At a Glance
Ventilation and exhaust fan installation in Melbourne typically costs $200–$1,450 per job. A straightforward bathroom fan replacement with existing ducting and wiring sits at the low end. New installations through double-brick walls, multi-room extraction, or roof ventilation upgrades push toward the top.
What's Included in the Price
- Supply and install of the exhaust fan (ceiling-mounted, wall-mounted, or inline)
- Ducting from the fan to an external discharge point (roof cowl or wall vent)
- Electrical connection or switch wiring, compliant with AS/NZS 3000 Wiring Rules
- Roof or wall penetration with weatherproof sealing
- Extraction capacity sized to meet AS 1668.2 Ventilation Design minimums
- Testing and commissioning
Materials typically account for 20–30% of the cost. Labour and access difficulty drive the rest, especially in Melbourne's older housing stock where double-brick walls and tight roof spaces are common.
What Affects the Cost
- Wall construction. Double-brick walls, which are the norm across Melbourne's inner and middle suburbs, require core drilling for any external wall penetration. This is slower and more expensive than cutting through timber frame. The cavity between brick layers also needs proper sealing to prevent drafts and water ingress.
- Fans venting into the roof cavity. Many Melbourne homes built before the mid-1990s have bathroom fans that exhaust into the roof space rather than outside. In Melbourne's cold, damp winters, this causes severe condensation on the underside of roof tiles and on timber framing. Correcting this by adding ducting to an external point is one of the most common — and most valuable — ventilation jobs.
- Ducting condition and length. Replacing a fan using existing, well-routed ducting is quick. Running new ducting through a roof space with low clearance, around obstacles, and with multiple bends takes much longer. Old flexible foil ducting that has sagged or kinked should be replaced with rigid or semi-rigid duct.
- Number of fans and rooms. A single bathroom is straightforward. Adding extraction to a second bathroom, ensuite, and laundry multiplies duct runs and penetration points.
- Roof access. Many period homes in Melbourne have low-pitch roofs with limited crawl space. Cathedral ceilings in renovated homes eliminate roof space entirely, requiring alternative ducting routes.
- Electrical work. A new fan on an existing circuit with a nearby switch is simple. Running a new circuit from the switchboard, adding a timer switch, or wiring a humidity sensor adds to the electrical scope.
- Roof ventilation. Replacing passive whirlybirds with powered roof ventilation (solar or mains) involves larger penetrations and more robust mounting.
A simple like-for-like bathroom fan swap with working ducting sits toward $200. Installing exhaust fans in multiple rooms with new ducting, core-drilled wall vents through double brick, and new switched circuits in a period home with limited roof access pushes toward $1,450.
Melbourne-Specific Considerations
Melbourne's climate makes proper ventilation more important than in most Australian cities. Cold winters create extreme condensation: a hot shower in a 5°C ambient temperature produces far more moisture than the same shower in Brisbane's 20°C winters. Without effective extraction, that moisture sits on walls, ceilings, windows, and inside roof cavities, feeding mould growth that is very difficult to eliminate once established.
The inner suburbs — Fitzroy, Carlton, Brunswick, Richmond, Northcote — are dominated by Victorian-era homes and Edwardian cottages. Many of these have had bathrooms added or upgraded over the decades, but the exhaust fan installation was often an afterthought. Fans venting into the roof cavity are extremely common, and the resulting moisture damage is a recurring issue at building inspections. If you own one of these homes and your bathroom fan does not have visible ducting running to a roof cowl or external wall vent, it is almost certainly dumping moisture into the ceiling space.
Double-brick construction, standard across much of Melbourne from the 1920s through the 1970s, means any new external wall vent requires core drilling through two layers of brick. This is not a DIY job and adds both time and cost compared to timber-frame construction. The cavity between brick layers must also be properly sealed to prevent moisture and drafts entering the wall space.
For kitchen ventilation, Melbourne's terrace renovations and period home extensions frequently feature open-plan kitchen-living areas. Ducting a rangehood externally through a brick wall or up through the roof adds complexity. If you have a gas cooktop, the National Construction Code requires external ducting — a recirculating rangehood does not meet the requirement.
Roof ventilation is also worth considering in Melbourne. Dark-coloured roofs on period homes absorb significant heat in summer, making upper floors uncomfortably hot. Powered roof vents (solar or mains) are far more effective than passive whirlybirds, which rely on wind and do very little on still days.
Hiring a Licensed Air Conditioning Technician in VIC
In Victoria, all hardwired electrical work must be performed by a licensed electrician registered with Energy Safe Victoria. The electrician must issue a Certificate of Electrical Safety on completion, which is your proof the work meets Australian Standards.
Ventilation work in Melbourne typically involves an electrician for wiring and a ventilation specialist or air conditioning technician for ducting design and installation. Many installers hold both qualifications. If separate tradespeople are involved, confirm who is responsible for the overall system performance — the ducting is only effective if the fan is correctly sized and the electrical connection is reliable.
Ask for the Certificate of Electrical Safety before making final payment. You can verify a Victorian electrical licence on the Energy Safe Victoria website.
How We Calculate
Estimates are based on surveyed trade rates for licensed electricians and air conditioning technicians in the Melbourne metro area, adjusted for property age. All prices include GST. Figures cover standard residential exhaust fan and ventilation work. Commercial extraction systems and ducted air conditioning are not included.