How long does it take to fit a new tap?

For a straightforward like-for-like swap with existing flexible tails and working isolation valves, most confident DIYers manage it in around one to two hours, including testing for leaks afterwards. Add extra time if you need to source a basin wrench, if access under the sink is tight, or if it's your first time doing the job.

Do I need to turn off my whole house's water supply to fit a tap?

Not usually. Most modern kitchens and bathrooms have individual isolation valves on the hot and cold pipes feeding each tap, letting you shut off just that supply. If your setup doesn't have these fitted, you'll need to use the main stopcock instead, which cuts water to the whole house while you work. It's worth fitting isolation valves while you're already under there if they're missing.

What is PTFE tape and do I really need it?

PTFE tape is a thin, white plumber's tape wrapped around threaded pipe joints to help create a watertight seal. It's inexpensive and worth using on every threaded connection during a tap installation, since it significantly reduces the chance of a slow leak developing at a joint over the following days or weeks.

Can overtightening a tap damage my sink?

Yes, and it's one of the most common mistakes in a DIY tap installation. Composite and ceramic sinks in particular can crack if the fixing nut underneath is tightened too aggressively. Firm and snug, checked by hand, is enough; you shouldn't need to put your full weight behind a spanner.

Why is water still dripping from the tap after I turned the water off?

This is normal and expected. There's always some water left in the pipe between the isolation valve and the tap itself, and opening the tap after isolating the supply lets that residual water drain out before you start work. If water keeps flowing steadily rather than trickling out and stopping, your isolation valve may not be fully closed or may be faulty.

Do I need plumber's putty as well as PTFE tape?

Not usually on a modern deck-mounted tap. PTFE tape seals the threaded connections between the tails and the isolation valves, while the tap base itself normally seals against the sink with a rubber washer supplied in the box. Plumber's putty or a bead of silicone sealant only comes into play if your tap doesn't include that washer, as a substitute for bedding the base watertight.

What if my new tap's tails don't match my isolation valves?

Most modern flexible tails use a standard fitting that matches standard UK isolation valves, so this is uncommon on a like-for-like swap. If they genuinely don't match, usually on an imported or unusual tap, you'll need an adapter or a replacement isolation valve in the correct size rather than forcing an ill-fitting joint, which is unlikely to seal properly. Our guide on tap connection sizes covers the fittings you're likely to come across.

How do I know if I need a blanking plate?

You need one whenever your new tap uses fewer holes than your sink or worktop has, most commonly when switching from a two or three hole set-up to a single hole monobloc tap. Measure your existing holes and check the new tap's specification before buying so you can order a matching blanking plate at the same time, rather than finding out mid-job.

Home/Guides/How to Install a Tap Yourself

Installation

How to Install a Tap Yourself

A step-by-step walkthrough for anyone reasonably confident with basic DIY, covering the tools you need and when to call a plumber instead

Thomas RichardEditor, The Tap Guide

Updated 13 August 2026 · 6 min read

In this article

Before you start
Tools and materials you'll need
Step 1: Turn off the water supply
Step 2: Remove the old tap
Step 3: Check everything is compatible
Step 4: Fit the new tap
Step 5: Connect and test
Kitchen tap vs bathroom tap: does the method differ?
Common mistakes worth avoiding
When to call a plumber instead

Fitting a new tap is one of the more approachable plumbing jobs for a confident DIYer, provided you take your time and don't skip the step where you actually check everything for leaks before walking away. Here's how it goes from start to finish.

This guide covers a standard deck-mounted kitchen or basin tap, the kind that sits through the sink or worktop with flexible tails running down to isolation valves underneath, which covers the vast majority of straightforward swaps. Wall-mounted taps and bath fillers use a different fitting method and aren't covered here.

If your existing pipework is old, corroded, or you're changing from a two hole tap to a monobloc (or vice versa), this job gets more involved and it's worth getting a plumber in. The steps below assume a straightforward like-for-like tap swap with existing flexible tails.

Before you start

Clear out the cupboard under the sink and lay down an old towel or two, both to catch drips and to give your knees something better than a bare cabinet floor. A head torch is worth the small investment if you're doing more than one tap, since holding a torch and a spanner at the same time under a sink gets old fast.

Check your new tap's tails against what's already there before you start. Most modern taps come with flexible tails ending in a standard connection that matches UK isolation valves, but it's worth confirming the fitting genuinely matches, particularly on an imported or budget tap, rather than finding out halfway through the job. Our guide on tap connection sizes covers the different fittings you might come across.

