Ducted Air Conditioning Installation Costs ACT 2026 - Get Free Quotes

Ducted Air Conditioning Costs in the ACT

A ducted install in the territory sits at $12,000 to $18,000 for a single storey home with four or five zones, $18,000 to $25,000 for a larger home with six to eight, and $20,000 to $32,000 where the house is two storey or the roof space is awkward. Capacity, zone count and roof space conditions explain the bulk of the difference.

The comparison most households make is the least useful one. Quotes get lined up against each other on brand, indoor unit capacity and outdoor unit model, because those are the concrete specifications printed on the page, and the equipment across the established manufacturers is genuinely similar at a given capacity. The ductwork is another matter entirely.

It is designed for your house by the person quoting, and the quality of that design is what you will live with.

Think of a ducted system as two things sold together. There is the refrigeration equipment, which is manufactured, warranted and largely interchangeable, and there is the air distribution system, which is built on site from the installer's judgement about duct sizes, run lengths, outlet positions, return air and zoning. Only the second of those is designed for your house specifically.

It is also the part that decides whether a bedroom at the end of the house is comfortable in July.

Canberra loads the design differently from most Australian cities. Heating is the dominant demand here rather than cooling, warm air behaves differently in a room from cool air, and a duct layout that performs well cooling a Brisbane house may distribute heat poorly in a Canberra winter. That difference has practical consequences for outlet placement and sizing. Where a fault later appears in the ductwork or plant, an electrical fault finding specialist rules out the supply side first.

Below: what the installation actually involves, whether your roof space can take it, duct sizing and insulation, return air, outlet placement, zoning design, converting from ducted gas heating, capacity calculation, and how to read quotes that all look similar on the front page.

One idea is worth carrying through the whole subject. A ducted system is the most expensive appliance most households will install, it will be in the ceiling for fifteen years or more, and almost nothing about the air distribution can be changed afterwards without opening the building up again. The equipment can be replaced later.

The ductwork, the outlet positions and the return air are decisions you make once.

What the Job Involves

A ducted installation is a building job as much as a refrigeration one. The indoor plant is positioned and supported in the roof space or occasionally under the floor, ducting is run to each outlet, ceiling outlets and a return air grille are cut in, the outdoor unit is positioned and connected by refrigerant pipework, the electrical supply is run and connected, and the whole system is commissioned and balanced. Several trades put hands on it. Coordination is part of what you are paying for. A business that subcontracts the electrical work should still carry responsibility for the finished result. Ask who holds the job together if something goes wrong between trades.

Design should come before any of that and it is the step most compressed. A proper design calculates the heating and cooling load for each space, determines total capacity, sizes each duct run for the airflow it must carry, positions outlets for effective distribution, sets the return air size, and works out zone groupings that reflect how the household lives. A day spent on design saves years of complaint. Request see the layout before you accept anything.

Installation itself usually takes two to four days for a domestic system. Roof space work occupies the bulk of it, ceiling penetrations and outlet fitting create some mess that should be protected against and cleaned up, and the electrical and refrigeration connections come toward the end. Expect some disruption to the house. A good installer tells you which days are which. Roof space work generates dust that finds its way through ceiling penetrations. Covering furniture in the affected rooms beforehand is worth the effort.

Commissioning and balancing close the job and are frequently skipped. Once running, the airflow to each outlet should be checked and adjusted so no room is starved and none is overserved, the zone dampers should be verified, the refrigerant charge confirmed against specification, and the system's performance measured rather than assumed. An unbalanced system generates precisely the complaints that get blamed on capacity. A general installation specialist handles split systems where ducted is not viable.

Documentation belongs in the handover. The design layout, the equipment models and serial numbers, the commissioning readings, the electrical certificate where issued, the zone plan and both warranties should all come to you at completion. Keep the lot together somewhere retrievable. Any technician attending in ten years will thank you for the duct layout alone.

Access for future servicing should be considered at design stage rather than discovered later. The plant needs enough clearance around it for filters, coils and components to be reached, the manhole giving entry to the roof space should be usable rather than token, and a system installed in a position nobody can comfortably work in will be serviced badly for its entire life. Ask how a technician reaches the plant. The answer affects every service visit for the next fifteen years. A cramped plant position also raises the labour on every future repair. Nobody thinks about that on installation day.

