Water Filter and Fridge Water Line Installation QLD 2026 - Complete Pricing Guide

Water Filter and Fridge Water Line Installation Costs in Queensland for 2026

The quality of treated municipal water supplied to Queensland homes by providers such as Urban Utilities (serving Brisbane, Ipswich, Lockyer Valley, Scenic Rim, and Somerset), Unity Water (serving the Sunshine Coast and Moreton Bay), and Gold Coast Water (serving the Gold Coast) meets the Australian Drinking Water Guidelines published by the National Health and Medical Research Council, but the journey from the treatment plant to the kitchen tap involves kilometres of pipe infrastructure of varying ages and materials, and the water that arrives at the tap may carry traces of chlorine disinfectant, sediment from aging mains and service pipes, and dissolved minerals that affect the taste, smell, and appearance without necessarily posing a health risk. Point-of-use water filtration systems address these quality factors by treating the water at the final stage of delivery, removing the residual chlorine taste, filtering the fine sediment, and in some cases reducing the dissolved mineral content to produce water that tastes cleaner and clearer than the unfiltered supply. The growing popularity of fridge models with built-in ice makers and water dispensers has added a secondary driver for residential water filtration, because these appliances require a permanent plumbed water connection and benefit from an inline filter that protects the fridge's internal water system from the sediment and scale that can clog the narrow internal passages and reduce the appliance lifespan.

The water filter market in Queensland spans a broad range of technologies, from simple single-cartridge carbon filters that cost less than $50 for the filter unit through to multi-stage reverse osmosis systems and whole-house filtration installations that represent a significant investment in the property's water infrastructure. The installation cost includes the filter system hardware, the plumbing connections to the cold water supply, the drainage connection (for systems that produce waste water, such as reverse osmosis), the mounting and positioning of the filter housing, and the initial commissioning and flushing of the system. For fridge water line installations, the cost is driven by the distance between the nearest cold water supply point and the fridge location, the pipe material and routing, and whether the installation includes an inline filter to protect the fridge.

Queensland's subtropical and tropical climate creates specific water quality considerations that influence the filtration system selection, including higher water temperatures (which can affect filter performance and bacterial growth in filter housings), seasonal variations in source water quality following heavy rainfall events, and the presence of naturally occurring minerals in some regional water supplies that are not removed by standard municipal treatment. Properties on tank water (rainwater) or bore water, which are common across rural and semi-rural Queensland where reticulated supply is not available, have additional filtration requirements because untreated rainwater can contain microbiological contaminants, sediment, and leaf tannins, while bore water may contain elevated levels of iron, manganese, hardness minerals, or other dissolved substances that affect taste and usability.

Under-Sink Water Filter Systems

Under-sink water filter systems are the most popular residential filtration choice in Queensland because they provide filtered drinking water at the kitchen sink without occupying bench space and without requiring modifications to the visible kitchen layout. The system consists of a filter housing mounted inside the under-sink cabinet, connected to the cold water supply line with a tee fitting, and feeding either through the existing kitchen tap (via a diverter valve) or through a separate dedicated filter tap mounted on the benchtop or sink. The dedicated tap approach is preferred because it allows the homeowner to use filtered water only when they want it (for drinking, cooking, and filling the kettle) while using the standard tap for tasks that do not require filtered water (rinsing dishes, filling mop buckets), which extends the filter cartridge life by reducing the volume of water processed.

The filter technology in an under-sink system ranges from a single activated carbon cartridge (which removes chlorine, sediment, and organic compounds that affect taste and odour) through to multi-cartridge systems that combine sediment pre-filtration, activated carbon, and additional specialised media for specific contaminant reduction. Single-cartridge carbon filter systems from brands like Puretec, Doulton, WaterCo, and 3M Aqua-Pure cost $150 to $350 for the filter unit and dedicated tap, with installation costing $150 to $300 for the plumbing connections and tap mounting. Twin-cartridge systems that add a sediment pre-filter cost $250 to $500 for the hardware and $200 to $350 for installation. The total installed cost for an under-sink filter system in Queensland ranges from $250 for a basic single-cartridge system with DIY-friendly connections (still requiring a plumber for the permanent pipe connection) through to $600 for a premium twin-cartridge system with a brushed nickel or matte black dedicated tap to match a modern kitchen aesthetic.

