New Home Plumbing.Done Right.

Stages of a new build

Plumbing in a new home comes in stages. Underground drainage goes in before the slab is poured. Rough-in of water pipes, waste and gas happens when the frame is up and before walls are lined. Fit-off of taps, toilets, hot water and appliances comes near the end. Each stage has inspections or sign-offs, so the order matters and cannot easily be swapped.

Questions for your builder

Which hot water system is included, and what are the alternatives? Where are taps, hose cocks and the meter positioned? How many external taps are included? What is the fixture allowance and who chooses the products? How are plumbing variations priced? Get answers in writing before the slab, because moving drains afterwards is expensive.

Choosing a hot water system for a new home

Gas, electric, heat pump and solar systems have different costs and requirements, and Victorian rules on new gas connections have been changing. Ask your builder what is allowed and included, and compare running costs and warranty for each option. See our hot water systems page.

Extras and future-proofing

Consider an external tap on each side of the house, a connection for a future rainwater tank, a laundry or bathroom drain in a space you may convert, and capped points for future gas or outdoor kitchens where they are allowed. Adding these during construction costs far less than adding them later.

After you move in

Run every tap and flush every toilet, check hot water at each outlet, look under sinks for drips and note anything wrong in writing for your builder within the defects period. Learn where the main tap and isolation valves are.

Underground drainage stage

Drainage under the slab is installed before the concrete is poured and needs to be inspected before it is covered. Positions of waste outlets for toilets, showers and floor wastes are fixed at this point, so check them against the plan. A mistake here is hard to correct.

Fit-off stage

At fit-off the plumber installs taps, toilets, basins, the hot water system and appliance connections, then tests the system. Have fixtures delivered on time and tell the plumber about any substitutions. A missing item delays handover.

Plumbing for outdoor living

Outdoor kitchens, showers, pools and irrigation need water, drainage and sometimes gas. Plan them at the start, since adding pipes under finished paving is costly. Check which gas and drainage rules apply to outdoor areas.

Questions people ask about new home plumbing

Who inspects the plumbing?

Plumbing work in Victoria is carried out by licensed plumbers, and some stages involve inspection or compliance certificates. Ask your builder which apply.

Can I choose my own taps and toilets?

Usually yes, within the contract. Check the allowance and supply dates.

Can I add a rainwater tank later?

Yes, but plan overflow, pump position and mains connection early.

What if something leaks after handover?

Report it in writing to your builder within the defects period and keep photos.

Hot and cold supply layout

In a new build the water supply runs from the meter to a manifold or a branch layout, then to each fixture. Long runs to far bathrooms delay hot water and waste water while you wait. Ask your builder where the hot water unit is placed relative to the kitchen, bathrooms and laundry, because a central position shortens the pipes. Insulating hot pipes in the roof space or under the floor saves heat.

Check the pressure at handover as well. A gauge on an external tap shows whether the pressure suits your taps and appliances.

Inspections, certificates and handover paperwork

Plumbing work in Victoria is carried out by licensed plumbers, and some stages involve a compliance certificate or inspection. Ask your builder for copies of the plumbing paperwork at handover, along with the hot water warranty, appliance manuals and a list of the positions of isolation valves and the main tap. Keep them with your house records, since they matter when you sell or claim insurance.

Common defects to look for at handover

New homes are not immune to plumbing faults. Look for taps that drip, toilets that run on, slow drains in showers and basins, hot water that takes a long time to arrive, and hammering noises when a tap is shut quickly. Check under sinks and vanities for damp marks and loose connections. Check that outdoor taps run clear and that downpipes carry water away from the foundations.

Test every tap and flush every toilet. Run the shower and a basin together to see if pressure drops. Write a list with photos and give it to your builder in writing. Defect periods apply to new builds, so ask your builder for the dates and the process for lodging issues.

Maintenance routine for the first two years

A new home has settling to do. Soil moves, timber dries and fittings bed in, which can loosen connections. Check under sinks every few months for damp, test the relief valve on your hot water system as the manufacturer advises, clear gutter and pit debris before storms, and learn where the isolation valves are.

Keep a folder with the plumbing certificate, the product warranties, the model numbers of taps and toilets and your hot water details. When something fails, the folder saves time and makes warranty claims easier. If you add a tap, a filter or an appliance later, have it done by a licensed plumber and add the paperwork.

Guides worth reading

• New Home Plumbing: What Owners Need to Know

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.
• Renovation Plumbing: Plumbing for renovations, extensions and layout changes.
• 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.