Listen to this article
A kitchen renovation is exciting — new benchtops, cabinetry, appliances. But underneath it all, the plumbing needs to work. Here is what to plan for, from Pete at Water & Gas Worx — PGDB-registered with 17+ years on Auckland tools.
Quick answer: Kitchen plumbing in Auckland costs $300–$600 for a like-for-like sink replacement, $1,500–$3,500 for a sink relocation (including new pipe runs to an island), $200–$500 for a gas cooktop connection on existing gas, $500–$1,500 to run a new gas line to the kitchen, and $2,000–$5,000 for a full kitchen replumb. Water & Gas Worx labour is $155+GST for the first hour and $100+GST per hour after, with all pricing fixed and quoted upfront. Gas Compliance Certificates (GSC) are included with every gas job.
What Plumbing Does a Kitchen Need?
- Hot and cold water supply to the sink (and pot filler if you are fancy)
- Waste drainage from the sink and dishwasher
- Dishwasher connections — water supply and waste
- Gas connection if you have a gas cooktop or oven
- Water filtration if you want filtered drinking water at the sink
- Fridge water line if your fridge has a water dispenser or ice maker
Keeping the Sink in the Same Place
The cheapest and simplest approach is keeping your sink in the same position. The existing water supply and drainage are already there — your plumber just needs to connect the new sink and tapware.
Moving the sink to a different wall or a kitchen island is possible but adds significant cost because new pipe runs and drainage need to be installed.
Gas Cooktop Considerations
Switching from electric to gas cooking (or vice versa) involves more than just swapping the appliance:
- New gas connection: If you do not have gas to your kitchen, a gas line needs to be run from the meter. This requires a qualified gasfitter.
- Gas compliance certificate: Required by law for any new gas connection or modification.
- Ventilation: Gas cooking produces combustion gases. Adequate ventilation (range hood venting outside) is important.
If you already have gas and are replacing a gas cooktop, it is usually straightforward.
Common Kitchen Plumbing Mistakes
Not involving the plumber early enough
Your kitchen designer and plumber need to communicate. The designer needs to know where pipes can go, and the plumber needs to know where fixtures will be. Get your plumber involved before the design is finalised.
Forgetting about the dishwasher
The dishwasher needs its own water supply and waste connection. Its position relative to the sink affects drainage. Make sure your plumber knows where the dishwasher will go.
Ignoring old pipes
If your house has old galvanised pipes, a kitchen renovation is the perfect time for pipe replacement. The walls and floor are already being opened up — doing it later means ripping out your brand new kitchen.
What Does Kitchen Plumbing Cost?
- Sink replacement (same position): $300 to $600
- Sink relocation: $1,500 to $3,500
- Gas cooktop connection (existing gas): $200 to $500
- New gas line to kitchen: $500 to $1,500
- Water filtration system: $500 to $1,200 installed
- Full kitchen replumb: $2,000 to $5,000
Planning a Kitchen Renovation?
Get us involved early and we will make sure the plumbing works seamlessly with your design. Water and Gas Worx handles kitchen renovation plumbing across Auckland. See our pricing or check which areas we service.
Call 0800 322 322 to book a kitchen plumbing job or email service@wgw.co.nz
Frequently Asked Questions
How much does kitchen plumbing cost during a renovation?
It depends on the scope. A straightforward sink replacement in the same position runs $300 to $600. A full kitchen replumb with sink relocation, gas connection, and dishwasher plumbing can range from $2,000 to $5,000. We can quote before starting so you know the cost upfront.
When should I get the plumber involved in my kitchen renovation?
As early as possible — ideally during the design phase before anything is finalised. Your plumber needs to know where fixtures will go, and your designer needs to know where pipes can run. Getting input early avoids costly changes later.
Can I move my kitchen sink to an island bench?
Yes, but it adds significant cost compared to keeping the sink in its current position. New water supply lines and drainage need to be run to the island, and the drainage fall can be tricky depending on the distance. Budget $1,500 to $3,500 for a sink relocation.
Do I need a gas compliance certificate if I install a gas cooktop?
Yes. Any new gas connection or modification requires a gas compliance certificate by law. This is issued by the licensed gasfitter who does the work. It is also important for insurance purposes — never accept gas work without one.