Roof Space Feasibility

Not every Canberra house suits ducted, and finding out early saves money. The roof space must have enough height and clear run to accommodate the plant and the ducting, the pitch determines how far toward the eaves a person can physically work, and trusses restrict where ducts can pass in ways that traditional rafters do not. Shallow pitch is the usual obstacle. An installer who has not been into your roof space cannot tell you whether it works.

Existing roof space contents complicate more Canberra jobs than people expect. Solar inverters and cabling, water tanks, old evaporative ducting, insulation batts that must be moved and reinstated, and television or communications wiring all occupy space and constrain duct routing. Insulation disturbed during installation should be put back properly. Ask specifically what happens to the ceiling insulation where ducts cross it. Batts left folded back after installation quietly cost you every winter.

Insist on a roof space inspection during the quote. The installer should get into the cavity, check the height at the plant position, confirm there is a path for the main trunk duct, look at the truss layout and note any obstructions such as existing ductwork, water tanks, solar inverters or wiring runs. A quote written without that inspection carries assumptions. Assumptions become variations once the job starts.

Where the roof space genuinely cannot take it, alternatives exist. Under floor installation suits some raised houses, bulkheads can carry ducting through parts of a home at the cost of ceiling height, and a well-planned combination of splits or a multi-head system sometimes delivers a better result than forcing ducted into an unsuitable building. Forcing ducted into an unsuitable house produces a compromised system. An honest installer will tell you when the house is not a candidate. That conversation is worth more than a quote for a system that will never quite work. Walking away from an unsuitable job is a mark of a good operator. It is also rare enough to be worth noticing.

Two storey homes need the path to the lower level resolved before anything else. Ducting has to travel down through a cupboard, a bulkhead, a wardrobe or a purpose-built chase, that route must be found and agreed at quoting stage, and the loss of storage or ceiling height is a real trade-off worth understanding upfront. Ask exactly where that drop will run. It is easily the most common surprise on a two storey ducted job.

Duct Sizing and Insulation

Ductwork that is too small throttles a correctly sized unit, and this is the most common hidden defect in domestic installations. Air moving through a duct meets resistance, undersized ducting raises that resistance sharply, and the result is reduced airflow, poor distribution to distant rooms, higher running costs and a fan working harder than it should for its whole life. The unit is not at fault in that scenario. The path you gave the air is.

Noise is largely a function of duct sizing and outlet velocity. Air forced through undersized ducting or a small outlet moves faster and makes more noise, generously sized ducting and outlets move the same volume quietly, and a system that whistles or rushes at the outlets is usually telling you something about its design rather than its manufacture. Quiet operation is a design outcome. Put the question of what outlet velocity the design targets in bedrooms. Bedrooms are where noise is noticed and least tolerated. A living area tolerates far more air movement than a bedroom does.

Run length and layout matter as much as diameter. Long runs, tight bends, crushed sections where a duct passes a truss, and ducting left to sag between supports all add resistance, and a layout with the plant central to the house performs better than one where air must travel the length of the building to reach the far bedrooms. Plant position is a design decision rather than a matter of convenience. Ask why it is proposed where it is.

Insulation on the ducting matters more in Canberra than in most of the country. A roof cavity here reaches extreme heat in summer and drops close to outdoor temperature on a frosty winter night, so conditioned air travelling through poorly insulated ducting loses a meaningful share of its heat before arriving. Ask what insulation rating the proposed ducting carries. It is one of the cheapest specification upgrades available at install time. Upgrading duct insulation afterwards means pulling the runs out and starting again. Almost nobody does it. Which is exactly why the specification matters at the outset.

Duct quality varies and the difference shows up over decades rather than immediately. Flexible ducting is the standard domestic product and perfectly serviceable when properly supported and not compressed, though it degrades over time and is vulnerable to rodents and to careless later trades working in the roof space. Support spacing is worth a question. Regular system servicing should include a look at accessible ductwork.

Return Air

Return air is the most neglected element of domestic ducted design and the most consequential. Every cubic metre of air the system pushes into your rooms must find its way back to the plant, an undersized return grille strangles the whole system regardless of how good the supply ducting is, and the symptom is poor performance that gets blamed on capacity. The air has to complete a circuit. Half a design that only considers the supply is not a design.

