Plumbing, building & developing involves planning water supply, drainage, wastewater, stormwater and plumbing services alongside the wider construction or development process. In Australia, plumbing work must be planned around applicable building requirements, plumbing standards, approvals and state or territory licensing rules.
For a new home, renovation, commercial premises, shop fit-out or development, getting the plumbing strategy right early can prevent costly changes later.
The National Construction Code (NCC) includes Volume Three, the Plumbing Code of Australia (PCA), which covers areas including water services, sanitary plumbing and drainage, stormwater drainage and certain wastewater systems.
Plumbing is not simply about installing pipes after the building is designed. Pipe routes, drainage falls, fixtures, access points, water pressure and connection requirements can influence the building layout itself.
What Should You Plan Before Starting a Building or Development Project?
The first step is to understand the site’s existing services, proposed building layout and plumbing requirements before construction begins.
1. Identify existing water and drainage services
Before excavation or demolition, establish:
- Where existing water services enter the property
- Where sewer and drainage lines are located
- Whether stormwater infrastructure is available
- Where water meters are positioned
- Whether easements or authority assets affect the site
- Whether existing plumbing can support the proposed development
Never assume that an old drainage plan accurately represents what is underground.
2. Match the plumbing design to the building
A residential renovation may require a completely different plumbing approach from a restaurant, retail shop, warehouse or multi-unit development.
Consider:
- Number of bathrooms and fixtures
- Kitchens and commercial sinks
- Hot-water requirements
- Toilets and sanitary drainage
- Stormwater
- Trade waste where applicable
- Backflow prevention
- Water pressure
- Pumping requirements
- Future maintenance access
Expert insight: A cheap plumbing layout that is difficult to access can become expensive when a blocked drain, leaking pipe or failed valve needs repair years later.
What Plumbing Requirements Apply to Building and Development Projects in Australia?
Australian plumbing requirements are governed by national and state or territory rules, so the exact requirements depend on the location and type of work.
The NCC provides national construction requirements, while individual jurisdictions administer licensing, approvals and other regulatory processes. The Australian Government’s business licensing service states that NCC Volume Three applies to the design, construction, installation, replacement, repair, alteration and maintenance of plumbing and drainage installations.
The main areas to check
| Area | What may need consideration |
|---|---|
| Water supply | Pipe sizing, pressure and connection |
| Sanitary plumbing | Toilets, basins, showers and fixtures |
| Drainage | Waste pipes, sewer connections and falls |
| Stormwater | Roof drainage and site discharge |
| Backflow | Protection of potable water supplies |
| Hot water | System selection, installation and safety |
| Products | Applicable certification and suitability |
| Approvals | Authority, council or plumbing requirements |
| Compliance | Inspection and required documentation |
Requirements can differ between Victoria, NSW, Queensland, South Australia, Western Australia and other jurisdictions. A plumber or builder should confirm the applicable rules for the specific site rather than relying on a generic national checklist.
Do You Need a Licensed Plumber for Building and Development Work?
Yes, many types of plumbing work must be performed by appropriately licensed or registered plumbing professionals, with requirements varying between Australian jurisdictions.
For example, Victoria’s licensing framework includes different classes and subclasses of plumbing work. A licensed plumber can undertake the plumbing work covered by their licence, design relevant work, supervise apprentices and other plumbers within the applicable scope, and issue compliance certificates where authorised.
Why licensing matters
A qualified plumbing professional can help with:
- Plumbing design and installation
- Drainage systems
- Water services
- Renovation plumbing
- Commercial plumbing
- Hot-water systems
- Stormwater work
- Fault finding
- Testing and compliance
- Required documentation
Expert insight: Always check that the plumber’s licence covers the type of work being undertaken. Specialist work can have additional requirements.
What Is the Plumbing Code of Australia?
The Plumbing Code of Australia is Volume Three of the National Construction Code and provides technical provisions for plumbing and drainage systems.