The ongoing cost of an under-sink filter system is the replacement cartridge, which costs $30 to $80 per cartridge depending on the brand and filtration level, and should be replaced every six to twelve months depending on the water quality and the volume of water filtered. A plumber can perform the cartridge replacement as part of a general plumbing maintenance visit, with the replacement service costing $80 to $200 including the cartridge and the labour. Many homeowners learn to replace the cartridges themselves after the plumber demonstrates the process during the initial installation, which reduces the ongoing cost to just the cartridge price. For properties undergoing a kitchen renovation, the under-sink filter installation is most efficiently performed during the plumbing rough-in stage, when the under-sink pipes are accessible and the additional connections can be made before the cabinet is installed.

Fridge Water Line Installation

The installation of a dedicated water line to a fridge with an ice maker and water dispenser is one of the most frequently requested small plumbing jobs in Queensland kitchens, driven by the widespread adoption of French-door and side-by-side refrigerators from brands like Samsung, LG, Fisher and Paykel, Westinghouse, and Electrolux that include these water features as standard. The fridge water line connects the cold water supply (typically at the kitchen sink connection or at a dedicated stop valve behind the fridge) to the water inlet on the rear of the fridge, using food-grade tubing that can be either braided stainless steel, copper, or polyethylene (PE) depending on the installation circumstances and the plumber's preference.

The simplest fridge water line installation occurs when the fridge is positioned next to or near the kitchen sink, because the cold water supply is readily accessible under the sink and the pipe run to the fridge is short. In this configuration, the plumber installs a tee fitting and a mini stop valve on the cold water supply under the sink, runs the tubing along the back of the cabinetry or through the cabinet backs to the fridge location, and connects the tubing to the fridge's water inlet. This installation costs $200 to $350 including the fittings, tubing, and labour. When the fridge is located further from the nearest water supply point (for example, on the opposite side of the kitchen or in an adjoining room), the pipe run is longer and may require penetrations through cabinet backs, walls, or floors, which increases the cost to $350 to $500.

An inline water filter on the fridge water line is a recommended addition that costs $30 to $80 for the filter and $50 to $100 for the additional installation work. The inline filter reduces the sediment and chlorine reaching the fridge's internal water system, which protects the narrow internal tubing, the solenoid valve, the ice maker mechanism, and the water dispenser from the scale buildup and blockages that can cause premature failure of these components. Samsung and LG recommend filtered water for their fridges with ice makers, and an inline filter on the supply line provides this without requiring a separate under-sink filter system. The inline filter cartridge should be replaced every six to twelve months, and the replacement cartridge costs $15 to $40 depending on the filter brand and type. For properties undertaking a complete laundry plumbing or kitchen renovation, the fridge water line is most efficiently installed during the plumbing rough-in when all pipe runs are accessible.

Reverse Osmosis Systems

Reverse osmosis (RO) is the most thorough point-of-use water purification technology available for residential installation, using a semi-permeable membrane to remove up to 99 percent of dissolved solids, heavy metals, microbiological contaminants, and chemical compounds from the water supply. An RO system is a multi-stage filtration system that typically includes a sediment pre-filter (to protect the membrane from particulate damage), an activated carbon pre-filter (to remove chlorine that would degrade the membrane), the RO membrane itself (where the primary purification occurs), and a post-filter (usually activated carbon) to polish the taste of the purified water before it reaches the tap. The purified water is stored in a pressurised tank under the sink and delivered through a dedicated RO tap on the benchtop.

RO systems installed in Queensland homes cost $500 to $1,200 fully installed, with the variation reflecting the system quality, the number of filtration stages, the brand, and the installation complexity. Systems from Puretec, WaterCo, Aquasafe, and Pentair are commonly installed across Queensland, with product selection based on the water quality, the daily volume requirement, and the under-sink space available. A standard four-stage RO system costs $300 to $600 for the hardware and $200 to $400 for installation, while a premium five or six-stage system with a remineralisation cartridge (which adds beneficial minerals back to the water after the RO membrane strips them out) costs $500 to $800 for hardware and $300 to $500 for installation. The remineralisation stage is increasingly popular because pure RO water has a flat taste that some people find unpleasant, and the added minerals restore a pleasant mineral character to the water.

One important consideration for RO systems is the waste water ratio, because the reverse osmosis process produces both purified water and a concentrate stream (waste water) that carries the rejected contaminants to the drain. A standard residential RO system produces approximately three to four litres of waste water for every one litre of purified water, which represents a significant water consumption overhead in a state where water conservation is valued and where properties on tank water have a finite supply. Higher-efficiency RO systems with 1:1 or 2:1 waste ratios are available at a premium cost, and these systems are recommended for Queensland properties where water conservation is a priority or where the supply is limited. The waste water drain connection requires a plumbing connection to the kitchen sink drain or a dedicated drain line, which the plumber installs as part of the RO system installation.