Grille position affects both performance and noise. A return placed in a central hallway draws air from the whole house effectively, one placed too close to the plant can be noisy, and a grille sized generously moves air at a lower velocity and therefore more quietly. Noise complaints frequently trace back to an undersized return. Nail down what size return is being provided and where it will go.

More than one return is worth considering in larger or divided homes. A single central return works well in a compact house with an open circulation path, whereas a sprawling layout, a house split across levels or one with doors habitually closed benefits from a second return serving the further zone. Two returns cost more to install. They usually cost less than living with a wing that never performs properly. Retrofitting a second return into a finished ceiling is the expensive alternative.

Closed doors are the practical enemy of return air in a bedroom. Air pushed into a room with the door shut has nowhere to go unless there is a gap under the door, a transfer grille or a dedicated return, which is why some rooms never reach temperature when the door is closed at night. That matters a great deal in a heating climate. Establish how the design handles bedrooms with doors closed overnight.

Filtration lives at the return and is worth planning for. The main filter sits behind the return air grille, its accessibility determines whether it will ever actually be cleaned, and a grille that is easy to open at a reachable height is the difference between a filter maintained every couple of months and one untouched for years. Establish where the filter sits and how it is accessed. Awkward access guarantees neglect.

Outlet Placement

Outlet placement deserves particular thought in Canberra because warm air and cool air behave in opposite ways. Cool air is dense and falls, so ceiling outlets distribute cooling beautifully, while warm air rises, which means heat delivered from ceiling outlets tends to sit at ceiling level unless it is thrown with enough velocity to reach the occupied zone. Most ducted design in this country assumes cooling is the priority. Here it is not.

This does not mean ceiling outlets are wrong in Canberra, since the overwhelming majority of ducted systems here use them successfully. It means the design has to account for the heating case deliberately: outlet type, throw pattern, velocity and position all determine whether warm air reaches the floor level where people actually are. Check how the proposed design handles heat distribution. It is a question that separates a designer from an order taker.

Room-by-room placement follows the same logic. Outlets positioned near external walls and windows counteract the cold surfaces that make a room uncomfortable, a single outlet in a large open plan area rarely distributes evenly, and rooms with high or raked ceilings need particular attention because the volume of air above head height is substantial. Window walls are worth targeting deliberately. Ceiling fans set to winter mode help push warm air back down.

Floor outlets appear in some Canberra homes and suit heating well where the construction allows. A raised floor with adequate subfloor clearance can take ducting beneath, delivering warm air at floor level where it rises naturally through the occupied space, though it is not an option on slab-on-ground construction which is common across much of the territory. Construction type decides whether it is even available. A ceiling fan installer offers a cheaper way to improve circulation in rooms with ceiling outlets.

Zoning Design

Zoning is the feature that renders a ducted system affordable to run rather than extravagant, and in a heating-dominated climate it earns its keep every winter evening. Motorised dampers open and close groups of outlets so the system conditions only the areas in use, which means heating a living area at night without also heating four empty bedrooms, and the saving across a Canberra winter is substantial. More zones deliver finer control. They also cost more to install. The additional cost is modest at installation and substantial afterwards. That asymmetry is worth remembering when the quote arrives.

Zone groupings should follow how the household actually lives rather than the floor plan. Living areas used in the evening, bedrooms used overnight, a home office used through the day and rarely used formal spaces are natural groupings, and lumping a home office in with bedrooms means running the whole sleeping wing to heat one room. Describe the daily routine to whoever is designing it. It changes the groupings more than the architecture does.

There is a technical limit on how few zones can run at once. A ducted system needs a minimum airflow to operate correctly, so closing too many zones starves the unit, which is why designs include a bypass, a constant zone or dump zone that stays open regardless. Ask how minimum airflow has been handled. A design that ignores it produces a system that struggles when only one zone is called.

Bypass arrangements differ and the distinction is worth understanding. A bypass duct returns excess air straight back to the plant when too many zones close, which protects the equipment but wastes the energy used conditioning that air, whereas a constant or dump zone directs the surplus into a real space such as a hallway so at least the heat goes somewhere useful. The second approach is generally preferable in a heating climate. Check which method the design uses. A dump zone into a hallway wastes considerably less than a plain bypass. The heat at least ends up inside the house.

