Division 40 · whole house

Ducted air conditioning: effective life and depreciation rate

The Commissioner's table gives a packaged unit 15 years, a condensing set 15 and the fan coil unit connected to it 15, and a zone's damper motor 10: each is plant. The ducts, vents and pipes in the ceiling are capital works at 2.5%. The price on this page is for a whole house's system supplied and installed, ductwork included, and so are the five years worked from it: a schedule takes the ductwork out to capital works, and no price we hold says what share of the system it is.

Effective life: 15 yrs
DV · PC rate: 13.33% · 6.67%
Installed new, 2026: $12,139

A room the ducts do not reach may have a window or wall air conditioner of its own: a separate asset, plant with a 10-year life, not part of the ducted system.

Five years of ducted air conditioning bought new

Ducted air conditioning costing $12,139, held for each full year, under each method. These figures take the whole system's price as one asset at the packaged unit's 15-year life, so they include the ductwork, which is capital works at 2.5% a year, not plant: over these five years they deduct more on its share than capital works would. No price we hold gives its share, so this page cannot work it apart. The $12,139 is for a whole house's ducted system, and whether that is one asset or each unit in it is its own is a question of fact and degree (section 40-30). As one asset it is above the $1,000 low-cost threshold and is deducted at its own rate, as the table works it: under diminishing value its written-down value is $924 after 18 full years, past the end of its 15-year life, under $1,000, so from year 19 it can go into the low-value pool. A unit in it that is its own asset is tested on its own cost: under $1,000, it can be pooled from the start, and at $300 or less it is written off in the year it is installed unless it is part of a set, or one of identical items, costing more than $300 together (section 40-80(2)).

Deductions for ducted air conditioning over five years under each method
Year	Diminishing value 13.33%	Prime cost 6.67%
1	$1,619	$809
2	$1,403	$809
3	$1,216	$809
4	$1,053	$809
5	$913	$809
Five years	$6,204	$4,045

Full years of 365 days. Diminishing value and prime cost are worked by days held ÷ 365 (sections 40-72 and 40-75), so a year that includes 29 February, held throughout, claims 366/365 of what a 365-day year would on the same value. The first year is pro-rated by the days the item is held for earning rent, except in the pool, whose rates are not by the day.

What ducted air conditioning cost installed, by year

2000$7,470
2010$8,993
2020$10,150
2026$12,139

The effective life of ducted air conditioning fitted new in a property built in 2011 ends in 2026, while the building's own capital works deduction runs to the 2050–51 income year: see depreciation on a property built in 2011.

Price is for a whole house's ducted system.

By dwelling type

Our dwelling pages price ducted air conditioning with the typical plant of a townhouse and an apartment in every state; two states of each:

Each is priced at its state's rates, and the state's own page sets the four types side by side: Victoria, South Australia and the Northern Territory.

Common questions

What is the effective life of ducted air conditioning?

15 years, as the Commissioner of Taxation determines it for "Packaged air conditioning units" under "Air conditioning assets (excluding ducting, pipes and vents)" in the residential property operators' table of the Income Tax Assessment (Effective Life of Depreciating Assets) Determination 2025, which most schedules use (an owner may estimate its own instead, section 40-105). Seven of the other 36 items here share it, among them a floating timber floor and an evaporative cooler.

What is the depreciation rate for ducted air conditioning?

13.33% a year under diminishing value (200% ÷ 15), taken from what is left of the value: $1,619 of the $12,139 it costs installed new in the first full year, $913 in the fifth. Or 6.67% a year under prime cost (100% ÷ 15), taken from the cost: $809 in each of the first five. Both take the whole system's price at the packaged unit's life, so they include the ductwork. An item first held before 10 May 2006 takes 150% ÷ 15 under diminishing value.

Can I claim ducted air conditioning that came with the property?

Generally not, for an individual, a self-managed super fund or most trusts and partnerships that bought an established property at or after 7.30 pm on 9 May 2017 (section 40-27; the 2017 rules set out who it reaches and the exceptions). Such plant is still valued, at what it costs new in the year the property is bought less its age and condition: for ducted air conditioning 8 years old in good condition, about $5,665 of the $12,139 new in 2026, a value whose decline can make a capital gain or loss when it is sold or scrapped. That value is worked on the whole system's price at the packaged unit's life, and so includes the ductwork, which is capital works, outside section 40-27. For ducted air conditioning bought new for the property while it is let, and never used while it was the owner's home, deductions start on the day of installation.

What does it cost to install ducted air conditioning?

About $12,139 installed new in 2026, from our cost database (a whole house's ducted system), and about $8,993 in 2010. The other items here nearest it in price are a floating timber floor (about $10,824, with a 15-year life) and a solar power system (about $4,899, with a 20-year life).

Other items

Air conditioning assets (excluding ducting, pipes and vents) in the Commissioner's table

General information only, not advice about your circumstances. Speak to a registered tax agent before relying on it.