Whole-House Filtration Systems

Whole-house filtration systems (also called point-of-entry systems) treat all the water entering the property, providing filtered water to every tap, shower, appliance, and outdoor connection. The system is installed on the main water supply line after the water meter, typically in an outdoor enclosure or a utility area, and the water passes through the filter stages before entering the property's internal pipe system. Whole-house systems are particularly popular in Queensland for properties with noticeable sediment in the water supply (common in areas with older pipe infrastructure), properties where the water hardness causes scale buildup in hot water systems, kettles, and shower screens, and properties on tank water or bore water where comprehensive treatment of the entire supply is needed.

The cost of a whole-house filtration system depends on the number of filtration stages, the filter capacity (which determines the flow rate and the filter life), and the specific water quality issues being addressed. A basic whole-house sediment and carbon system that removes particulate matter and chlorine costs $800 to $1,500 installed, using twin Big Blue filter housings (a standard 20-inch or 10-inch large-diameter housing) with a sediment cartridge and an activated carbon cartridge. A more comprehensive system that adds water softening (for hard water areas), iron and manganese removal (for bore water), or additional specialised media costs $1,500 to $3,000 installed. Brands commonly used for whole-house systems in Queensland include Puretec, WaterCo, Pentair, and Aquasafe, with system sizing based on the property's water flow rate and the number of bathrooms.

The ongoing maintenance cost for a whole-house system is higher than for a point-of-use system because the filter cartridges process a much larger volume of water (the entire household consumption rather than just the drinking water volume) and need replacement more frequently. The cartridges for a twin Big Blue system cost $80 to $150 per set and should be replaced every six to twelve months depending on the water quality and consumption, with a plumber's replacement service costing $150 to $300 per visit. Some whole-house systems use self-cleaning or backwashing filter media that extends the maintenance interval but at a higher initial system cost. For properties with hot water systems that suffer from scale buildup, a whole-house system with a scale-inhibiting cartridge can extend the hot water system's life and improve its efficiency by reducing the mineral deposits inside the tank and on the heating element.

UV Water Treatment Systems

Ultraviolet (UV) water treatment is a disinfection technology that destroys bacteria, viruses, and other microbiological contaminants by exposing the water to UV light at a specific wavelength (254 nanometres) as it passes through a treatment chamber. UV treatment does not remove sediment, chemicals, or dissolved minerals from the water, so it is typically installed in combination with a sediment filter and an activated carbon filter to provide comprehensive treatment. The primary application for UV treatment in Queensland is on properties using rainwater tanks or bore water as their drinking water supply, where the water has not been treated by a municipal treatment plant and may contain harmful microbiological contaminants including E. coli, Cryptosporidium, and Giardia that can cause gastrointestinal illness.

UV treatment systems for residential use cost $400 to $1,000 installed, with the variation reflecting the system flow rate capacity, the UV dose (measured in millijoules per square centimetre), and the installation complexity. The UV chamber is installed on the water supply line after the sediment and carbon pre-filters (because sediment and turbidity in the water can shade microorganisms from the UV light and reduce the treatment effectiveness), and it operates continuously whenever water is flowing through the system. The UV lamp has a service life of approximately 9,000 to 12,000 hours (roughly 12 months of continuous operation), and the annual lamp replacement costs $80 to $150 for the lamp plus $50 to $100 for the plumber's replacement service. Brands commonly installed in Queensland include Puretec, Steriflow, Viqua (Trojan Technologies), and UV Guard, with system sizing based on the maximum flow rate required.

For Queensland properties on tank water, the combination of a sediment filter, an activated carbon filter, and a UV treatment system provides a comprehensive treatment train that addresses the main water quality risks: sediment from roof runoff and tank deposits, organic compounds and taste issues from leaf matter and tannins, and microbiological contamination from animal droppings, insects, and other sources that can enter the tank via the roof catchment. The total cost of a combined sediment, carbon, and UV system for tank water treatment ranges from $800 to $2,000 installed, and the annual maintenance cost (filter replacements and UV lamp) ranges from $150 to $350. Our plumbing services guide covers the broader plumbing considerations for properties on tank water.

