How to Install a Garden Tap (Without Cracking Brick or Render)

Hassan Ibrahim
3 days ago
5 min read

Drilling a hole for a 15mm pipe sounds simple.

Until:

The tap plate won’t fit properly
The plugs have nothing to grip
The pipe is jammed tight in the wall
Or the brick blows out on the outside face

👉 The hole size matters more than people think.

And for garden taps especially—

There’s a much cleaner way to do it.

The Best Method for a 15mm Garden Tap Pipe

A lot of people drill one oversized hole and hope for the best.

Bad idea.

The better method is:

👉 Start small for positioning👉 Then enlarge the hole once the fixings are marked

This gives you:

Better fixing support
Cleaner alignment
Proper pipe protection
A more professional finish

Step 1 — Drill a 16mm Hole First

Start with:👉 A 16mm masonry drill bit

This is your positioning hole.

Not your finished hole size.

The reason for this is simple:

The fixing screws for garden taps sit very close to the pipe entry point.

If you drill a massive hole first—

You weaken the area where your screws and rawl plugs need to grip.

Step 2 — Position the Tap Plate

Now hold your tap back plate in place and mark the fixing holes.

Once marked:

👉 Drill those fixing holes with a:

6mm masonry drill bit

Then install:

Red rawl plugs

Now your fixing points are set properly before enlarging the centre hole.

This is the important bit most people miss.

Step 3 — Open the Main Hole to 22mm

Now enlarge the centre hole using:👉 A 22mm masonry drill bit

This gives enough room to fit:👉 A 20mm PVC conduit sleeve

And honestly—

This is the proper way to do it.

Why Use a Sleeve?

The sleeve protects the copper pipe from the masonry.

That helps:

Prevent rubbing
Reduce wear over time
Allow slight expansion and movement
Give a cleaner finish

Cut the conduit flush to the wall thickness and leave it inside the hole.

Simple.

But much better long term.

Final Assembly

Now:

Pass your 15mm copper pipe through the sleeve
Apply silicone behind the tap plate
Screw the plate firmly to the wall

👉 The silicone helps stop water getting behind the fitting.

And because your fixing holes were drilled before enlarging the centre hole—

The screws still have strong masonry around them to grip into.

What About Normal Indoor 15mm Pipes?

For standard indoor pipe runs through masonry—

👉 18mm–20mm holes are usually ideal.

Because you want:

Easier installation
Slight movement allowance
Room for expansion and contraction

Especially on hot pipes.

A tightly wedged pipe can:

Creak
Expand noisily
Rub against masonry over time

A little clearance helps.

Don’t Forget Pipe Protection

If the pipe is passing through masonry—

👉 Protect it if possible.

Sharp brick edges can wear against copper over time.

A conduit sleeve is ideal, but you can also use:

Self-amalgamating plumber’s tape
Pipe wrap
Protective sleeving

Small detail.

Big difference long term.

Drill Technique Still Matters

Even with the correct hole size:

Drill straight
Don’t wiggle the drill
Clear dust regularly
Let the drill do the work

👉 Widening the hole accidentally defeats the whole point of sizing it correctly.

Pro Tip: Avoid Brick and Render Blowouts

This catches people out constantly.

You drill through the wall—

And the outside brick face or render explodes out at the end.

👉 That’s usually caused by the hammer action during breakthrough.

If possible:👉 Drill from the outside in.

If you must drill from inside out:

Drill a small pilot hole first
Mark your wall depth on the bit with tape
Stop hammer mode just before breakthrough
Switch to drill-only mode for the final section

That small change makes a huge difference.

Especially on:

Render
Face brickwork
Old masonry

Connecting to a Cold Water Feed

A garden tap should always be connected to a:👉 mains cold water pipe

Usually this is taken from:

Under the kitchen sink
Utility room pipework
Garage cold feed

Turn the Water Off First

Before cutting anything:

👉 Turn the mains water off.

Then open the kitchen tap to drain pressure from the pipework.

Tee Into the Cold Pipe

Most installs use:

A 15mm tee fitting

Cut into the cold pipe and branch off towards the outside wall.

Depending on your pipework, this can be:

Copper
Speedfit / push-fit
Compression fittings

Fit an Isolation Valve

Very important.

👉 Install an isolation valve on the garden tap feed.

This allows you to:

Shut the outside tap off in winter
Carry out repairs later
Isolate problems quickly

Ball valves are ideal.

Don’t Forget a Double Check Valve

This is important for backflow protection.

A garden tap should have:👉 A double check valve

Some taps have one built in.

Some don’t.

Check before installing.

This helps stop contaminated water flowing back into the mains supply.

Run the Pipe to the Wall

Now run your 15mm pipe towards the wall hole.

Keep clips neat and secure.

Avoid:

pipe strain
unsupported pipework
sharp bends

Test Everything Before Finishing

Before boxing anything in:

👉 Turn the water back on and test:

joints
tap fittings
wall entry point

Check carefully for leaks.

Even tiny drips matter.

🔚 Final Thought

Installing a garden tap properly isn’t just about getting water outside.

It’s about:

Drilling the wall cleanly
Protecting the pipe
Keeping the fixings strong
Preventing leaks and movement later

The small details matter.

👉 Accurate drilling, proper sleeving, good support and correct pipe routing are what make the difference between:

A garden tap that lasts years…

And one that ends up loose, leaking or cracking the wall around it.

Take your time.

Do it once.

Do it properly.

❓FAQ: How to Install a Garden Tap

What size hole do I need for a 15mm garden tap pipe?

A good method is:

16mm first positioning hole
Then widen to 22mm for a 20mm protective sleeve

This gives better fixing support and pipe protection.

What size drill bit for a garden tap pipe through brick?

Usually:

16mm for the initial hole
22mm for the final sleeved hole

Should I sleeve copper pipe through a wall?

Yes.

A sleeve helps:

Protect the pipe from masonry
Prevent rubbing
Allow slight movement and expansion

20mm conduit pipe works well for 15mm copper pipe.

How do you stop brick or render blowout when drilling?

Switch the drill from hammer mode to drill-only mode before the final breakthrough.

Drilling from outside in also helps reduce visible damage.

Can I install a garden tap from the kitchen cold pipe?

Yes — that’s one of the most common methods.

Usually from:

Under the kitchen sink
Utility room cold feed
Garage cold supply

Do I need an isolation valve for a garden tap?