A renovation is the right time to replace an irrigation network that leaks, waters paths or no longer matches the garden. New paving, extensions, retaining walls and planting can make old pipe routes inaccessible, so the system should be redesigned before finished surfaces close the ground.
The goal is not more sprinklers. It is controlled water delivery to plants with similar needs, using serviceable routes and simple controls the household will actually adjust. Local water restrictions, climate and approved products must be checked for the property.
Start with a garden and water-use brief
Map retained trees, new beds, lawn, pots, productive planting and areas that will not be irrigated. Record sun, wind, soil, slope and roof runoff. Different exposures can make identical plants demand different watering patterns.
Australian Government Your Home outdoor-water guidance encourages climate-suitable planting, efficient application and attention to soil and mulch. Use those principles to reduce demand before sizing pipes or buying controls.
Decide who operates the system, how often they are away and how much manual observation they will provide. A sophisticated controller is poor value if no one reviews broken emitters or seasonal settings.
Audit the existing network before demolition
Locate the connection, isolation, backflow arrangement, controller, valves, filters, pressure controls, pipes, sprinklers, drippers and sleeves. Run each zone with a suitable irrigation professional and note leaks, blocked outlets, mixed application types and poor coverage.
Compare visible routes with plans and use careful investigation where lines disappear. Do not assume abandoned pipe is empty or harmless near excavation. Mark all known services before landscaping machinery arrives.
Record which components are serviceable and compatible with a new design. Reuse should be based on condition and performance, not a desire to avoid one replacement valve.
A related guide to consider while planning this work is Retrofitting Greywater Reuse: What an Existing Home Needs.
Coordinate the design with the renovation plan
Overlay building footings, drainage, electrical routes, gas, water, sewer, pool equipment, paving, decks and tree protection zones. The irrigation route should avoid conflicts and preserve access for other services.
Install sleeves beneath new paths or paving where the designed network needs to cross. Their positions and contents should be recorded from fixed reference points. An empty future sleeve can be useful where the garden layout is likely to change.
Sequence main routes after heavy excavation but before base preparation and finishes. Protect installed pipe from construction traffic and prevent open ends filling with soil.
Divide zones by plant need and delivery method
Group areas that need similar watering duration, frequency and application. Lawn sprinklers should not normally dictate the programme for a mulched shrub bed. Pots, vegetables, established trees and new planting may each warrant a distinct approach.
Also consider pressure, elevation and available flow. An irrigation designer should test the supply and design zone demand rather than adding outlets until performance declines. Do not mix incompatible emitters on convenience alone.
Label zones by place and purpose, such as “north lawn” or “kitchen beds”, rather than numbers only. Clear naming helps future adjustment and fault finding.
Give establishment watering an exit plan
New plants may need different care from established landscaping. Design temporary or adjustable elements so establishment watering can be reduced or removed rather than becoming the permanent default.
Keep mature trees out of the lawn schedule
Have an arborist or landscape professional advise on significant trees. Their root area and watering response cannot be inferred from a turf cycle, and trenching may damage the very canopy the renovation aims to keep.
Choose spray, rotor or drip application deliberately
Spray and rotor systems can suit defined lawn areas when designed for consistent coverage and kept off buildings and paths. Drip can target beds and reduce overspray, but its emitters, filters and lines still require inspection.
Match application to soil infiltration and slope. Water delivered faster than soil accepts it becomes runoff regardless of controller intelligence. Divide watering into suitable cycles if advised, and improve soil and mulch where appropriate.
Avoid placing outlets where plants will quickly block them or mowers will strike them. Show edge details and final garden levels on the installation plan.
Select pipework as a documented system
Vinidex information confirms polyethylene systems are used across irrigation and water applications, but material suitability, dimensions, pressure class and jointing depend on the selected system. Obtain current manufacturer and designer specifications.
Use compatible fittings and make joints accessible where the design requires maintenance. Protect pipes from ultraviolet exposure, vehicle loading, heat and sharp backfill as appropriate. Do not embed an unidentified mixture of leftover fittings.
Pressure test and flush the system according to the design before emitters are commissioned and before hard landscaping conceals routes. Record test results.
Protect the house from irrigation water
Keep sprays away from walls, subfloor vents, doors, windows and service equipment. Check wind drift at normal operating times. Repeated wetting can stain finishes and add moisture near the building.
Raised beds and changed ground levels require separate moisture and inspection detailing. Irrigation should not discharge into termite inspection zones or against slab edges. Ask the building professional to mark protected clearances.
For more detail on this part of the project, see Raised Garden Beds Beside a House: Moisture and Inspection Clearances.
Position garden taps and quick-connect points so hoses do not drag across thresholds. Licensed plumbing work and backflow requirements must be confirmed for the jurisdiction and water provider.
Use rainwater only through a designed arrangement
If a tank supplies irrigation, document storage, pump, filters, controls, top-up arrangement and overflow. Match zone demand to realistic available water rather than assuming the tank is always full. Preserve safe access for pump and filter service.
Clearly identify water sources and prevent inappropriate cross-connections through licensed design. Controller logic should respond sensibly when stored water is unavailable. Any mains support must meet current local requirements.
Coordinate tank overflow with the stormwater plan. The irrigation upgrade should not solve garden watering while creating ponding beside the house.
Choose controls for understandable operation
A controller should allow seasonal adjustment, individual zone programming and manual testing. Weather or soil inputs can help, but their location, calibration and fallback behaviour matter. Basic operation should remain possible without a third-party app.
