What's Included
A typical ventilation or exhaust fan installation covers:
- Supply and install of the fan unit (ceiling-mounted, wall-mounted, or inline)
- Ducting from the fan to the external discharge point (roof cowl or wall vent)
- Electrical connection to an existing circuit or dedicated switch, compliant with AS/NZS 3000:2018 Wiring Rules
- Roof or wall penetration and weatherproof sealing at the discharge point
- Extraction rates sized to meet AS 1668.2 minimums (25 L/s for bathrooms, 50 L/s for kitchens)
- Testing and commissioning to confirm airflow at the discharge point
The fan unit itself is usually 20–30% of the total cost. Labour, ducting materials, and the roof or wall penetration make up the rest, and this is where prices vary most between homes. A basic ceiling-mounted exhaust fan costs $50–$120 as a unit, while an inline fan with ducting components runs $200–$400. The labour to install, duct, and wire a single fan typically takes 2–4 hours.
Ventilation Types and What They Cost
The right ventilation approach depends on what problem you are solving: bathroom moisture, kitchen fumes, roof heat, or subfloor dampness. Each has different equipment, installation complexity, and cost.
Bathroom Exhaust Fans
| Fan Type | Unit Cost | Installed Cost | Best For |
|---|---|---|---|
| Basic ceiling-mounted (e.g. Clipsal Airflow CE250) | $50–$120 | $200–$450 | Simple replacement with existing ducting |
| Ceiling fan with LED light | $80–$180 | $250–$500 | Combined lighting and extraction |
| 3-in-1 heater/fan/light (e.g. IXL Tastic Vivid) | $185–$550 | $400–$900 | Bathrooms needing heat, light, and extraction in one unit |
| Premium 3-in-1 (e.g. IXL Tastic Luminate) | $700–$1,000 | $900–$1,400 | Design-conscious bathrooms, higher extraction rates |
| Inline fan, roof-space mounted (e.g. Fantech Rapid Response) | $170–$290 | $400–$700 | Quieter operation, longer duct runs, multi-room extraction |
Inline fans sit in the roof space rather than in the ceiling, connected to the room by a duct and a grille. The motor noise stays in the roof cavity, making them noticeably quieter. A single inline fan can serve two rooms via a Y-junction, which reduces the number of roof penetrations needed.
Kitchen Rangehood Ducting
A ducted rangehood pushes cooking fumes, grease, and moisture through ductwork to the outside. A recirculating rangehood filters and recirculates air back into the kitchen. Ducted rangehoods are far more effective, and the National Construction Code requires external ducting for gas cooktops.
Installation costs for ducted rangehood venting (ductwork only, not the rangehood itself) run $300–$1,000 depending on duct length and whether the exit is through a wall or roof. Schweigen silent rangehoods use a remote motor in the roof space connected by ducting, keeping kitchen noise below 40 dB. Schweigen units start at around $1,200 for the rangehood, with installation adding $400–$800.
Roof Ventilation
| System Type | Unit Cost | Installed Cost | Performance |
|---|---|---|---|
| Whirlybird (turbine vent, e.g. Edmonds WindMaster) | $80–$150 | $250–$500 | Wind-dependent, moves 100–200 m3/hr in moderate wind |
| Solar-powered roof ventilator (e.g. Solar Whiz) | $400–$700 | $700–$1,000 | Moves 700–2,100 m3/hr, operates in direct sun regardless of wind |
| Mains-powered roof ventilator | $300–$500 | $600–$900 | Consistent output regardless of conditions, requires electrician |
Whirlybirds are cheap but wind-dependent. On still, hot days when you need ventilation most, they do very little. Solar-powered units like the Solar Whiz range operate at peak output during peak heat, moving 10–15 times more air than a whirlybird. If you are paying for installation labour anyway, a powered option gives significantly better results.
Subfloor Ventilation
Raised-floor homes, particularly older weatherboard houses and Queenslanders, can develop damp, musty conditions underneath when natural airflow is blocked by landscaping, enclosed stumps, or added skirtings. Subfloor ventilation fans restore air movement and reduce moisture that feeds mould and attracts termites.
Systems like Envirofan use low-voltage fans (12V) that can run on solar, costing around $4 per year in electricity. A dual-fan system extracting 3,250 L/min costs $200–$400 for the kit. A quad-fan system (6,500 L/min) runs $350–$600. Professional installation, including fan positioning, wiring, and vent modification, adds $300–$800 depending on access and the number of fans.