It addresses areas such as:
- Water services
- Sanitary plumbing and drainage
- Stormwater drainage
- Certain heating, ventilation and air-conditioning systems
- On-site wastewater management
- Trade waste and related systems
The Australian Government’s business licensing information specifically identifies NCC Volume Three as the Plumbing Code of Australia and states that it applies to licensed plumbers undertaking relevant design, installation, repair, alteration and maintenance work.
What does that mean for property owners?
You do not need to become a plumbing-code expert before renovating or developing.
Instead, your project team should identify:
- Which plumbing rules apply
- Which approvals are necessary
- Which products can be installed
- Who is responsible for certification
- What inspections are required
- What documentation must be retained
Consider compliance during planning, not as paperwork to deal with after the work is finished.
Are Plumbing Products Required to Be WaterMark Certified?
Some plumbing and drainage products are subject to WaterMark certification requirements, so product suitability should be checked before installation.
The WaterMark Certification Scheme is used for applicable plumbing and drainage products, and the NCC contains requirements concerning product certification and authorisation.
What should builders and businesses check?
Before purchasing plumbing products, consider:
- Whether the product falls within a WaterMark category
- Whether it is certified and authorised where required
- Whether it is suitable for its intended application
- Whether manufacturer installation instructions apply
- Whether evidence of suitability needs to be retained
This is particularly relevant when selecting unfamiliar imported products or unusual plumbing components.
Don’t choose plumbing products solely because they are cheaper. A product that is unsuitable or cannot demonstrate required compliance can create installation, approval and maintenance problems.
What Plumbing Work Is Needed During a New Build?
A new building typically requires plumbing to be coordinated from the earliest design stages through installation and final commissioning.
Typical plumbing stages
1. Planning
Review architectural drawings, site information and service locations.
2. Plumbing design
Determine pipe routes, fixture locations, drainage requirements, water supply and other services.
3. Underground services
Install or prepare underground drainage, sewer, water and stormwater infrastructure as required.
4. Rough-in plumbing
Install concealed pipes before walls, floors and ceilings are completed.
5. Fixture installation
Connect toilets, basins, showers, sinks, taps, appliances and other plumbing fixtures.
6. Testing and inspection
Test the installation and complete required inspections or certification.
7. Final commissioning
Confirm that the system operates correctly and that required documentation has been completed.
Plumbing mistakes become harder and more expensive to correct once walls, floors, cabinetry and landscaping are finished.
How Does Plumbing Affect Renovations and Commercial Development?
Plumbing affects renovations and commercial development because changing the location or number of fixtures can require new water, drainage, stormwater or specialist plumbing infrastructure.
Bathroom renovations
Moving a toilet, shower or basin can involve more than extending a water pipe. Drainage gradients, pipe locations, floor construction and access all need consideration.
Kitchen renovations
A new kitchen may require:
- Sink waste connections
- Dishwasher plumbing
- Water supply
- Isolation valves
- Wastewater capacity
- Appliance connections
- Changes to existing pipework
Shops and commercial premises
Commercial properties may require more detailed planning because plumbing demand can be higher and the business may use specialist equipment.
Depending on the business, consider:
- Multiple bathrooms
- Staff amenities
- Commercial kitchens
- Trade waste
- Grease arrestors
- Backflow prevention
- High-demand hot water
- Floor wastes
- Drainage capacity
For businesses, plumbing should be designed around how the premises will actually operate—not simply around the fixtures shown on an architectural drawing.
What Should Developers Check Before Connecting a New Development?
Developers should confirm water, sewer, stormwater and authority requirements before construction because development can require new connections, service upgrades or infrastructure works.
Requirements vary by location and water authority. For example, Sydney Water identifies building plan approvals, connections, meters, backflow prevention and development-related servicing requirements as separate considerations.
A practical development checklist
Before starting work:
- Confirm existing services.
- Check property boundaries and easements.
- Review engineering and architectural plans.
- Determine water and sewer connection requirements.
- Check whether authority approval is required.
- Confirm stormwater arrangements.
- Identify backflow requirements.
- Confirm plumbing licensing requirements.
- Select compliant plumbing products.
- Plan inspections and certification.
