A kitchen renovation succeeds or fails on the plumbing. New cupboards and worktops mean little if the sink waste has the wrong fall, the mixer drips into the carcass, or a dishwasher point was never isolated. In many South African homes — many of which still rely on ageing copper or galvanised pipework — the renovation stage is the ideal time to correct routes, add isolation valves and install the sink, mixer and appliance connections properly.
Plumb A Nator provides professional renovation plumbing in Johannesburg and Cape Town: first-fix pipework, final-fix sink and mixer installation, dishwasher and fridge water points, pressure testing and coordination with your cabinet maker so the finished kitchen performs from day one. We also support related kitchen plumbing repairs and upgrades when a full renovation is not required.
Why plumbing decides the success of a kitchen renovation
Most post-renovation call-outs come from decisions made (or skipped) before the worktops went on. Common problems include:
- Kitchen wastes installed without continuous correct fall — leading to standing water and odours under the sink
- Traps set too high for the new cupboard, so the bowl cannot drain fully
- Missing isolation valves that force a full house shut-off to change a mixer or flexi
- Old galvanised or corroded copper left behind new units and later leaking into carcasses
- Dishwasher wastes tied in above the trap water seal, causing smells or backflow
- Sink relocated without checking the stack or gully position, leaving a flat or back-falling waste
Professional first-fix and final-fix plumbing prevents these outcomes. The work is planned against the new layout, pressure-tested before cupboards close, and coordinated with the cabinet maker so finishes never have to be opened again for a plumbing fault. Where older supply lines are a concern, see our guide on old copper pipes vs modern plastic plumbing.
Kitchen renovation plumbing — stage by stage
A renovation succeeds when the plumbing is planned early, installed correctly and tested before worktops and kick-plates are closed. These are the stages we manage on site in Johannesburg and Cape Town.
Pre-renovation assessment
Before demolition or new pipework begins, we inspect the existing hot and cold supplies, sink waste route, geyser capacity and access for a dishwasher or fridge point. Hidden faults — corroded pipes, inadequate fall, low pressure — are corrected as part of the project rather than discovered once the units are in. If a hidden leak is suspected, our leak detection service can narrow the source before finishes are opened.
First-fix pipework
Hot and cold supplies, the sink waste and any appliance points are installed and pressure-tested while walls and floors are still open. Isolation valves are fitted at the sink and at each appliance. Correct fall is set on every waste run. Only once this stage is signed off should the cabinet maker close the units around the pipework.
Coordination with cabinets and worktops
Sink cut-out size, mixer hole, waste outlet height and dishwasher space are confirmed against the units. Pipes are clipped and protected so they do not rub on carcasses. We leave service access under the sink for traps and valves.
Final-fix fixture installation
The sink, mixer, wastes, plugs and appliance connections are fitted once the worktop is in. Every joint is leak-tested. Both bowls (on a double sink) and the dishwasher tie-in are run so flow and drainage match what the kitchen will see in daily use.
Pressure testing and handover
The complete system is pressure-tested above normal working pressure. Isolation valves are confirmed, mixer operation checked and the work is only signed off once everything meets the required standard. This protects both the homeowner and the builder from expensive post-completion faults.
Get a free quotation from our team
Tell us the scope — sink replacement, full first-fix or a complete kitchen relocation — and we will assess the plumbing, explain the stages and provide a clear quote before any work starts.
Sink, waste and mixer plumbing
The sink is the busiest fixture in the house. The plumbing behind it must be neat, accessible and leak-tested so the cupboard stays dry and the bowls clear quickly.
What we install and check
- Isolation valves on hot and cold so a mixer or flexi change does not require shutting off the whole house
- Correct trap type and waste routing so both bowls on a double sink clear without odour
- 38 mm or 50 mm wastes and matching plugs fitted to the sink specification (including branded Franke-type fittings where supplied)
- Mixer height, reach and hole size matched to the worktop and bowl
- Full leak test under the cupboard before handover
For standalone kitchen leaks outside a full renovation, see our kitchen plumbing service page.
Under-sink wastes, traps and appliance connections
What happens under the cupboard is what keeps the new kitchen dry. Incorrect trap height, a dishwasher waste tied in at the wrong point, or missing isolation are among the most common causes of post-renovation complaints.
Sink waste and trap work
- Continuous fall from each bowl to the wall stub-out or gully
- Correct trap depth so the water seal holds without lifting the waste into the cupboard
- Double-bowl kits connected so one side cannot siphon the other dry
- Leak test of every slip-joint and flange before the kick-plate goes back
Slow or smelling kitchen wastes after a renovation are often corrected under our blocked drain cleaning service — better to set the fall correctly the first time.