Place the controller where it is protected yet accessible, with a clear zone chart. Provide a licensed electrician for any mains electrical work. Battery devices and low-voltage cabling still need suitable installation and maintenance.
Agree who updates schedules after planting establishes. Set a calendar reminder for review rather than leaving the first programme unchanged for years.
Place valves and filters where they can be serviced
Group components logically while avoiding a pit so crowded that nothing can be removed. Keep lids visible, stable and clear of mulch. Do not locate a valve box beneath a future deck post, fixed barbecue or heavy planter.
Provide isolation that allows one section to be repaired without disabling the entire garden where the design supports it. Label flow direction and zones. Retain spare compatible parts if the supplier recommends them.
Filters and pressure components only work when maintained. Include their cleaning and replacement instructions in handover.
Account for slope, erosion and drainage
Observe where water flows after irrigation and rain. On slopes, place and operate outlets to limit runoff and soil loss. Stabilise disturbed trenches and protect retaining-wall drainage.
Your Home’s stormwater guidance supports reducing concentrated runoff and keeping site water paths coordinated. Irrigation should supplement planting without regularly feeding grated drains.
Correct low points created by trench settlement before final planting. A leaking buried pipe may reveal itself as one persistently wet patch; ensure the area remains inspectable.
Design around pets, mowing and play
Place pop-ups and valve lids outside repeated wheel and foot paths where practical. Protect exposed tubes from chewing and garden tools. Avoid fine spray across children’s play surfaces or outdoor dining.
Use edge details that let mowers pass without hitting outlets. A clean strip or correctly placed head can reduce repeated damage. Verify coverage after turf and edging reach final levels.
Keep controller wiring and pump equipment secure but serviceable. Household safety and technician access should both be considered.
Prepare a measured irrigation schedule
Commission each zone after planting. Check coverage, emitter flow, leaks and runoff, then set an initial programme based on landscape advice and current local restrictions. Record the assumptions and revisit them through seasons.
Use observation of soil and plants rather than watering by habit. Shut down or reduce zones after establishment where appropriate. Repair leaks promptly; a controller cannot distinguish all faults from demand.
Keep a simple log of changes. It helps diagnose whether a dry bed reflects programming, blockage, pressure or plant choice.
Budget the network in AUD by component
Separate design and testing, demolition, sleeves, mainline, valves, zones, emitters, controller, tank integration, electrical work, reinstatement and commissioning. Confirm AUD and GST treatment and define the landscaped area included.
For hypothetical arithmetic only, assume design and testing are A$2,500, pipework and valves A$7,500, application equipment A$5,000, controls A$2,000 and reinstatement A$3,000, all including GST. The invented total is A$20,000. It is not a current market price or quote.
Compare quotes using zone plans and component schedules. A cheaper system with fewer accessible valves or no commissioning is not equivalent.
Keep a practical manual-watering fallback
Automation should not remove the ability to care for a new tree, isolated pot or repaired bed by hand. Position taps or approved connection points so a hose reaches without crossing the main doorway or dragging through delicate planting. Store it where it drains and does not become a trip hazard.
Document how the irrigation supply is isolated while household water remains available, where the pump can be bypassed if designed, and whom to call for faults. Do not improvise cross-connections or open a controller enclosure during a failure.
A manual check is also the best way to notice blocked emitters and plant stress. Walk the zones periodically even when weather-responsive controls report normal operation.
Write a scope that competing installers can price
Issue a plan with zone boundaries, intended application type, pipe and sleeve routes, valve locations, controls, water source, retained components and reinstatement areas. State testing, flushing, labelling, programming and training obligations. Ask tenderers to identify substitutions before installation.
Clarify who excavates near structures and trees, who coordinates other services and who repairs paving or turf. Set a process for concealed obstructions rather than accepting unrecorded route changes. Require current product information for major components and compatible joints.
At contract review, compare coverage and serviceability as well as component count. More outlets do not demonstrate a better design, and fewer zones may combine plants whose needs cannot be reconciled.
Leave capacity for a changing garden
Gardens mature, lawns become beds and an extension may occupy a former zone. Use labelled isolation and accessible branch points where the designer considers them useful. Do not oversize or overcomplicate the installed system on a vague promise of future use.
Keep one accurate as-built plan in the controller cabinet and another with house records. Dimension sleeves and valve boxes from permanent walls or boundaries, since plants and garden edging will move.
When the landscape changes, review the water brief rather than adding an emitter to the nearest tube. A deliberate small alteration protects pressure, programming and the logic of the wider network.
Use installation hold points
- Map retained planting, services, structures and final surface levels.
- Approve supply testing, pipe routes, sleeves and zone logic.
- Inspect joints and pressure testing before backfilling.
- Record valves, sleeves and pipes before paving or planting.
- Commission every outlet at final landscape levels.
- Hand over the zone chart, schedules and maintenance tasks.
Run the finished network while the irrigation designer and landscaper are present. Watch boundaries, walls, paths and drains, not only the plants. Correct overspray, misting, pooling and inaccessible components before final payment.
A strong replacement system disappears into the garden but not from the owner’s understanding. Its zones follow plant needs, its pipes avoid future conflicts and its controls invite seasonal adjustment. That is far more valuable than simply replacing every old sprinkler with a new one.
Reference basis: Australian Government Your Home, Outdoor Water Use; Australian Government Your Home, Landscaping and Garden Design; Vinidex, PE Systems; Australian Government Your Home, Stormwater.