Renovation Plumbing.Done Right.

Plumbing in a renovation

A renovation touches the plumbing whenever a bathroom, kitchen or laundry is moved, enlarged or updated. Even a cosmetic update can reveal old pipes, tired valves or drains that do not suit new fixtures. Planning plumbing at the start saves cutting into finished walls and floors later.

Plan the plumbing before the layout is fixed

Moving a toilet, shower or sink changes the pipes behind it. A layout that suits the existing drainage is cheaper than one that fights it. Ask a plumber to look at plans before cabinets are ordered or walls are framed, since a small shift of a fixture can avoid cutting a slab or running a long drain.

Stages of plumbing in a renovation

Most renovations need a rough-in stage, when pipes are placed before walls are closed, and a fit-off stage, when taps, toilets and appliances are connected. Other trades finish walls and floors between the two. Missing the rough-in window means opening walls later, so build the dates into your schedule with your builder.

Old homes and what is behind the walls

In older houses, plumbing can include galvanised pipe, cast iron drains and layers of earlier repairs. Opening a wall can reveal pipes that need replacing. Agree beforehand how decisions about extra work will be made, so the project does not stall while you wait for answers.

Extensions and new drainage

An extension that adds a bathroom or kitchen usually needs new drainage connected to the existing sewer. The line needs a suitable fall and a connection at the right point. A camera inspection before the design is settled shows whether the existing sewer can take the extra load.

Services you may need to upgrade

An old house may have low pressure, a small hot water system or a main supply pipe that cannot feed a larger bathroom. A renovation is a good time to check these while walls are open. Ask what condition the existing pipes are in and whether the water and gas supply suit the new layout.

What changes the price and the schedule

A plumbing quote for a renovation depends on how many fixtures move, how hard the access is, what is already in the walls and which fixtures you choose. Ask for a list of what is included and what is not, such as tapware supplied by you, drainage changes or work behind finished walls. Variations are normal, but a clear starting list reduces surprises.

Fixtures, lead times and compliance

Taps, basins and toilets can take weeks to arrive, and a missing fixture holds up fit-off. Order early and give your plumber the model numbers so rough-in dimensions can be checked. Plumbing work is done by licensed plumbers, and some work needs a compliance certificate, so ask what applies and keep the paperwork with your building records.

Questions people ask about renovation plumbing

Should the plumber visit before demolition?

Yes. They can tell you where services run, what is likely to be behind the walls and what the layout will need.

Can I supply my own fixtures?

Often yes, but check dimensions, rough-in positions and warranty conditions first. Installation of customer-supplied products may carry limits on warranty.

How long are the taps and toilet out of use?

It depends on the job. Ask for the planned shut-off periods so you can arrange alternatives.

Does the plumber coordinate with the builder?

We work with builders and other trades. Tell us who the main contact is and the dates for each stage.

A walk-through before the work starts

Ask the plumber to walk the house before demolition. Locate the main tap, meter, hot water system, gas meter and the line of the main drain. Mark where each fixture is going on the plan, and ask what is needed for each: hot and cold supply, waste, vent, gas, power or a floor waste. This conversation avoids discovering at rough-in that a drain cannot reach the position you wanted.

If you are using a builder, include the plumber in the planning, not just at rough-in.

Typical sequence on a bathroom or kitchen

Demolition comes first, then rough-in of pipes and drains, then wall lining, waterproofing and tiling, then fit-off of taps, toilet, basin and appliances. Plumbing appears twice, before and after other trades. Delays in tiling or cabinetry push fit-off back, so tell your plumber early when dates move.

Questions to put in a plumbing quote

Which fixtures are included and who supplies them? Is rough-in and fit-off in one price? What is the allowance if the existing drain needs work? How will hidden problems be handled and priced? Which paperwork will be provided at the end? A quote that answers these before work starts reduces arguments later.

Staging plumbing with other trades

Plumbing comes in stages, rough-in before walls are lined, waterproofing before tiling, and fit-off at the end. Share the schedule with your builder and tiler so a plumber is booked for the right stage.

Changes after the walls close are slower and cost more. Settle fixture positions early.

Hot water and drainage capacity in a renovation

Adding a bathroom or a larger kitchen can exceed the capacity of the hot water unit or the drain. Ask the plumber whether the existing system suits the new layout, and whether pipe sizes and fall are enough.

It is easier to upgrade the hot water or the drain while walls are open.

What to give your plumber before the quote

Plans, a list of fixtures with model numbers, photos of the existing plumbing, the position of the hot water unit and meter, and your budget range help the plumber quote accurately. If you are using a builder, share the builder's scope too. Say whether you are keeping any existing fixtures.

A clear scope reduces variations. Ask the plumber what is included, such as removal of old fixtures, patching, testing and certificate paperwork, and what would count as an extra.

Guides worth reading

• Renovation Plumbing: What to Plan Before You Start
• Plumbing Problems in Older Homes: What to Look For Before They Cost You

Related plumbing services

• Bathroom Renovation Plumbing: Rough-in and fit-off plumbing for bathroom renovations and new bathrooms.
• Kitchen and Laundry Plumbing: Plumbing for new and renovated kitchens and laundries.
• New Home Plumbing: Plumbing for new homes from slab stage to final fit-off.
• Emergency plumbing is available 24 hours a day, 7 days a week

Talk to GSA Plumbing Services

Call 0401 041 103 or send an enquiry on the contact page. We work across Geelong, Melbourne and surrounding suburbs.