Dishwasher and fridge points
- Dedicated isolation on the cold supply for dishwashers and fridge water dispensers
- Dishwasher waste tied in below the sink trap seal at the correct height
- Flexi lengths kept short and supported so they cannot chafe
- Appliance connections tested independently of the sink
Standalone appliance work is also covered on our dishwasher installation and fridge water point pages.
What affects the cost of kitchen renovation plumbing
Plumbing costs form a significant but controllable part of a kitchen renovation. The main factors are:
- Scope of pipework changes — simple sink replacement versus relocating the sink and running new first-fix
- Condition of existing pipes — older copper or galvanised often needs partial or full replacement
- Number of appliance points — dishwasher, fridge water, boiling-water tap or extra prep sink each add a supply and often a waste
- Access and structure — solid walls, under-slab drainage or a sink moved across the room raise labour time
- Geyser work — a second hot run or capacity upgrade adds dedicated pipework and safety valves (see geyser installation)
- Testing and compliance — pressure testing and isolation valves add modest cost but prevent expensive future rework
We always provide a clear, itemised quotation after assessing the site so there are no surprises.
Compliance, CoCs and municipal requirements
Significant alterations to water supply or drainage may require municipal approval depending on the local authority and the nature of the work. Separately, a Plumbing Industry Registration Board (PIRB) Certificate of Compliance (CoC) is required for most plumbing work exceeding R1 500 (including materials, labour and VAT) and for certain categories of work regardless of cost, including sanitary-drain construction or alteration and specified water-heating systems.
Relocating a kitchen sink waste or altering the drain often falls into the CoC category. We advise on the practical requirements for your area and can assist with the necessary documentation so your renovation remains compliant.
Why choose Plumb A Nator for kitchen renovation plumbing
- Free call-out and free quotes — you know the scope and price before work begins
- Stage-by-stage coordination — we work with your cabinet maker so first-fix is complete and tested before units close
- Pressure testing as standard — every new joint is verified before worktops and kick-plates go on
- Isolation valves at the sink and appliances — future maintenance does not require shutting off the whole house
- Local Johannesburg and Cape Town experience — we understand common older pipe materials and the practical constraints of both regions
- 24/7 support — should any issue arise during or after the project, the same team remains available
Frequently asked questions
Can you move the kitchen sink during a renovation?
Yes, in most cases. Drainage fall to the stack or gully, hot and cold routes, cupboard layout and any dishwasher or fridge point must be checked first. We confirm the new position before first-fix so the worktop cut-out and cabinets line up with the plumbing.
Do I need permits or a CoC for kitchen plumbing work?
Municipal approval requirements vary by local authority and the scope of the work. A PIRB Certificate of Compliance is required for most plumbing work above R1 500 and for certain categories such as sanitary-drain alterations. Relocating a sink waste often falls into that category. We can advise on the requirements that apply to your project.
Should I replace old copper or galvanised pipes during the kitchen renovation?
If the existing pipes are corroded, undersized or poorly routed, the renovation is the best time to upgrade. Leaving failing pipework behind new cupboards almost always leads to higher costs later when access is lost. Read more about material choices in old copper pipes vs modern plastic plumbing.
Can you install a sink and mixer I have already purchased?
Yes, provided the products are complete and suitable for the planned connections. We confirm bowl depth versus cupboard height, waste size, mixer hole and whether a dishwasher tail is required before installation, and will flag missing or incompatible fittings early.
How long does kitchen renovation plumbing usually take?
First-fix for a standard kitchen is typically completed in one to two days once the layout is agreed. Final-fix of the sink, mixer, traps and appliance connections follows once the worktops are fitted. Relocating the sink or adding several appliance points takes longer and is scheduled with the cabinet maker.
Do you fit dishwasher and fridge water points in a kitchen renovation?
Yes. Dedicated isolation valves and a correctly trapped dishwasher waste are fitted during first-fix or final-fix. Fridge water points are taken off an isolated cold supply with a suitable flexi and shut-off so the appliance can be serviced without shutting the whole house. See also dishwasher installation and fridge water point installation.
What causes a kitchen sink to drain slowly after a renovation?
The most common causes are insufficient fall on the waste, a trap set too high for the cupboard, an undersized pipe, or a dishwasher waste tied in at the wrong height. We set continuous fall and test both bowls and the appliance connection before handover.
Book a free quotation
Speak directly to our team for practical advice, a free quotation and coordinated first-fix and final-fix plumbing for your kitchen project.