Development approvals and infrastructure requirements can affect construction timing, site layout and project costs.
How Can Businesses Reduce Plumbing Problems During Construction?
Businesses can reduce plumbing problems by coordinating the plumber, builder, designer and other trades before construction starts.
Use a coordinated site plan
Your plumbing contractor should understand where other services will run, including:
- Electrical
- HVAC
- Gas
- Structural elements
- Waterproofing
- Fire services
- Stormwater
- Landscaping
Protect future maintenance access
Valves, pumps, inspection openings and other serviceable components should remain accessible where required.
Document changes
If the installed plumbing differs from the original design, update the relevant documentation rather than relying on memory.
Good plumbing design is not just about making water flow. It should make the building easier to operate, maintain and repair.
What Are the Most Common Plumbing Mistakes in Building Projects?
The most common problems often begin during planning rather than at the final installation stage.
Mistake 1: Starting without checking existing services
Unknown pipes and drains can cause delays, damage and redesign work.
Mistake 2: Moving fixtures without checking drainage
A new fixture location may not work simply because a water pipe can reach it.
Mistake 3: Choosing products based only on price
Cheap or unsuitable products can create compliance and reliability issues.
Mistake 4: Ignoring future maintenance
A pipe or valve hidden behind inaccessible construction can make future repairs unnecessarily difficult.
Mistake 5: Leaving plumbing until the end
Late plumbing decisions can conflict with structural, electrical, cabinetry and architectural requirements.
Mistake 6: Assuming every Australian project follows identical rules
Licensing and approval processes are administered by individual jurisdictions, so requirements must be checked locally.
How Can Pro Tap Plumbing and Maintenance Help?
Pro Tap Plumbing and Maintenance can assist with professional plumbing services for property owners, businesses and building or renovation projects across Australia, subject to service availability and the applicable local requirements.
Depending on the project, professional plumbing support can include:
- Plumbing repairs
- Plumbing maintenance
- Drainage services
- Burst and leaking pipe repairs
- Renovation plumbing
- Commercial plumbing
- Emergency plumbing
- Water-related plumbing problems
- General plumbing installation and servicing
For a building, renovation or development project, involve your plumber early enough to review the proposed work rather than waiting until construction is underway.
Early plumbing input can identify practical issues before they become expensive construction changes.
Frequently Asked Questions About Plumbing, Building & Developing
What does plumbing, building and developing involve?
Plumbing, building and developing involves coordinating water supply, drainage, wastewater, stormwater and plumbing infrastructure with construction or property-development plans. The exact approvals and standards depend on the location and project.
Do I need a licensed plumber for a renovation in Australia?
Many plumbing jobs require an appropriately licensed or registered plumber, but requirements vary by state or territory and by the type of work. In Victoria, for example, plumbing work is regulated through specific registration and licensing classes.
What is the Plumbing Code of Australia?
The Plumbing Code of Australia is NCC Volume Three and contains technical requirements covering plumbing and drainage installations. It forms part of Australia’s National Construction Code framework.
What is WaterMark certification?
WaterMark is Australia’s certification scheme for applicable plumbing and drainage products. Where certification is required, the product must meet the relevant requirements before it can be used in the applicable plumbing installation.
Should plumbing be planned before building starts?
Yes. Plumbing should be coordinated during the design and planning stage because drainage routes, fixture locations, pipework and service connections can affect building layouts and construction sequencing.
Can a plumber help with a commercial building project?
Yes. A suitably licensed commercial plumber can help with plumbing installation, maintenance, drainage and other plumbing requirements within their licence scope. Larger projects may also require coordination with builders, hydraulic designers, engineers and relevant authorities.
Successful plumbing, building & developing starts with planning the plumbing infrastructure alongside the building itself. Checking local requirements, engaging appropriately licensed professionals and selecting suitable products can help reduce construction problems and future maintenance issues.
If you are planning a renovation, commercial project, new build or urgent plumbing repair, contact Pro Tap Plumbing and Maintenance to discuss the plumbing work your property requires.