valve body controls hot and cold, a diverter sends water up to the shower or down to the tub spout, and everything has to be sealed and secured before you trust it. Let’s break it down.

What Parts Do You Actually Need to Install a Tub Faucet With a Shower?

You need a tub-and-shower valve body, trim (handle, spout, and shower head/arm), a riser pipe, a drop-ear elbow for the shower arm, and the fittings and sealant to connect it all. That’s the short list — here’s what each piece does and why it matters.

• Shower/tub valve body: The brass heart of the system, buried in the wall. Modern code (and most local inspectors) require a pressure-balancing or thermostatic valve so a flushed toilet doesn’t scald you in the shower.
• Trim kit: The handle, escutcheon (wall plate), and spout you actually see and touch. Trim must match the valve brand and series — this is where most DIY mistakes happen.
• Tub spout with diverter: The spout that pulls up to divert water to the shower head.
• Riser pipe: The vertical ½-inch pipe carrying water from the valve up to the shower arm, typically ending 72–80 inches off the floor.
• Drop-ear elbow: A threaded fitting anchored to a wood brace that holds the shower arm firm.
• Consumables: PTFE thread-seal tape, plumber’s putty or silicone, and either solder/flux (copper), crimp rings (PEX), or push-to-connect fittings.

One planning note before you buy: confirm whether you want a single-handle or two/three-handle system. Single-handle pressure-balance valves are the modern default and the easiest to live with. If you’re weighing shower components separately, our handheld shower head kit with valve buying guide breaks down how the valve and head are matched as a set.

Can You Install a Bathtub Faucet With Shower Yourself, or Do You Need a Plumber?

You can absolutely DIY this if you’re only swapping trim or replacing a valve in an accessible wall — a competent DIYer with basic tools can do it in an afternoon. You should call a licensed plumber if the job involves soldering copper in a finished wall, moving supply lines, or if your local code requires a permit and inspection for valve replacement.

Here’s the honest dividing line. If the back of your shower wall is open (a closet or unfinished space behind it), the job is far friendlier because you can reach the connections without demolishing tile. If everything is sealed behind finished tile, you’re either cutting an access panel, working through the valve opening, or accepting some tile repair. Be realistic about your comfort with water connections — a valve leak inside a wall is expensive and miserable to find later.

If your existing setup is a tub-only faucet and you’re adding a shower, that’s a bigger job than a straight swap because you’re adding the riser and shower arm. For a simpler tub-faucet refresh, our step-by-step walkthrough on how to replace an old tub faucet covers the spout-and-handle side in more depth.

How Do You Install a Bathtub Faucet With Shower Step by Step?

Install a bathtub faucet with shower in this order: shut off water, remove old fixtures, mount the valve body, connect supply and riser lines, install the tub spout and diverter, attach the shower arm and head, then test. Below is the full sequence with the details that keep you out of trouble.

Step 1 — Shut off the water and drain the lines

Turn off the water at the shower’s local shutoffs if you have them, or at the main. Open the tub faucet to drain residual water and relieve pressure. Lay a towel in the tub to protect the finish and catch dropped screws.

Step 2 — Remove the old faucet and handles

Pop off the handle caps, unscrew the handles, and unthread the old tub spout (twist counterclockwise — some slide onto a copper stub and are held by a set screw underneath). Remove the escutcheon plates. If you’re keeping the old valve, skip to trim installation; if you’re replacing it, expose the valve body.

Step 3 — Install the valve body

Mount the new pressure-balancing valve so the “up” arrow faces the ceiling and the marked depth line sits flush with your finished wall surface — this is critical, because a valve set too deep or too proud will fight your trim. Secure it to a cross-brace between the studs.

Step 4 — Connect hot, cold, spout, and riser

The valve has four ports: hot in (usually left), cold in (right), a bottom port to the tub spout, and a top port to the shower riser. Connect each using your pipe method — sweat-soldered copper, crimped PEX, or push-fit. Run the ½-inch riser up to a drop-ear elbow braced at 74–78 inches. Wrap all threaded joints with PTFE tape.

Step 5 — Install the tub spout and shower arm

Thread the tub spout onto its nipple (or clamp the slip-fit type onto the copper stub), sealing threads with tape and the wall gap with silicone. Screw the shower arm into the drop-ear elbow, then hand-tighten the shower head. The tub spout must sit far enough from the wall that its diverter can pull cleanly — if yours is too short, our guide on how to install a tub spout extension solves that exact problem.

Step 6 — Install trim and test

Slide on the escutcheon, install the cartridge (if not pre-installed), attach the handle. Turn the water back on slowly and check every connection for weeping. Run the tub, pull the diverter, confirm water shifts fully to the shower with no dribble from the spout. Only after a clean pressure test do you close up the wall.

What’s the Difference Between the Valve Types — Which One Should You Buy?

For almost every home, buy a single-handle pressure-balancing valve — it’s code-compliant, affordable, and simple. Step up to a thermostatic valve only if you want precise, set-and-forget temperature or a multi-outlet shower. Here’s how the common options compare.