Queensland Water Quality Considerations

The water quality across Queensland varies significantly by region and by the source of the water supply, and understanding the specific water quality characteristics in your area is essential for selecting the appropriate filtration system. South East Queensland's water supply is drawn primarily from dams including Wivenhoe, Somerset, North Pine, Hinze, and Little Nerang, treated at modern treatment plants, and distributed through the SEQ Water Grid managed by Seqwater. The treated water is of high quality, but the residual chlorine used for disinfection (which is necessary to maintain water safety through the distribution network) and the sediment that accumulates in aging distribution pipes are the primary drivers of filtration demand in the SEQ area. The Urban Utilities water quality reports for Brisbane and surrounding areas show consistent compliance with the Australian Drinking Water Guidelines, with occasional elevated turbidity following heavy rainfall events.

Regional Queensland water supplies vary more widely in quality depending on the source (surface water, bore water, or desalinated water) and the treatment level. Townsville's water supply from the Ross River Dam and Paluma Dam occasionally experiences taste and odour events related to algal activity in the source water, which standard carbon filtration addresses effectively. Cairns' water supply from Copperlode Falls Dam is generally of good quality but the warmer water temperature in the tropical North accelerates the chlorine decay in the distribution system, which can result in lower residual chlorine levels and a slightly different taste profile compared to SEQ water. Central Queensland and Western Queensland towns may rely on bore water or surface water with higher mineral content, hardness, and dissolved solids that benefit from more comprehensive filtration including softening and reverse osmosis.

The Queensland Health department publishes guidance on drinking water quality and regulates the water quality provided by registered water suppliers across the state. The Queensland Department of Environment and Science oversees the environmental aspects of water quality including source water protection and catchment management. For homeowners uncertain about their water quality, a water quality test can be arranged through a NATA-accredited laboratory for $50 to $200 depending on the parameters tested, and the results can guide the filtration system selection to target the specific contaminants or quality issues present in the supply.

Tank Water and Bore Water Filtration

A substantial number of Queensland properties, particularly in rural, semi-rural, and acreage areas outside the reticulated water supply networks, rely on rainwater tanks or bore water as their primary water source. These untreated water sources have different filtration requirements compared to treated municipal water, and the filtration system must address the specific contaminants present in the raw water. Rainwater collected from roof catchments in Queensland typically contains sediment (from dust, pollen, leaf matter, and insect debris), organic compounds (from leaf tannins and decomposing matter in the gutters and tank), and microbiological contaminants (from bird and animal droppings, insects, and airborne organisms that enter the tank via the roof catchment). The filtration system for tank water should include sediment filtration (to 1 micron or finer), activated carbon filtration (for taste, odour, and organic compound removal), and UV disinfection (for microbiological safety).

Bore water in Queensland can contain elevated levels of iron (which causes orange staining of fixtures and laundry), manganese (which causes black staining), hardness minerals (calcium and magnesium, which cause scale buildup), dissolved salts, and in some areas naturally occurring fluoride, arsenic, or nitrate at levels above the drinking water guidelines. The filtration system for bore water is tailored to the specific contaminants identified in a water quality test, and may include iron and manganese removal (using oxidation and filtration media such as Birm, Greensand, or Filox), water softening (using ion exchange resin), and reverse osmosis (for dissolved salt and mineral reduction). A comprehensive bore water treatment system costs $2,000 to $5,000 installed depending on the contaminants, the flow rate, and the treatment stages required. For properties with bore water used for irrigation and garden watering, the outdoor supply can often be fed from the bore without treatment while the indoor supply is treated for drinking water quality.

Filter Maintenance and Ongoing Costs

The ongoing cost of a water filtration system is determined by the filter cartridge replacement frequency, the cartridge cost, and whether the homeowner performs the replacement or engages a plumber. Under-sink carbon filters cost $30 to $80 per cartridge and should be replaced every six to twelve months, with the replacement interval depending on the water quality and the volume filtered. Reverse osmosis systems have multiple cartridges on different replacement schedules: the sediment pre-filter and carbon pre-filter are replaced every six to twelve months ($20 to $40 each), the RO membrane is replaced every two to three years ($80 to $150), and the post-filter is replaced annually ($20 to $40). Whole-house filter cartridges cost $80 to $150 per set for a twin housing system and should be replaced every six to twelve months. UV lamps are replaced annually at a cost of $80 to $150 per lamp.

