New Build Plumbing Guide for South West Homes

A new home can look finished long before the plumbing has proved itself. Pipes are hidden behind walls, drainage is buried under slabs and lawns, and decisions made at the plan stage can affect water pressure, running costs and maintenance access for decades. This new build plumbing guide helps South West homeowners, builders and owner-builders ask the right questions before work begins.

Start Plumbing Planning With the Floor Plan

Plumbing works best when wet areas are planned with purpose. Bathrooms, laundries, kitchens and outdoor taps all need water supply, drainage and ventilation. Grouping wet areas near each other can reduce pipe runs and installation costs, but it should not come at the expense of a practical layout.

Think about how the home will be used, not only how it will look on the plans. A second bathroom may be used heavily when family visit. A mudroom laundry may need a deeper trough and more floor drainage. A kitchen island could require water for a sink, dishwasher and filtered-water tap. Small choices at this stage are much easier to accommodate before the slab is poured.

Also allow enough room for access. Isolation valves, hot water units, water filters, pumps and drainage inspection points should be reachable without removing cabinetry, digging up garden beds or working around stored items. Easy access makes future servicing quicker and less disruptive.

Confirm Fixture Locations Before the Slab

Once under-slab drainage is installed, moving a toilet, shower or kitchen sink position can become expensive. Before approving the plumbing set-out, confirm the final locations of toilets, basins, baths, showers, floor wastes, laundry appliances and the kitchen sink.

This is also the right time to check door swings, vanity sizes and shower screen layouts. A toilet pan may technically fit on a plan but still feel cramped once walls, tiles and cabinetry are in place. Your plumber should work closely with the builder and other trades so pipework is positioned accurately from the outset.

Water Supply: Pressure, Pipework and Outdoor Use

Your water supply needs to suit both the home and the block. In Busselton and across the South West, that can mean considering town water, rainwater tanks, bore water, rural supplies or a combination of sources. Each arrangement has different requirements for pumps, filtration, backflow prevention and connections.

Ask early how many external taps you need and where they should be located. It is sensible to provide taps near the front garden, backyard entertaining area, shed, clothesline and any future veggie patch. A tap at the right location is far more useful than relying on long hoses across paths and lawns.

Water pressure should also be considered before selecting tapware. Some fixtures perform poorly if pressure is low, while high pressure may need control to protect plumbing components. If a rainwater tank will supply toilets, laundry cold water or garden taps, the pump capacity and changeover arrangement should be designed for the intended demand.

For coastal or rural properties, water quality can influence fixture choice and maintenance. Filtration may be worthwhile where sediment, mineral content or tank water affects taste, appliances or fittings. The right solution depends on the water source and should be assessed as part of the overall plumbing plan.

Drainage and Stormwater Need Separate Attention

Household wastewater and stormwater are different systems. Wastewater drainage carries water from toilets, basins, showers, sinks and laundry fixtures. Stormwater manages rain falling on the roof and hard surfaces. Both must be installed correctly, but they face different demands.

A drainage plan should account for the building footprint, fall of the block, connection points and future landscaping. The aim is to move wastewater reliably to the approved point of disposal while allowing the system to be inspected and maintained if needed.

Stormwater deserves particular care on South West blocks where heavy rain, sandy soils, low-lying areas or changing ground levels can affect how water moves. Roof catchments, downpipes, soakwells, surface drainage and overflow paths need to work together. Water should not be directed towards the house, neighbouring property or areas likely to become difficult to access.

Do not leave stormwater decisions until landscaping begins. Retaining walls, paving, pools, driveways and garden beds can all change drainage behaviour. Planning ahead helps avoid puddling near doors, erosion around paths and costly alterations once the property is finished.

Include Inspection and Maintenance Points

Good drainage is not just about what happens on installation day. Inspection openings and sensible access points allow a plumber to investigate a blockage or carry out a camera inspection later without unnecessary excavation. This matters on any property, but especially once concrete, paving and established gardens are in place.

Avoid planting large trees directly over drainage lines where possible. Roots can seek moisture through small joints or damaged pipework, creating blockages that are difficult to clear. Your final site plan should show where key services run so future work does not accidentally damage them.

Choose Hot Water for Your Household, Not the Display Home

Hot water is one of the most noticeable parts of daily living. The right system depends on household size, bathroom numbers, expected shower use, available energy sources and installation location.

A storage system can be a practical choice for some homes, particularly where several people use hot water around similar times. Continuous-flow gas units provide hot water as required and can save space, although their performance depends on correct sizing and gas supply. Heat pump systems can offer lower running costs in suitable situations, but need the right location, electrical provision and consideration of operating noise.

There is no single best option for every build. A couple in a compact home may have very different needs from a family with teenagers, a large bath and two showers running before school. Discuss anticipated use honestly before choosing capacity.

The unit location matters as well. Consider distance to bathrooms and the kitchen, service access, drainage for relief valves, safe clearances and whether the area will remain practical once fencing and landscaping are completed. Long pipe runs can mean more waiting and water wastage before hot water reaches a tap.

Plan Gas and Electrical Connections Early

If the home will use gas for hot water, cooking, heating or an outdoor barbecue point, decide early whether the supply will be natural gas or LPG. Availability, property location and intended appliances will influence the design. Gas pipework must be installed by a licensed gas fitter and sized for the combined demand of connected appliances.

It is worth thinking ahead. Even if you are only installing a cooktop now, a capped connection for a future outdoor kitchen or heater may be easier to provide during construction than after paving and landscaping are complete.

Plumbing also relies on coordination with electrical work. Heat pump hot water systems, pumps, rainwater controllers and some filtration equipment need suitable electrical supply. Clear communication between the builder, plumber, electrician and cabinetmaker prevents clashes and last-minute changes.

Approvals, Compliance and Qualified Work

New-build plumbing and gas work in Western Australia must meet applicable standards, local requirements and approval processes. Your builder and licensed trades should manage the relevant documentation, inspections and certificates for the work being completed.

For homeowners, the practical step is to ask what has been allowed for and what will be supplied at handover. This includes gas compliance paperwork where gas work is carried out, appliance details, warranty information and instructions for operating systems such as hot water, pumps or filtration.

Be cautious about reducing costs by removing items that are not visible. Quality pipework, correct drainage falls, compliant connections and proper testing are not optional extras. They are the foundation of a home that functions properly after the paint has dried.

Handover Checks for Your New Build Plumbing Guide

Before final handover, walk through the home with the plumbing works in mind. Turn on taps, flush each toilet, run showers and check that hot water reaches every fixture. Look under sinks and vanities for moisture, check that floor wastes drain properly and confirm outdoor taps are working.

Ask where the main water shut-off valve is located and make sure it can be reached quickly. Find out how to isolate the hot water system, where any rainwater pump controls are, and which taps are connected to tank, bore or mains water. If the property has a gas supply, identify the gas isolation point as well.

Keep photos of services before walls are lined and before landscaping is completed, along with copies of final plans and compliance documents. These records can save time if you renovate, install a pool, build a shed or need maintenance years later.

SmartFlow Plumbing & Gas works with South West homeowners and builders on practical new-build plumbing, gas, drainage and hot water solutions. The best time to raise a question is before the slab, wall lining or paving makes a simple adjustment difficult. A clear plan now gives your new home a better start and makes future maintenance far less of a headache.