Controllers vary from basic to sophisticated and the choice affects daily use. Simple controllers open and close zones on demand, better ones schedule by zone and day, and some offer individual temperature sensing per zone so each area holds its own setpoint rather than sharing one. Sensing per zone is worth considering in a house with varied orientation. Decide before installation, since retrofitting a controller upgrade later costs $800 to $2,500, and an after-hours electrician is an expensive way to discover a control fault in July.

Replacing Ducted Gas

Plenty of Canberra homes were built with ducted gas heating, frequently Brivis or Bonaire units, and are now weighing up reverse cycle, which raises an obvious question: can the existing ductwork be reused? Sometimes it can, but the assumption that it simply transfers across is where these projects go wrong, because gas ducted heating and reverse cycle move air in different ways. Gas heating delivers a smaller volume of much hotter air. The furnace raises the air temperature sharply and moves comparatively little of it. A heat pump does close to the opposite. Reverse cycle moves a larger volume of mildly warm air.

That difference has a direct consequence for duct sizing. Ductwork sized for the lower airflow of a gas furnace is frequently too small for the airflow a reverse cycle system needs, so reusing it produces exactly the throttled result described earlier, with reduced output, noise at the outlets and poor distribution to the far rooms. Have the existing ducting properly assessed rather than assumed adequate. An installer proposing to reuse it should explain why it is adequate.

Outlet positions carried over from a gas system deserve checking too. Gas ducted heating in older Canberra homes frequently used floor outlets, which suit heating well, and where a reverse cycle system is going into the ceiling instead the whole distribution pattern changes rather than merely the plant. Floor outlets cannot simply be capped and forgotten. Establish how the changed outlet arrangement was accounted for in the design. Old floor outlets usually need sealing properly rather than covering over.

Age and condition of the existing ducting matter alongside sizing. Ductwork installed decades ago may have degraded insulation, separated joints, crushed sections and rodent damage, and connecting new plant to tired ducting wastes much of what you have spent, which is why full or partial duct replacement often appears in these quotes at $3,000 to $8,000. Request its condition to be reported. Photographs from the roof space are reasonable to request.

The heating capacity calculation also changes with the technology. A reverse cycle system's heating output falls as the outdoor temperature drops, unlike a gas furnace whose output is constant regardless of the weather, so sizing on a straight swap from the old gas unit's rating will leave you short on the coldest Canberra mornings. Cold climate rated equipment addresses a good deal of this. Territory energy and sustainability information is published by the ACT environment directorate.

Decommissioning the gas side is part of the project and should be quoted. Removing or making safe the old furnace, dealing with the flue penetration in the roof, and any gas supply disconnection are separate trades from the air conditioning work, and leaving these as a loose end creates problems later. Find out what becomes of the old equipment. A hot water heat pump installer handles the related question of gas hot water if you are changing both.

What Drives the Price

Capacity and zone count set the base figure between them. Larger homes need more capacity and more zones, each zone brings a motorised damper, additional ducting and a share of the controller, and the step from five zones to eight is a real cost rather than a rounding difference. Settle the zone plan before comparing quotes. Two quotes with different zone counts are not comparable.

Staging the work is sometimes possible and worth asking about. Installing the plant and ducting with provision for zones to be added later, or completing the main living areas first with the capacity to extend, spreads the cost while avoiding the expense of retrofitting ducting into a finished house. Provision costs far less than retrofit. Decide what the house may eventually need rather than only what it needs now. Capped duct spurs left in the roof space cost very little at the time. Adding them later means going back into the ceiling.

Roof space conditions swing the labour substantially. A generous cavity with room to move and clear duct paths is straightforward, whereas a shallow pitch, awkward trusses, existing ductwork in the way or restricted access can add days to the job, and installers price that risk once they have been up there. That is why the roof space inspection matters. A quote given without it is guessing at the hardest variable.

Electrical supply work is the surprise that catches most households. A ducted system needs a dedicated circuit and appropriate protection, older Canberra switchboards frequently lack the capacity or the space, and that work sits at $600 to $2,000 before the air conditioning is connected. Ask whether the quote assumes an existing suitable supply. A switchboard specialist may need to attend before installation day.