The importance of maintaining the filter replacement schedule cannot be overstated, because a filter cartridge that is left in service beyond its recommended life becomes less effective at removing contaminants, can develop bacterial growth within the filter media (particularly in Queensland's warm climate where the under-sink temperatures promote bacterial proliferation), and can actually degrade the water quality rather than improving it. A carbon filter that has exhausted its adsorption capacity may begin releasing the contaminants it previously captured back into the water, and a sediment filter that is clogged with debris restricts the water flow and creates pressure differentials that can damage downstream components. Setting a calendar reminder for filter replacement and combining the replacement with other routine plumbing maintenance is the most reliable approach to maintaining the system's performance.

Licensing, Standards, and Compliance

Water filter and fridge water line installations that involve a permanent connection to the mains water supply, a connection to the drainage system, or any modification to the property's plumbing system must be performed by a licensed plumber in Queensland. The Queensland Building and Construction Commission licenses plumbers and oversees compliance with the plumbing standards. All plumbing work must comply with AS/NZS 3500 (the Plumbing and Drainage Code) published by Standards Australia, and the water supply components (fittings, valves, and filter housings) should carry the WaterMark certification that confirms they meet the Australian performance requirements. The WaterMark certification scheme ensures that plumbing products in contact with drinking water are safe and fit for purpose, and a plumber who installs non-WaterMark certified products may be in breach of the plumbing regulations. Consumer protection under Australian Consumer Law, enforced by the Australian Competition and Consumer Commission, applies to filter products and installation services.

Saving Money on Water Filtration

The biggest ongoing cost of water filtration is cartridge replacement, and choosing the right system for your actual water quality needs avoids paying for filtration capacity you do not need. If your Queensland home is on town water and your primary concern is chlorine taste and odour, a single-stage carbon filter ($250 to $450 installed) with cartridge replacements at $30 to $60 every six to twelve months is all you need and delivers excellent taste improvement at the lowest ongoing cost. Installing a reverse osmosis system ($500 to $1,200) for town water that only needs taste improvement wastes 3 to 4 litres of water for every litre of filtered water produced and requires more expensive membrane replacements ($80 to $150 every two to three years) in addition to the carbon pre-filter and post-filter cartridges, adding $100 to $200 per year to the running cost for no meaningful improvement in water quality beyond what the carbon filter already provides. Reserve reverse osmosis for situations where the water supply has elevated dissolved solids, specific contaminants that carbon cannot remove, or where the water is from a bore with mineral content that affects taste and appliance performance.

Buying replacement cartridges in multi-packs (typically 4 to 6 cartridges) saves 20 to 30 percent compared to buying individual cartridges, and most reputable filter brands sell annual or bi-annual cartridge kits that include all the filters needed for a complete service at a bundled price. Some plumbers offer annual filter service plans at $120 to $250 per visit that include the replacement cartridges, labour, and a system check, which is convenient but typically costs $30 to $80 more per year than buying the cartridges yourself and changing them (which is a simple DIY task on most under-sink systems that takes 5 to 15 minutes following the manufacturer's instructions). If you are installing a new under-sink filter, choose a system that uses standard-sized cartridges (10-inch or 20-inch industry standard housings) rather than proprietary cartridges, because standard cartridges are available from multiple manufacturers at competitive prices, while proprietary cartridges lock you into buying from a single supplier at whatever price they set.

Water Filter Considerations for Queensland House Types

The type of Queensland home you live in influences the best filtration approach. Stumped Queenslander homes with the water meter and main shutoff valve at the front boundary and the kitchen at the rear of the house have long pipe runs that can accumulate sediment and biofilm, making a point-of-use filter at the kitchen tap more effective than relying solely on the water quality at the meter. The subfloor space on a stumped home provides convenient access for installing a whole-house filter system on the main supply pipe where it enters beneath the house, with the filter housing mounted to the bearers or joists for easy cartridge access. Slab-on-ground homes typically have the water supply entering through the slab near the front of the house, and a whole-house filter can be installed on the supply pipe at the point of entry before it branches to the various fixtures. For apartments and townhouses on the Gold Coast and in Brisbane where the water passes through a building's common supply system before reaching the individual unit, a point-of-use filter at the kitchen tap is the practical choice because the resident has no access to modify the common supply plumbing.

