Loading...
Plumbing Contract Works · Question
Short answer
Upper floors lose pressure mainly because water has to be pushed or fed from further up the system, and anything undersized, restricted or poorly arranged shows up first at the highest points. Typical causes include an overhead tank too close to the top floor, undersized pipes, pump or valve issues and too many fixtures sharing one riser. A plumbing professional should diagnose which applies.
In a gravity-fed system, pressure depends largely on how far the tank sits above the outlet. The topmost floor sits closest to the tank, so it naturally gets the least head. Lower floors benefit from the extra height. A building with a modest drop between tank and top fixtures will always feel weak at the top, however well the pipework is installed.
Beyond that basic limit, several design and installation causes are commonly examined:
| Cause | General remedy |
|---|---|
| Too little head | Raise the tank, or add a pumped pressure arrangement |
| Undersized pipework | Revise sizing, or reduce load per riser |
| Shared riser | Add separate risers or zoning for upper floors |
| Faulty components | Inspect, correct or replace the affected parts |
Do not alter valves or open lines yourself, and do not accept a pump simply being added without a diagnosis. A qualified plumbing designer or contractor should measure the actual conditions, compare them with the design intent and recommend the fix.
Raise it before handover
Low pressure is easiest to resolve while the contractor is still on site and the contract is open. Note which fixtures are affected and at what times, and ask for the check to be recorded in the handover documents.
Last reviewed
This answer is general information, not advice on your particular case. Terms, eligibility, and requirements change, so check the current position with the relevant institution or authority.