Heat Recovery Ventilation (HRV)
Whole-house HRV and energy recovery ventilation (ERV) systems are common in Europe and gaining traction in Australian new builds, particularly in climate zones 6–8 (Melbourne, Hobart, highland areas) where homes are built to higher airtightness standards under NCC 2022. These systems exchange stale indoor air for fresh outdoor air while recovering 70–90% of the heat energy. Single-room decentralised HRV units from brands like LUNOS and Stiebel Eltron start at $400–$1,500 per unit installed. Whole-house ducted systems run $3,000–$8,000 installed.
Signs Your Home Needs Better Ventilation
Not every ventilation problem is obvious. Some indicators to watch for:
- Persistent condensation on windows, particularly in winter mornings. This means moisture-laden air is not being extracted.
- Mould on bathroom ceilings or walls that returns within weeks of cleaning. The underlying moisture source has not been addressed.
- Musty smell in the house, especially noticeable when returning after time away. Often indicates subfloor dampness or poor air circulation.
- Peeling or bubbling paint in bathrooms, laundries, or ceilings. Moisture trapped behind the paint film is breaking the bond.
- Visible condensation in the roof space, particularly on the underside of roof tiles or sarking. A strong sign that a bathroom fan is venting into the cavity rather than outside.
- Foggy bathroom mirrors that take a long time to clear after showering. A properly sized and ducted exhaust fan should clear visible moisture within 10–15 minutes.
The NCC 2022 condensation management provisions (Part F8 for commercial buildings, Part 10.8 for housing) now specifically require builders to address condensation risk in new homes. For existing homes, retrofitting proper ventilation is the most practical way to manage the same risks.
What Affects the Cost
- Fan type and capacity. A basic $60 ceiling-mounted bathroom fan is inexpensive to buy and install. An IXL Tastic 3-in-1 at $550 or a Fantech inline fan at $290 costs more upfront but delivers better performance and features. High-capacity kitchen extraction fans are larger and more expensive again.
- Number of rooms or fans. A single bathroom fan is straightforward. Adding extraction to two bathrooms, a laundry, and a kitchen multiplies ducting runs and penetration points.
- Ducting requirements. If ducting already exists and is in good condition, the job is much simpler. New ducting runs through roof spaces, especially long or complex routes with bends, add significant cost. Rigid or semi-rigid ducting ($15–$25/m) costs more than flexible foil ($8–$12/m) but performs far better and lasts longer. Old flexible foil ducting that has sagged or kinked should be replaced.
- Roof access. Easy roof access with plenty of clearance keeps labour time down. Tight roof spaces, cathedral ceilings, or flat roofs make ducting installation harder and slower.
- Wall or roof penetration. Every new external discharge point requires cutting through the roof or wall, installing a cowl or vent ($30–$80), and sealing against weather. Brick and concrete walls need core drilling ($150–$250). Tile roofs require careful work to avoid cracking surrounding tiles.
- Power source. All hardwired fans need a licensed electrician. If no existing circuit reaches the fan location, running new cable adds cost. Fans with timers or humidity sensors require additional wiring.
- Bathroom fans venting into the roof cavity. Many older Australian homes have exhaust fans that dump moist air into the roof space rather than outside. Correcting this means adding ducting and a discharge point, which costs more than a simple fan swap but prevents serious mould and timber damage.
A straightforward swap of a single bathroom ceiling fan where ducting and wiring already exist sits toward $200. Installing extraction fans in multiple rooms with new ducting runs through a tight roof space, external wall penetrations through brick, and new electrical circuits pushes toward $1,500.
City and Regional Price Comparison
At the city level, Sydney is the baseline at $200–$1,500 per job. Melbourne pricing tracks close to Sydney, though double-brick walls in older suburbs make external wall penetrations more involved. Brisbane often benefits from lighter timber-frame construction and accessible raised-floor homes, though the subtropical humidity makes proper ventilation more critical than in any other capital.
Perth and Adelaide typically run 10–15% higher on labour due to smaller trade pools. Perth's dry climate means ventilation work is less frequent, which can mean fewer specialists and slightly longer lead times. Adelaide's older stone cottages present thick wall penetration challenges similar to Melbourne's double brick.
Within any city, the biggest price variation comes from construction type and roof access. A 2010-era project home with a tile roof, timber frame walls, and generous roof clearance is a half-day job. A 1930s brick bungalow with a low-pitch iron roof, double-brick walls, and fans currently venting into the ceiling space is a full day or more.
How We Calculate
Estimates are based on surveyed trade rates for licensed air conditioning technicians and electricians, adjusted for each state and property age. All prices include GST. Figures cover standard residential ventilation and exhaust fan work. For whole-house heating and cooling, see our ducted air conditioning guide. Commercial extraction systems and whole-house ventilation systems are not included.