Brand choice, warranty term and timing complete the picture. Daikin, Mitsubishi Electric, Fujitsu and Panasonic all supply ducted equipment into the Australian market, and ActronAir manufactures ducted systems in Australia, so there is genuine choice at most capacities. Warranty terms differ meaningfully between manufacturers and longer parts and labour cover is worth real money on a system at this price, quotes obtained during peak demand carry both a premium and a wait, and the shoulder seasons offer better pricing and immediate availability. Plan the project for autumn or early spring. Ducted installation during a July cold snap is the most expensive version of this job.

Capacity and Supply

Capacity should be calculated for the heating load in this climate, and that calculation is specific work rather than a rule of thumb. A proper assessment accounts for floor area and ceiling height, window area and orientation, insulation levels, external wall exposure, air leakage and how the household uses each space, then arrives at a capacity for the whole system and an airflow for each room. Floor area on its own is not a calculation. Put the question of what method was used and to see the result.

Undersizing shows up on exactly the days you needed the system. A unit that cannot meet the load on a minus four degree morning will run continuously without reaching temperature, cost more to operate than a correctly sized system, and leave the household reaching for supplementary heaters, which defeats the purpose of the investment. The coldest mornings are the real test. Design for those rather than for average conditions.

Oversizing carries its own penalties and they are less obvious. An oversized system reaches setpoint quickly then shuts down, cycling repeatedly rather than running steadily, which is less efficient, produces temperature swings and does less to manage humidity in cooling mode. Inverter systems tolerate moderate oversizing far better than older equipment. Deliberate oversizing still costs you at purchase and in operation.

Design conditions are worth asking about explicitly. Every capacity calculation assumes an outdoor temperature it is designed to cope with, a system designed to a mild assumption will disappoint on a Canberra minus four morning, and the figure used should reflect the actual local winter rather than a national default. Worth establishing what outdoor design temperature was assumed. It is a short question that reveals a great deal about the calculation behind the quote. An installer who has never been asked it will hesitate.

Building fabric belongs in the conversation before the capacity is fixed. Ceiling insulation, draught sealing and window treatments all reduce the load a system must meet, money spent there frequently outperforms money spent on additional capacity, and in older Canberra housing the gap between a sealed insulated house and a leaky one is considerable. Satisfy yourself whether fabric improvements would reduce the system size. A licensed electrical contractor can advise on the supply side alongside.

Ducted Costs Across Canberra

Ducted pricing across the Canberra districts tracks house size and roof space rather than suburb. Inner suburban stock brings older construction, variable roof access and switchboards that frequently need attention, Belconnen, Woden and Tuggeranong offer largely conventional single storey stock that suits ducted well, and Gungahlin and newer estates frequently have provision already allowed for. Roof access is the swing factor here. A local electrician handles supply works where the board needs upgrading first.

Two features recur across Canberra quotes. Homes built before insulation standards tightened often benefit more from ceiling insulation than from extra capacity, and any house with existing ducted gas heating needs the old ductwork properly assessed rather than assumed suitable for reverse cycle airflow.

Apartment and townhouse ducted installations bring their own constraints. Outdoor unit positions on balconies or common property need owners corporation approval, roof space may be shared or inaccessible, noise limits apply in most newer developments around the town centres, and the available plant positions are often dictated by the building rather than the design. Start the approvals early. They take longer than the installation itself.

Older Canberra homes carry one further consideration worth raising before anyone starts work. Houses built before the late 1980s can contain asbestos materials in eaves, ceiling linings and around service penetrations, ducted installation involves cutting ceiling openings and working in the roof space, and any suspicion of asbestos should be resolved by qualified assessment before work proceeds rather than during it. A competent installer raises this themselves. Where there is doubt, testing before the job starts is far cheaper than stopping midway.

Surrounding Districts

Travel and property type do most of the adjusting once you move past the suburbs. Canberra installers cover Queanbeyan, Jerrabomberra and Googong as a matter of course at close to city rates, properties scattered around Hall, Sutton, Murrumbateman and Bungendore pick up a travel component across a multi-day installation, and larger rural homes call for greater capacity and additional zones compared with a suburban house of similar age.

