How to install an outdoor tap
Check the steps below first — if you're not confident, get it fixed safely today.
Post a job — we'll find you an engineer →⚠️ Water Regulations require a double check valve or an approved outside tap with built-in backflow prevention to be fitted on all outdoor taps connected to the mains. Failure to fit one is a breach of the Water Supply (Water Fittings) Regulations 1999.
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An outdoor tap must be connected to the mains cold supply (not the hot, and not via a softener if you have one). Locate the rising main — usually the first cold feed after the stopcock under the sink. Plan a route from there through the wall to the outside tap position.
Turn off the mains water at the internal stopcock. Drain the pipe by opening a tap downstairs. Mark the drill position on the outside wall for the tap backplate — ideally below a kitchen window for easy pipe routing.
Drill through the wall using a long masonry bit (22mm or a proprietary core bit for outside tap kits). Angle slightly downward from inside to outside so water drains away from the wall naturally.
Fit the outside tap backplate onto the wall (plugs and screws supplied in the kit). Thread the wall pipe through the hole. Inside, install a 15mm tee into the rising main using compression fittings or push-fit. Run a branch pipe to the wall penetration.
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Frequently asked questions
Do I need planning permission to install an outdoor tap?
No — fitting an outdoor tap does not require planning permission. However, Water Regulations require a double check valve to be fitted to prevent backflow contaminating the mains supply. This is a legal requirement, not optional.
Where is the best location for an outdoor tap?
Ideally close to the kitchen or utility room where the rising main is accessible, minimising pipe run length. Position it where you can reach the hose from the main use areas of the garden, and where the pipe can be routed without going through habitable rooms or structural walls. A south-facing wall stays frost-free longer in winter.
How do I winterise an outdoor tap?
In October, close the indoor isolation valve for the outdoor tap and open the outside tap fully to drain any residual water from the exposed section. Leave the outside tap slightly open over winter so expansion can't build up. In spring, close the outside tap and reopen the indoor isolation valve.