What the job involves
Fitting a new outside tap means taking a drinking-quality water supply from inside the house to a tap on an external wall. For a standard job, the plumber finds a suitable mains-fed pipe, usually under the kitchen sink or in a utility room or garage. They fit a branch off it, run a short length of pipe to the outside wall, and drill through the wall. The tap goes on the outside face, and an isolation valve is fitted on the inside.
The isolation valve matters. It lets you shut the supply to the tap in autumn, and a small drain-off point lets you empty the pipe before frost. A burst pipe behind a wall is a far bigger problem than the tap itself.
Outside taps also need backflow protection. UK water fittings rules require it so that garden water, such as from a hose left in a pond or a bucket of fertiliser, cannot be drawn back into the house supply. Many modern outside taps have a double check valve built in. Otherwise the plumber fits one separately. A competent plumber will do this without being asked, but check it is included.
This page covers the typical scope of one tap with an isolation valve. Extras such as a second tap, a long run to a detached building or an outside socket are different jobs and are priced differently.
What affects the price
- Distance from the existing supply. A tap on the wall directly behind the kitchen sink is quick. A tap at the far side of the house, with pipe running through rooms or under floors, takes more pipe, more fittings and more labour.
- Wall construction. Drilling through a single brick wall is straightforward. Thick stone, solid walls or a cavity wall with insulation take longer and need more care. A core drill is sometimes needed, and the hole must be sealed properly.
- Access to the pipework. Pipes in an open cupboard are easy to reach. If the supply is boxed in, under a fitted floor or behind units, the plumber has to spend time getting to it and making good afterwards.
- Type and quality of tap and valves. A basic bib tap with a separate check valve costs less than a frost-resistant or lockable tap with built-in backflow protection. Brass and better-finished fittings last longer outdoors.
- Pipework route and materials. Copper looks neater when surface-run, while plastic push-fit or barrier pipe can be quicker to install. The choice depends on the route and on what is already in the house.
- Whether the supply is suitable. The tap should come off a mains-fed pipe. If the property has an unusual layout or the pipework is old or in poor condition, extra work may be needed.
- Making good. Filling holes, sealing round the pipe and tidying internal boxing or decoration can add time, especially on rendered or painted walls.
- Your location and the plumber's availability. Labour rates vary across the UK, and small jobs can cost more per hour where plumbers are busy. Parking or travel time may also be reflected.
- Combining jobs. A tap fitted during other plumbing work is often cheaper than a separate visit, because the call-out and set-up time is shared.
Ways to keep the cost down
- Choose the tap position sensibly. The nearest suitable external wall to a mains-fed pipe keeps pipe runs short. Be realistic about where you will use it most, though. A tap you cannot reach with a hose is a poor saving.
- Clear the way before the plumber arrives. Empty the cupboard under the sink and move items away from the outside wall. Time spent moving things is time you pay for.
- Bundle small jobs. If you also need a dripping tap fixed, a washing machine valve replaced or a new isolation valve fitted elsewhere, ask for it all in one visit.
- Get several quotes for the same scope. Describe the job the same way each time and say where the tap will go. Photographs of the sink area and the outside wall help plumbers quote accurately without guessing.
- Do not buy cheap fittings to save money. An outside tap is exposed to weather and frost, so a better-quality tap usually lasts longer.
- Ask what the plumber can supply. Some plumbers have trade accounts and can source fittings at a good price. Others are happy to fit a tap you have bought, though they may not guarantee the part.
- Do the making good yourself. If you are happy to repaint or fill small marks, say so. Do not skip sealing round the pipe, though.
What should be included in a quote
- [ ] The tap itself, including its type, such as bib tap, anti-frost or lockable
- [ ] An isolation valve with a drain-off point, fitted inside
- [ ] Backflow protection, such as a double check valve, either built in or separate
- [ ] Where the supply will be taken from and the approximate pipe route
- [ ] Drilling through the wall and sealing the hole weatherproof
- [ ] Pipework and fittings
- [ ] Making good inside and outside, or a clear note of what is not included
- [ ] Labour and any call-out or minimum charge
- [ ] VAT, if the plumber is VAT-registered
- [ ] Disposal of waste and protection of floors and worktops
- [ ] Guarantee or workmanship warranty
- [ ] Anything that might change the price, such as discovering an unsuitable supply pipe
Questions to ask a plumber
- Will the tap be fed from the mains, and where exactly will you connect to it?
- Does the tap have backflow protection, or are you fitting a separate valve?
- How will I drain the pipe for winter, and can you show me where the valve is?
- What will you do about the hole through the wall, and how will it be sealed against damp and draughts?
- Is the quote fixed, or could it change once you see the pipework?
- Is making good included, or do I need to arrange decorating myself?
- Do you guarantee the work, and what is covered?
- Will you isolate the water, and how long will the supply be off?
- Do you carry insurance for work in my home?
How long it takes and what to expect
A straightforward installation is usually a short job, often a half day or less. The plumber will isolate the water, drain the relevant pipe, make the connection and drill through the wall. Then they fit the tap and the valves, restore the water and check for leaks. Expect some noise, a little dust, and the water off for a short time. Keep the area under the sink and round the outside wall clear.
If the pipe run is long, the wall is thick or the access is difficult, the job takes longer. Tell the plumber about any cables, pipes or damp problems you know of in the wall. They should also check for hidden services before drilling.
When the job is done, run the tap, check the isolation valve works and look for drips at the joints. Ask to be shown how to turn the supply off and drain the tap for winter. Keep any guarantee paperwork.
Signs a quote is too cheap or too expensive
Possibly too cheap
- No mention of backflow protection or an isolation valve
- Vague wording such as "fit outside tap" with no detail on materials, route or making good
- A plumber who will not say where the supply comes from
- No guarantee, no insurance or no willingness to put the quote in writing
- A price far below the others for the same scope, often meaning corners will be cut or extras added later
Possibly too expensive
- A long list of extras for a job that is simple on paper
- A large call-out or minimum charge with no explanation
- Premium fittings you did not ask for
- No breakdown, so you cannot tell what you are paying for
- A quote that assumes difficult access or long pipework when the tap is next to the supply
Compare your quote with the prices on this page, then ask the plumber to explain any big differences. A good plumber should be happy to explain the price in plain terms.