A quick word on matching: valve bodies and trim are brand- and series-specific. A trim kit from one line usually will not fit another manufacturer’s rough-in valve. Before you buy anything, confirm the valve and trim are a matched set — the same compatibility logic we cover in how to check faucet compatibility before buying applies directly here and saves a lot of returns.

How High Should You Mount the Tub Spout, Valve, and Shower Head?

Standard rough-in heights are: tub spout about 4 inches above the tub rim, the valve/handle at roughly 28 inches off the tub floor (or 8–12 inches above the spout), and the shower head at 72–80 inches from the floor. These are guidelines, not gospel — tall households routinely raise the shower arm to 80 inches or more.

The shower head height in particular is worth getting right, because moving it later means opening the wall again. If your household spans a range of heights, a handheld on a slide bar is the flexible answer; our handheld shower head mounting height guide gives exact numbers for fixed and adjustable setups. A few rules of thumb:

• Tub spout: High enough to clear the tub rim with an air gap — never submerged, or you risk back-siphonage.
• Valve: Reachable from outside the tub so you can start the water without standing under a cold blast.
• Shower head: At least 6–8 inches above the tallest user’s head so the spray falls, not sprays sideways.

What Mistakes Cause Leaks After Installing a Tub-and-Shower Faucet?

The top leak causes are over-tightening plastic fittings, skipping thread-seal tape, setting the valve at the wrong depth, and closing the wall before pressure-testing. Every one of these is preventable in the minutes before you finish the job.

1. No leak test under pressure: Always run the system and inspect all joints for at least 10–15 minutes before tiling over anything.
2. Cross-threaded or over-torqued connections: Cracked brass and stripped plastic both weep slowly. Snug, don’t gorilla-tighten.
3. Wrong valve depth: If the escutcheon won’t sit flush or the cartridge binds, the valve is set too deep or shallow.
4. Diverter that won’t seal: Water dribbling from the spout while showering usually means a worn spout diverter or a spout mounted too close to the wall.
5. Forgotten PTFE tape or putty: Threaded metal joints need sealant; the escutcheon-to-wall gap needs silicone to keep water out of the wall.

If you finish the install and something feels loose or rattly, don’t ignore it — a wobbly handle or spout is often just a set screw, and our step-by-step guide to tightening a wobbly faucet covers the quick fixes before they turn into leaks.

Author Note & Why Trust This Guide

This guide was written by the KES product and installation team, drawing on hands-on testing of tub-and-shower valves and trim across thousands of real bathroom installations. At kesfaucet, we design and manufacture faucets and shower systems built to cUPC/NSF standards, pressure-test every valve body before it ships, and back our tub-and-shower fixtures with a limited lifetime warranty on the finish and function. Our recommendations here reflect the same rough-in and pressure-balance requirements that plumbing inspectors check on the job — not shortcuts.

A final practical tip: buy your valve, trim, spout, and shower head as a coordinated set from one line whenever you can. It eliminates compatibility guesswork, keeps the finish consistent, and means one warranty covers the whole system. That’s the difference between a faucet you install once and one you’re troubleshooting every season.

FAQ

How long does it take to install a bathtub faucet with shower?

Plan on 3–5 hours for a straightforward trim-and-valve swap in an accessible wall, and a full day if you’re adding a shower to a tub-only setup, moving plumbing, or working behind finished tile. Most of the time goes into the valve connections and the leak test, not the visible fixtures.

Do I need to open the wall to replace a tub-and-shower faucet?

Not always. If you’re only replacing the trim and cartridge, you can work through the existing valve opening. You’ll need wall access if you’re replacing the valve body itself, changing pipe connections, or the valve is corroded. An access panel behind the wall — from a closet, for example — is the easiest way to reach connections without cutting tile.

Can I use my old trim with a new valve (or vice versa)?

Usually not. Trim kits are engineered for a specific valve series from the same manufacturer, so mixing brands rarely works and can leak or bind. Always confirm the valve and trim are a matched set before buying, and check the rough-in depth against your wall.

Why does water still come out of the tub spout when the shower is on?

That’s a diverter problem. Either the tub spout’s internal diverter is worn and no longer sealing, or the spout sits too close to the wall to pull up fully. Replacing the spout usually fixes it; if the spout is too short for a clean diverter action, a spout extension solves it.

What type of shower valve is required by code in 2026?

Most jurisdictions require an anti-scald valve — either pressure-balancing or thermostatic — for any tub-shower combo. A basic pressure-balancing single-handle valve satisfies code in the vast majority of homes and is the affordable, DIY-friendly default. Check your local building department if a permit is required for valve replacement.

How do I know if my new valve is installed at the right depth?

Manufacturers mark a “finished wall” line or provide a plaster guard on the valve body. The finished tile surface should line up with that mark. If the escutcheon won’t sit flush against the wall or the cartridge is hard to seat, the valve is set too deep or too shallow and needs adjusting before you tile.