Rural homes around the territory present a different design problem from suburban ones. Larger floor areas, sprawling single storey layouts with long duct runs, higher ceilings and greater exposure all push capacity up, and the distance from the plant to the furthest rooms makes duct sizing and zoning more important rather than less. Long runs demand generous ducting. Skimping there produces rooms that never come up to temperature.

Sites at greater elevation face a colder design condition than the city does. Sites toward the ranges see harder frosts and lower overnight minimums, heat pump output falls further at those temperatures, and cold climate rated equipment moves from sensible to close to necessary. Design to the site rather than to the region. A repair specialist attending in winter will confirm which systems were sized properly.

Power supply is worth confirming early on rural blocks. Available supply capacity, existing switchboard condition and the length of the run from the meter all affect what can be connected, and discovering a limitation after the equipment is ordered is an expensive sequence. Raise supply capacity at the quoting stage. Installers experienced outside the suburbs will ask about it themselves.

What to Look Out For

Refuse a quote given without a roof space inspection. The cavity determines feasibility, labour and duct routing, none of which can be judged from the ground or from a floor plan, and a firm price offered without someone going up there is carrying assumptions you will pay for as variations. Ask what they actually saw in the roof space. The answer reveals whether they went up.

Look for a quote that specifies the ductwork rather than only the equipment. Duct sizes, insulation rating, outlet type and positions, return air size and location, and the zone plan should all appear, because those are the parts designed specifically for your house. A quote naming only the make and model has described the interchangeable half. That is where two very different jobs look identical on paper.

Be careful with proposals to reuse existing ducted gas ductwork without assessment. Ducting sized around a gas furnace rarely carries the airflow reverse cycle demands, reusing it undermines the entire investment, and the saving offered is small against the performance lost. Insist on the existing ducting to be inspected and reported on. Photographs are perfectly reasonable to request.

Confirm the licensing and what documentation you will receive. Refrigerant work and electrical work are separately licensed, commissioning results and a zone plan should be handed over at completion, and consumer guarantees apply to both the goods and the services regardless of what a warranty card says. Trade licensing in the territory is handled by Access Canberra. Consumer guidance is published by the Australian Competition and Consumer Commission.

Finally, be alert to a zone count chosen for the quote rather than for the house. Fewer zones make a quote cheaper and more competitive on paper while leaving you heating rooms you are not using for the next fifteen years, and the additional zone that costs $600 to $1,500 at installation is far more expensive to add later. Decide zoning on how the household lives. An electrical safety inspection is worth considering on older homes before adding this much load.

What to Look for in a Quote in the ACT

A ducted quote worth comparing describes the air distribution system rather than only the box. It should state the make, model and capacity of the indoor and outdoor units with heating and cooling outputs, confirm how the capacity was calculated and against which load, list the number and grouping of zones with the controller type, specify duct sizes and insulation rating, give outlet type and position for each room, state the return air size and location, set out exactly what electrical work is included, confirm the plant position and access, and name commissioning and documentation deliverables. Duct specification and return air sizing are what quotes most often omit. Their absence is the most useful signal a quote can give you.

Describe the property thoroughly when you enquire. Cover the age and construction of the house, single or two storey, approximate floor area and number of rooms to be conditioned, ceiling height and any raked ceilings, what you know about ceiling insulation, roof type and pitch, whether there is existing ducted gas heating or old ductwork in place, which way the living areas face, where an outdoor unit could go, and the approximate age of the switchboard. Note how the household uses the house through the day. That last point shapes the zoning more than the floor plan does.

Compare on the design rather than the figure at the foot of the page. Two quotes several thousand dollars apart routinely differ because one includes larger ducting, better insulation, an extra zone, a properly sized return and cold climate rated equipment while the other has trimmed each of those to reach a number, and the cheaper system will cost more to run for its whole life. Post it once here and several installers respond, which lets the designs be examined together. Where the prices diverge, ask each what duct sizes and return air they specified.

Settle the design, the electrical scope, the timeline and the documentation before committing. Confirm how capacity was calculated and to what design condition, agree the zone plan, establish which electrical work is priced in and what sits outside it, get the expected duration and disruption in writing, and confirm what you receive at handover. Then keep the whole set for as long as the system is in the house. The site also carries cleaning services for the clean-up afterwards, and one listing puts the job in front of licensed installers territory-wide. Building and planning requirements in the territory sit with the ACT planning authority.