Tools and materials you'll need

Adjustable spanner and a basin wrench (a long, angled spanner designed for tight spaces under sinks)
PTFE tape (thin white plumber's tape for sealing threaded joints)
Silicone sealant, for bedding the tap base if your tap doesn't come with its own rubber sealing washer
A bucket or old towels for the inevitable drips
Your new tap, plus any flexible tails or fittings it requires
A torch, since under-sink cabinets are rarely well lit

Step 1: Turn off the water supply

Find the isolation valves for the hot and cold supply, usually small quarter-turn valves on the pipes just below the sink. Turn both to the off position (the slot should sit across the pipe, not in line with it).

If your set-up doesn't have isolation valves fitted, you'll need to turn off the water at the main stopcock instead. Once off, open the tap fully to release any remaining pressure and let it drain before you continue.

Step 2: Remove the old tap

Working underneath the sink, disconnect the flexible tails from the isolation valves first, then loosen the large fixing nut holding the tap body to the sink or worktop. This is where a basin wrench proves its worth, as the nut is often in an awkward spot behind the bowl.

Once loose, the old tap should lift out from above. Clean up any old sealant or residue from the sink surface before fitting the new one.

If the fixing nut has seized solid, usually from years of limescale and corrosion, don't force it with excessive strength since you risk snapping the tap tails or damaging the sink. Penetrating oil left to soak for ten minutes, or gently warming a metal nut with a hot cloth, often frees it up. Our guide on removing an old tap covers seized nuts, stuck putty, and other awkward removals in more detail if yours is proving stubborn.

Step 3: Check everything is compatible

Dry fit the new tap's tails through the sink hole before sealing anything, just to confirm the length and fitting match up with your isolation valves. If your new tap has a different hole configuration (say you're moving from two holes to one), you'll need a blanking plate for any spare hole, available from most plumbing suppliers.

This is also the point to double check your new tap will actually work well on your home's water system. A tap that needs strong mains pressure to perform properly can disappoint on a gravity fed system with a header tank in the loft. Our guide on what flow rate you need covers matching a tap to your plumbing before you're committed to fitting it.

Step 4: Fit the new tap

Feed the tap's tails down through the sink hole from above, adding the sealing washer supplied with the tap between the tap base and the sink surface. If your tap doesn't come with a rubber sealing washer, run a thin bead of silicone sealant around the underside of the tap base instead, to stop water tracking underneath and pooling unseen on the worktop or cabinet below.

From underneath, secure the fixing nut, tightening enough to hold the tap firmly without overtightening and cracking the sink surface, particularly with composite or ceramic sinks. Wrap PTFE tape clockwise around any threaded connections before attaching the tails to the isolation valves, which helps create a watertight seal.

PTFE tape worth a look

VCE PTFE Tape

£3.99 (correct as of August 2026)

A single spool of white PTFE tape from VCE, wound around threaded plumbing joints to help them seal watertight.

We like

Doesn't fray or shred into stray threads as you wind it, and comes off cleanly if you need to redo a joint
Rated to 150 to 200kg/cm² and -190°C to 370°C, comfortably beyond anything a domestic tap connection needs
Snap-on cover keeps the roll from unwinding loose in a toolbox or drawer

Worth checking

Not adhesive on its own, it's a wrap-around thread seal rather than a repair tape, so it only helps at a threaded joint, not a crack or split in a pipe

Material: PTFE (Polytetrafluoroethylene)
Colour: White
Pack contents: 1 spool
Temperature range: -190°C to 370°C
Pressure resistance: 150 to 200kg/cm²
Packaging: Resealable pouch with snap-on roll cover

Specifications above listed by Amazon and may change. Check the current listing before buying. If we've got something wrong, let us know and we'll fix it.

View on Amazon

Step 5: Connect and test

Connect the flexible tails to the correct hot and cold isolation valves, checking you haven't swapped them, then turn the water supply back on slowly. Run the tap for a minute on both hot and cold to clear any air and debris from the new fitting, then check every joint underneath for drips, using a dry piece of tissue paper to spot the smallest leaks that aren't obviously visible. Tighten slightly if needed and recheck after a few minutes.

If you used silicone sealant around the base, leave it to cure for the time stated on the tube, usually 24 hours, before running the tap fully or letting the area get wet, so it has a proper chance to bond.

Kitchen tap vs bathroom tap: does the method differ?