Red Flags in the Water Filter Industry

The water filter industry in Australia includes some operators who use high-pressure sales tactics and exaggerated health claims to sell overpriced systems to homeowners who do not need them. Be cautious of any water filter company that cold-calls, door-knocks, or sends unsolicited letters claiming your water is dangerous or contaminated, because Queensland town water supplied by Urban Utilities, Unity Water, and regional council water providers meets the Australian Drinking Water Guidelines and is safe to drink without additional filtration. Free water testing offered by filter companies at your door or at shopping centre displays is a sales tool, not an independent assessment, and the "test results" are often presented in a way that exaggerates the significance of normal, safe levels of minerals and chlorine. A legitimate water quality concern should be investigated through an independent NATA-accredited laboratory test ($50 to $200) that provides objective results you can take to any filter supplier for an unbiased recommendation. Never sign a contract or finance agreement for a water filter system on the spot, and always obtain a second quote from an independent plumber who does not represent a specific filter brand.

Regional Water Filter Costs Across Queensland

Water filter and fridge water line installation costs are relatively consistent across urban Queensland, with Greater Brisbane, the Gold Coast, and the Sunshine Coast offering the most competitive pricing due to the larger number of plumbers and the concentrated market. Under-sink filter installation in SEQ costs $250 to $550, fridge water line connections cost $200 to $450, and whole-house systems cost $800 to $2,500. Regional Queensland centres including Toowoomba, Townsville, Cairns, Mackay, and Rockhampton have plumber rates that are typically 10 to 20 percent above SEQ, reflecting longer travel distances and smaller local markets. However, regional Queensland often has higher demand for comprehensive filtration (whole-house systems, UV treatment, bore water treatment) because of the more variable water quality and the higher proportion of properties on tank water or bore water.

For water leak detection on filtered water systems, the inline nature of the filter installation means that any leak at the filter connections or fittings can cause significant water damage to the under-sink cabinet and kitchen flooring if not detected early. Installing a leak detection sensor or a drip tray under the filter housing is a low-cost precaution ($20 to $50) that can prevent thousands of dollars in water damage. Our burst pipe repairs guide covers the broader topic of pipe and fitting failures that can affect any part of the plumbing system.

What to Look Out For in Water Filter and Fridge Line Quotes

A water filter installation quote should specify the filter system brand and model, the number of filtration stages, the filter technology (carbon, sediment, RO, UV), the dedicated tap brand and finish (for under-sink systems), the pipe material and routing for the connections, and the total installed cost including all fittings and commissioning. The quote should also indicate the estimated ongoing filter replacement cost and schedule, so you can factor the total cost of ownership into your decision rather than just the upfront installation cost. Ask whether the plumber supplies and installs a specific brand or whether they can install a system you have purchased, as some plumbers prefer to supply the system (which gives them control over the product quality and warranty) while others are happy to install customer-supplied equipment.

For fridge water line quotes, confirm that the quote includes the stop valve (so the water supply to the fridge can be isolated for servicing or fridge replacement), the appropriate food-grade tubing, and an inline filter if recommended. The pipe route should be discussed during the quoting process, because the most direct route may not be the most practical if it requires penetrations through load-bearing cabinetry or creates a trip hazard, and an alternative route that is slightly longer but uses existing cavity spaces or pipe chases may be a better solution.

Post your water filter or fridge water line installation on The Quote Yard to connect with licensed plumbers across Queensland. For related services, our plumbing services guide covers general plumbing costs, our hot water system guide covers hot water systems that benefit from filtered supply water, our bathroom renovation plumbing guide covers filtered water taps in new bathrooms, our blocked drains guide covers drainage issues including RO waste water connections, and our gas fitting guide covers gas appliance connections in the kitchen.

Ask the quoting plumber to specify the filter system brand and model, the number of filtration stages, the cartridge type and expected replacement frequency, the ongoing cartridge cost per year, and whether the system uses standard-sized cartridges or proprietary cartridges that can only be purchased from the manufacturer. A filter system quoted at $450 installed with cartridges that cost $120 per year is a better long-term investment than a system quoted at $350 with cartridges that cost $200 per year. For fridge water line installations, confirm that the quote includes a dedicated isolation valve for the fridge line ($20 to $40 for the valve) so the fridge supply can be shut off independently without affecting the rest of the kitchen plumbing, and check whether the plumber uses 10mm copper pipe or braided stainless steel hose (both are acceptable, but plastic tubing without a braided jacket is a leak risk that should not be used in a concealed location). Be cautious of filter companies that offer "free installation" with the purchase of their filter system, because the system price is typically inflated by $200 to $400 to cover the installation cost, and the installer may not hold a QBCC plumbing licence, meaning the work has no consumer protection and may not comply with AS/NZS 3500 requirements for potable water connections.