How much does ducted air conditioning cost?
By Airva Editorial Team · Checked against published UK guidance · Updated
On our numbers, the ducted part of ducted air conditioning adds £1,500 to £4,000 to what the same job would cost with a wall-mounted unit. That premium pays for the ductwork, the grilles and the labour of getting them into a ceiling or loft. Everything else in the price, the condenser, the refrigerant pipework, the electrics, the commissioning, costs much what it would for any split system. So a straightforward job with one concealed indoor unit and one outdoor unit comes out at roughly £4,000–£9,100 in our estimator. For a whole house, our own ballpark starts around £8,000.
How our estimate is put together
Our cost estimator adds a handful of components together, each with a low and a high figure. None of it is a quotation; it is the arithmetic we use to tell a plausible quote from an implausible one.
| Component | Our low–high | What it stands for |
|---|---|---|
| Base equipment and installation | £1,500–£3,000 | The fixed cost of any job, before anything specific to your house |
| Each indoor unit | £400–£900 | For ducted, each concealed unit, not each grille |
| Each outdoor unit | £600–£1,200 | Usually one for a ducted system |
| Ducted premium | £1,500–£4,000 | Ductwork, plenum, grilles, and the labour in the void |
| Moderate complexity | £400–£1,000 | Longer runs, awkward access, a condensate pump |
| Complex | £1,200–£3,000 | Builder's work, difficult voids, multiple floors |
| Concealed pipework | £300–£1,200 | Refrigerant pipes chased into walls rather than run in trunking |
Two things follow. A ducted system serving four rooms from one concealed unit is priced on one indoor unit, which is why ducted economics improve the more rooms each unit serves. And the ducted premium is the widest single line in the table, because "put a duct in the ceiling" covers anything from an open loft to a void you can barely get an arm into.
Three houses, three bands
| The job | How we enter it | Our estimate |
|---|---|---|
| Loft conversion, one concealed unit in the eaves void serving the new room | 1 indoor, 1 outdoor, standard | £4,000–£9,100 |
| Three bedrooms under an open loft, one unit with longer duct runs | 1 indoor, 1 outdoor, moderate | £4,400–£10,100 |
| Two-storey retrofit, a unit in the loft and another in a first-floor ceiling void | 2 indoor, 1 outdoor, complex, concealed pipework | £5,900–£14,200 |
For comparison, the same three bedrooms done with a multi-split, three wall units on one condenser with pipes in trunking, comes out at £3,600–£7,700 on the same rules. Ducted at moderate complexity against the multi-split at standard complexity, concealment adds £800 to £2,400 in that house.
What moves a ducted job up the band
Getting into the void
The first thing an installer prices is access. A boarded loft with a proper hatch and headroom is a different day's work from a shallow void reached through a hatch in a cupboard ceiling. Insulation has to be lifted and put back, a platform built for the unit, and a route kept clear for whoever changes the filters in five years. If the unit needs a void deeper than the house has, a boxed bulkhead gets built, and that is builder's work at builder's rates.
The duct runs
Every extra metre, bend and floor crossed adds labour, and long runs need an indoor unit with enough fan pressure to push air to the furthest grille. That usually means a higher-specification unit than a short run would need. Ducts through a cold loft must be insulated so they do not drip condensation onto the ceiling below, and where a duct passes through a fire-separating floor, which in a loft conversion it often does, the fire-stopping is part of the job, not an afterthought.
Grilles and zones
Each room needs at least a supply grille, and the system needs a return path. An unzoned system is cheaper and gives every room broadly the same air. Zoning adds a motorised damper and a controller for each zone, so it costs more per room, but it is the specification most homes need; our ducted systems guide explains why one temperature for the whole floor rarely works.
Making good
Grilles mean holes in ceilings, and in a retrofit a duct route sometimes means opening a ceiling and closing it again. Ask every installer the same question: who does the plastering and decorating afterwards? Many air conditioning firms do not, and a quote that stops at "cut and fit grilles" leaves you finding a plasterer. That is the most common reason two ducted quotes look further apart than they are.
The indoor unit and controls
A unit in a loft usually cannot drain by gravity to a convenient point, so a condensate pump goes in, along with a safety tray and an overflow route, because a leak there comes through a ceiling. Controls range from one wired controller to a panel per zone with app control.
Where the premium buys something
You are not paying extra for better cooling. A ducted system and a multi-split of the same capacity cool a room equally well. What the premium buys is nothing on the walls and air spread through a room from several grilles rather than one unit.
That is worth paying for when there are four or more rooms on a floor with a usable loft above them, when wall units are unacceptable in the rooms concerned, or when an open-plan space needs air from more than one point. It is rarely worth it for two rooms, or in a house with no void, where builder's work can overtake the air conditioning. If the comparison is close, the whole-house guide sets the options side by side.
Do it while the ceilings are down
The cheapest ducted system is the one installed during building work you were doing anyway. With ceilings open or not yet boarded, duct runs go in at first fix, there is nothing to make good, and pipes can be buried in walls before plastering for little extra.
On our rules, the two-storey retrofit above costs £5,900–£14,200. The same two units installed as a standard job, without the complexity or concealment lines, come to £4,400–£10,000. Not all of that £1,500–£4,200 difference disappears in a real renovation, but most of what it stands for does. A loft conversion is the clearest case: the eaves void is created by the work itself and the room is usually the hottest in the house. A new build is better still, if you can get the duct design onto the drawings before the joists are ordered.
Ducted heat pump installation cost
A ducted system that heats as well as cools is a ducted air-to-air heat pump: the same equipment, run in reverse in winter. You want a reversible unit in any case, because the permitted development right for an outdoor unit does not cover equipment used solely for cooling [1].
The heating side raises the grant question. The Boiler Upgrade Scheme offers £2,500 towards an air-to-air heat pump [2], but only in a residential property and only if the home is not left with any fossil fuel heating [3]. The installer and the product must both be MCS certified [4], so ask the installer to confirm that the specific unit is listed on the MCS product directory before you count the grant. Our grant eligibility checker works through the conditions, and air-to-air heat pump costs covers the heating comparison.
After installation
Servicing a ducted system costs more than servicing a wall unit, typically £150–£250 a visit on our estimates, because the ducts and grilles are inspected as well as the plant. The cheapest way to keep that bill down is decided at installation: an access hatch you can reach and a unit positioned so its filters come out without an engineer lying across the joists. See air conditioning service costs.
Put your own house through the numbers
Choose ducted in the cost estimator, enter the number of concealed units and how awkward the void is, and you will get the band we would use to judge a quote. If you are still deciding between ducted and wall units, the ducted systems guide covers what a house needs before a concealed system is realistic.
Sources
Every price on this page is Airva's own planning estimate, worked from the rules our cost estimator uses. They are not quotations and no third party stands behind them; the firm number comes from a survey. Published rules and figures are cited below.