The steps above apply equally to a kitchen sink tap and a bathroom basin tap, since both are usually deck-mounted with the same flexible tail and isolation valve set-up underneath. The main practical difference is space: a bathroom cabinet or pedestal is often tighter to work in than a kitchen cupboard, so a compact basin wrench earns its keep more here than anywhere else. If you're weighing up which tap to buy in the first place rather than how to fit it, our guides on choosing a kitchen tap and choosing a bathroom tap cover that separately.

Common mistakes worth avoiding

Overtightening the fixing nut. This is one of the most common causes of cracked sinks, particularly composite or ceramic ones. Firm and snug is enough.
Skipping the PTFE tape. Threaded joints without tape are far more likely to weep slowly over the following weeks, which can be harder to spot than an immediate leak.
Swapping hot and cold. Double check which isolation valve is which before connecting, as it's an easy mistake to make and annoying to fix afterwards.
Not bedding the tap base properly. A missing or poorly seated washer, or a skipped bead of silicone, lets water track underneath the tap and pool unseen until it eventually stains or damages the worktop.
Forcing a seized fixing nut. Excessive force risks snapping the tap tails or cracking the sink. Penetrating oil and a bit of patience solve most seized nuts without a fight.
Not testing thoroughly enough. A joint can look dry and still be very slowly weeping. Give it a proper check five or ten minutes after the initial test, not just immediately after turning the water back on.

When to call a plumber instead

If your pipework is old, if you're changing the type or position of the tap significantly, if you can't locate or operate your isolation valves safely, or if anything about the job feels beyond straightforward, it's worth paying for a plumber. A stuck job halfway through, with your water supply off and a family needing the kitchen or bathroom, is far more stressful than the cost of getting it done properly the first time. WaterSafe, the UK-wide search service for approved plumbers, is a good place to find someone qualified in your area. Our guide on what fitting a tap costs breaks down typical plumber charges against the cost of doing it yourself, if you're still weighing up which route makes sense.

Not sure which tap to fit in the first place? Our guide on choosing a kitchen tap and our kitchen tap shortlist are both worth a look before you buy.

Frequently Asked Questions

: For a straightforward like-for-like swap with existing flexible tails and working isolation valves, most confident DIYers manage it in around one to two hours, including testing for leaks afterwards. Add extra time if you need to source a basin wrench, if access under the sink is tight, or if it's your first time doing the job.
: Not usually. Most modern kitchens and bathrooms have individual isolation valves on the hot and cold pipes feeding each tap, letting you shut off just that supply. If your setup doesn't have these fitted, you'll need to use the main stopcock instead, which cuts water to the whole house while you work. It's worth fitting isolation valves while you're already under there if they're missing.
: PTFE tape is a thin, white plumber's tape wrapped around threaded pipe joints to help create a watertight seal. It's inexpensive and worth using on every threaded connection during a tap installation, since it significantly reduces the chance of a slow leak developing at a joint over the following days or weeks.
: Yes, and it's one of the most common mistakes in a DIY tap installation. Composite and ceramic sinks in particular can crack if the fixing nut underneath is tightened too aggressively. Firm and snug, checked by hand, is enough; you shouldn't need to put your full weight behind a spanner.
: This is normal and expected. There's always some water left in the pipe between the isolation valve and the tap itself, and opening the tap after isolating the supply lets that residual water drain out before you start work. If water keeps flowing steadily rather than trickling out and stopping, your isolation valve may not be fully closed or may be faulty.
: Not usually on a modern deck-mounted tap. PTFE tape seals the threaded connections between the tails and the isolation valves, while the tap base itself normally seals against the sink with a rubber washer supplied in the box. Plumber's putty or a bead of silicone sealant only comes into play if your tap doesn't include that washer, as a substitute for bedding the base watertight.
: Most modern flexible tails use a standard fitting that matches standard UK isolation valves, so this is uncommon on a like-for-like swap. If they genuinely don't match, usually on an imported or unusual tap, you'll need an adapter or a replacement isolation valve in the correct size rather than forcing an ill-fitting joint, which is unlikely to seal properly. Our guide on tap connection sizes covers the fittings you're likely to come across.
: You need one whenever your new tap uses fewer holes than your sink or worktop has, most commonly when switching from a two or three hole set-up to a single hole monobloc tap. Measure your existing holes and check the new tap's specification before buying so you can order a matching blanking plate at the same time, rather than finding out mid-job.