Scheduled visit
Water pressure falls when a second tap runs
A single tap runs fine on its own, but the moment a second tap or a shower opens, both weaken — the flow thins out and the pressure drops until one of them is closed again. It can feel like the whole house has a pressure problem, but the fact that each tap is fine alone points away from the incoming supply and toward a restriction in the shared branch feeding both.
Plumbing
Active leaks are treated as emergencies. Pressure and drainage complaints are normally same-day or next-day.
Call nowRequest a check on WhatsApp01LIKELY CAUSES
What usually sits behind this symptom, and what tells one cause from another.
Partially closed or failing isolating valve
An isolation valve on the branch has been left partly shut, or its washer has swollen or dislodged and is choking the flow.
Restriction in the shared branch or filter
A strainer, filter or flexi hose on the shared run is scaled or blocked, limiting how much water can pass at once.
Undersized or heavily scaled pipe on the branch
The branch is too small for two outlets, or has scaled internally over years, so combined demand exceeds what it can deliver.
A kinked or crushed flexi or supply hose
A flexi hose behind a fixture has been bent or crushed against the wall, narrowing the bore where it connects.
02BEFORE ANYONE VISITS
What you can safely check.
- Confirm each tap is strong on its own and weak only when two run together.
- Check any accessible isolating valves under sinks or behind fixtures are fully open.
- Note which pairs of outlets are affected — kitchen and garden, or both bathrooms — to narrow the shared run.
- Avoid cranking valves open by force; a stiff valve can snap and cause a flood.
03WHAT WE MEASURE
We measure flow at each outlet alone and together, then walk the shared branch back toward the supply, checking every valve, strainer and flexi on the way. Where the restriction is hidden, we test pressure and flow at accessible points to bracket which section is choking before opening anything.
04IN A VILLA
Villa pipework runs further and splits more than in a flat, and every branch, valve and flexi on the way is a place flow can be throttled. A partly-closed isolation valve left behind after a previous repair, or a flexi hose that has scaled internally, will limit combined flow while a single tap still seems fine — which is exactly the signature of this fault.
05THE FIX
Which repair, and when.
Running the house on a choked branch means every simultaneous use — a shower while the washing machine fills, a tap while the garden runs — becomes a contest. The underlying restriction usually worsens, and a valve that is failing can let go entirely.
Open or replace the restricting valve
An isolation valve is partly closed or its washer has swollen.
Clean or replace a blocked strainer or flexi
A filter or flexi on the shared branch is scaled or blocked.
Re-pipe or upsize the shared branch
The branch itself is undersized or scaled beyond cleaning.
06WHAT DECIDES THE FIX
The same symptom can lead to different repairs. These are the things that decide which way it goes.
- Which outlets weaken together — that tells us which shared branch to walk, and how much of it matters.
- Whether the restriction is a valve, a filter or the pipe itself — each has a different fix and a different cost.
- How accessible the branch is — an open valve under a sink is a moment, while a scaled pipe in a wall is a bigger job.
- The age of the pipework — old galvanised or heavily scaled runs may be better replaced than cleaned.
- What flow and pressure measure at each point — the numbers bracket the restriction before anything is opened.
- Whether the pressure was fine until recently — a sudden change usually points at a valve or flexi that has moved or scaled, not the whole branch.
07HOW A VISIT GOES
What to expect when we come out, and why the order matters.
Measure each outlet alone and together
Flow is checked at each outlet on its own and with a second one open, to reproduce the drop.
Walk the shared branch back toward the supply
Every valve, strainer and flexi on the shared run is checked in turn.
Test pressure and flow at accessible points
Where the restriction is hidden, measurements at each point bracket which section is choking.
Open or replace the restricting part
The valve, strainer or flexi that is throttling the flow is put right.
Re-test with two outlets running
The pair of outlets is run together again to confirm the pressure holds.
08KEEPING IT FROM RETURNING
Once it is fixed, these steps make the fault less likely to come back.
- After any repair that touched a valve, confirm it was left fully open.
- Have flexi hoses checked for kinks and scale during plumbing work.
- If a fixture has been replaced recently, check the pressure before and after.
- Note which outlets share a branch so a future drop can be described precisely.
- Have heavily scaled branches descaled or replaced before they choke completely.
- When a valve is worked on, open it fully afterwards and check the flow before the plumber leaves.
09Typical villa plumbing callout
AED 200 – 1,400 depending on access
Tap, trap and fixture work sits low in the band. Pump and vessel replacement sits mid. Anything requiring buried-line access or surface breaking is quoted only after the leak is located, because the location determines most of the cost.
10QUESTIONS
- Is this the pump?
- Usually not, if each tap is strong on its own. The pump serves the whole house, so a pump fault would weaken every outlet, not just when two run together.
- How do I find which taps share a branch?
- Try pairs. If the kitchen and garden weaken together, they likely share a run. If both bathrooms weaken together, that points at the branch feeding them.
- Can I fix it myself?
- Checking that isolating valves are fully open is safe and often revealing. Beyond that, the restriction is usually inside the pipework or a fitting and needs testing to locate.
- Why is the kitchen tap fine on its own?
- Because the restriction limits how much water can pass at once, not whether water flows at all. One tap stays within the limit; two taps together exceed it and both weaken.
- Does low pressure mean I have a leak?
- Not usually. A leak shows up as a bill or a damp patch, while this symptom is a restriction. They are different faults with different signs.
- Will descaling the whole house fix it?
- Only if the restriction is scale in the pipe. If it is a partly-closed valve or a crushed flexi, descaling will not touch it — the restriction has to be found first.