How to replace a shower head in about fifteen minutes

What you need, and what you do not

You need: one adjustable wrench, a roll of PTFE tape (also sold as plumber’s tape or thread seal tape, and it costs about a dollar), a rag, and an old toothbrush. That is the entire list.

You do not need: to turn off the water at the main. The shower’s own mixer is already closed, so the pipe is not under pressure at the arm. Some trapped water will run out when the old head comes off, which is why the rag is on the list.

You also do not need a plumber, a permit, or your landlord’s permission. This is the most reversible change you can make to a bathroom — see what you can change in a rental bathroom for where the actual line sits.

The tape direction, because this is the step people get wrong

PTFE tape seals a threaded joint by filling the tiny spiral gap between the two sets of threads. For that to work it has to stay in place while the head screws on.

Hold the shower arm and look straight into its open end. The new head will screw on clockwise from that view, so wrap the tape clockwise too. The head then turns with the tape and beds it into the threads. Wrap it anticlockwise and the head unwinds the tape as it goes on, bunching it up at the end of the thread where it does nothing at all — and then the joint drips and you assume you needed to tighten harder, which is how threads get damaged.

Three to four layers is right. One is not enough to seal; eight makes the head hard to start and can split a plastic collar.

The five things that go wrong, and what to do

The old head will not budge. Almost always corrosion in the joint. Hold the arm firmly with a cloth-wrapped hand or a second wrench so you are not twisting the pipe inside the wall, and increase force gradually. If it still will not move, wrap the joint in a vinegar-soaked cloth for an hour and try again. Never lever against the tile.

The shower arm turns instead of the head. Stop immediately. The arm threads into a fitting inside the wall, and unscrewing that fitting is the one way this job becomes a real repair. Hold the arm still and turn only the head.

It drips at the joint afterwards. A quarter turn more first. If it still drips, take it off, remove every scrap of tape, and start again — almost always the tape was wrapped the wrong way or old tape was left underneath.

The new head is loose but will not go further. There is debris on the threads or the tape has bunched. Off, clean, re-tape.

The spray is weak with a brand-new head. The head is not the problem: the restriction is upstream, in the arm or the supply. The low-pressure page covers what to check.

While the head is off, look at the arm

You will not get a better look at the shower arm than in the two minutes it is bare. Two things are worth checking.

Are the threads clean and undamaged? Crushed or corroded threads are why some joints never seal properly, and an arm is an inexpensive part to replace while you are already here.

Is the arm the right length and angle for you? Height and reach are set by the arm, not the head, and swapping it is the same kind of threaded job. If you are tall and the water hits your shoulders, that is an arm problem — the shower arm explainer covers it.

Keep the old head

Put it in a bag with the leftover tape and label it. If you rent, that bag is your deposit: five minutes on move-out day and the bathroom is exactly as you found it, with your new head coming to the next place. If you own, it is the spare that saves you an evening when something eventually fails.