Air duct cleaning is not something most Melbourne homeowners build into a regular schedule. When the booking is finally made, a common practical question is: how long will the technician actually be in my home? The answer depends on several factors — home size, system type, level of contamination, and whether additional services like mould remediation are required.
This guide gives you realistic time estimates by home size and system type, explains what factors can extend or shorten the service duration, and covers how to plan your booking day so the service runs smoothly.
Time by Home Size and Outlet Count
The primary driver of service duration is the number of supply and return air outlets in the home. More outlets means more duct runs to clean, more registers to remove and clean, and more sections requiring brush and compressed air treatment.
2–3 bedroom home (6–10 outlets)
A compact Melbourne terrace, apartment with ducted heating, or smaller house with 6 to 10 supply outlets typically takes 1.5 to 2.5 hours for a standard ducted gas heating clean. This covers the full 5-step process: inspection, negative pressure setup, rotary brushing, compressed air, and sanitisation. See our full guide on what to expect from a professional air duct clean.
3–4 bedroom home (10–15 outlets)
The most common Melbourne home size for ducted systems. A thorough clean of a 3 to 4 bedroom home takes 2 to 3 hours. This is the baseline estimate for most Melbourne suburban properties — Edwardian bungalows, 1970s brick veneer houses, and modern townhouses in this size range.
4–5 bedroom home or multi-zone system (15+ outlets)
Larger Melbourne homes — Federation-era houses, dual-storey properties, or homes with multiple zones — with 15 or more outlets typically take 3 to 4.5 hours. Multi-zone systems have additional duct branches and zone dampers that require individual attention.
Factors That Extend Service Duration
Several conditions can add 30 minutes to 2 hours to a standard duct clean. Understanding these helps set realistic expectations:
Systems never previously cleaned
A system that has never been professionally cleaned — common in Melbourne homes where the original ducted gas heating was installed 15 to 30 years ago — has significantly heavier debris accumulation. Additional brush passes and longer extraction time are required. Budget for an extra 30 to 60 minutes if the system has never been cleaned.
Mould contamination
Where mould is identified inside ductwork, the sanitisation step requires multiple fog passes rather than a single application. This adds 30 to 45 minutes to the total service time.
Pest activity or debris
Evidence of rodents or insects inside ductwork requires additional work to clear contamination from droppings and nesting material. The duct sections affected need extra mechanical cleaning and sanitisation. Add 45 to 90 minutes for significant pest contamination.
Post-renovation contamination
Homes where a recent renovation has deposited plasterboard dust, insulation fibres, or construction debris in the duct system require extended cleaning. Post-renovation duct cleans typically take 30 to 60 minutes longer than standard residential cleans.
Evaporative vs Ducted Heating Systems
The type of ducted system significantly affects service duration. Evaporative cooling systems require more components to be cleaned and serviced than ducted gas heating systems.
Ducted gas heating
A standard ducted gas heating system has a relatively simple duct network: supply registers, a main trunk line, and a furnace unit. Cleaning is primarily focused on the duct interior. This is the system type that fits the 2 to 3 hour estimate for a 3 to 4 bedroom Melbourne home.
Ducted reverse-cycle (heating and cooling)
Reverse-cycle systems are similar in duct complexity to gas heating but include an indoor fan coil unit that also requires cleaning. Add 20 to 40 minutes compared to a gas heating system for coil cleaning and condensate pan inspection.
Evaporative cooling systems
Evaporative systems have additional components: the roof-mounted unit (which includes a water distribution system, pads, and blower), the main duct plenum, and supply outlets. A thorough evaporative duct clean takes 30 to 60 minutes longer than an equivalent ducted heating clean. Melbourne homes with evaporative cooling should budget 3 to 5 hours for a full service.
Preparing for Your Booking Day
Proper preparation ensures the service proceeds without delays and reduces the chance of the technician needing to reschedule incomplete work:
Be home for the full service window
Book the service for a period when you can be home for the estimated duration plus 30 minutes buffer. If the technician finds unexpected contamination requiring additional work, you need to be available to discuss and approve any extra time or services.
Clear access before arrival
Move furniture covering floor registers and clear a path to the system unit. This is 10 minutes of preparation that prevents the technician having to wait on arrival. See our full guide to what to expect on the day for the complete preparation checklist.
Best time of year to book in Melbourne
February to April is the optimal booking window — before the May to August heating season peak, when scheduling is flexible and the system is fully accessible. April and May see the highest demand as Melbourne homeowners prepare for winter. Book early to secure preferred timing. See our guide on how often to clean air ducts in Melbourne for seasonal timing detail.