Garden offices and garden rooms
Garden office air conditioning that heats it too.
One wall mounted unit warms the garden office on a January morning and cools it in July. Sized from the building, fully installed for one agreed price, from a base in Harrow and Stanmore.
- REFCOM certified REF1025662
- F-Gas Category 1 qualified
- Fully insured
Air conditioning installation across London. Based in Harrow and Stanmore.
2.5kW
Bedrooms and studies
From£1,995
Fully installed
3.5kW
Larger bedrooms
From£2,095
Fully installed
5.0kW
Living rooms
From£2,595
Fully installed
Starting prices, fully installed, including VAT. Which size your building needs is worked out at the free survey, not from this table.
One unit, both seasons.
Every unit we fit is a heat pump as well as an air conditioner. The same box on the wall that cools the building in summer reverses in winter and heats it, so the garden office needs nothing else.
It warms the room in minutes rather than the best part of an hour, because it blows heated air straight into the space. In a building you walk into at nine and leave at six, you heat it when you are in it, not all day on the off chance.
What a kWh of heat costs
- Electric panel, fan or oil filled heater
- 26.32p
- Daikin Comfora 2.5kW heat pump
- 5.7p
At the Ofgem price cap of 26.32p per kWh for 1 October to 31 December 2026. The heat pump figure uses Daikin's published seasonal efficiency (SCOP) of 4.61. Estimates, not quotes: what you pay depends on your tariff and how well the building holds heat.
Sized for winter, not just summer.
Most sizing advice is written for cooling. A garden office is usually the other way round, so the survey looks at three things before it picks a size.
The building, not the floor area
A garden building loses heat through its walls, its roof and a floor that sits over cold air, so in winter it can need more heat than its size suggests. We size garden offices on the heating load and then check the cooling fits, rather than the other way round.
Insulation and glazing
Heat leaves a thin walled building fast, and no unit keeps up with a shed. If the walls, floor and roof are insulated and the glazing is at least double, a heat pump has an easy job. If they are not, insulating first is the cheaper half of the problem, and we will say so.
Glass and which way it faces
A garden room with a wall of south facing glass gets very hot in a London summer. The glass and the direction it faces are part of the sizing, so the unit copes in July as well as in January.
Outside, power and drainage.
The parts of a garden office install that differ from a room in the house, and how each one is handled.
Where the outdoor unit goes
On the wall of the garden building on a bracket, or on feet on the ground beside it. Both are in the price. It goes where it has air around it, can be reached again, and is not pointed at a neighbour's window.
A short pipe run
With the outdoor unit beside the building, the pipework between the two is usually short. Up to 3m is in the price and anything past that is £45 per metre, quoted before you agree.
Where the water goes
The indoor unit makes water when it cools and the outdoor unit makes water when it defrosts in heating. Both need somewhere to drain, which we plan so it does not end up on a path that freezes.
The power supply
The unit needs its own electrical supply, and the cable out to the garden has to be big enough for the unit and everything else out there. A complete new circuit is notifiable work under Part P in England. We check what is already there at the survey, and anything the supply needs is in the written quote before you agree.
Planning, in brief.
The short version of the permitted development rules as they apply to a garden building in England. Our planning guide has them in full.
Does a garden office unit need planning permission?
Usually not. The permitted development rules for air source heat pumps cover one fitted on a building in the garden of a house, with the same limits as one on the house: the outdoor unit no bigger than 1.5 cubic metres, not on a pitched roof, at least a metre in from the edge of a flat roof, and installed to the MCS planning standard.
What if the house already has a unit?
The count covers the house and the garden together. A detached house can have two outdoor units as permitted development, any other house one. So if a semi or a terrace already has one on the house, the garden office unit needs planning permission.
Does it matter that it is air conditioning?
Only if it cools and nothing else. The rules cover a heat pump that is not used solely for cooling. Every unit we fit heats as well as cools, which is what keeps a standard install inside them.
Listed buildings and flats?
Permitted development does not apply within the grounds of a listed building, and the rules above are for houses. If either applies to you, tell us when you call. This is not legal advice, and your council is the only body that can give a binding answer.
What the price includes
- Up to 3m of pipework
- External trunking, the cover that hides the pipework outside
- Bracket or feet for the outdoor unit
- A gravity drain, so the water runs away without a pump
- Electrical connection by a qualified electrician
- A fused spur on 2.5 and 3.5kW, or its own circuit from your fuse board on 5.0kW and up
- Commissioning, and a handover pack you keep
The prices shown are starting prices for a standard installation. If your job needs longer pipe runs, a condensate pump, access above the first floor, or work on your consumer unit, we price it in your quote, never on the day.
Optional extras
Priced in your quote before you agree, so nothing is added on the day.
| Extra | Price |
|---|---|
| Pipework beyond 3m | £45 per metre |
| Internal boxed trunking | £35 per metre |
| Condensate pump | £160 |
| Removal of an old system | £250 |
| Two visit installation | Plus 10 percent |
Price it now
Size the room in 60 seconds for a starting price, or call or WhatsApp and describe it. The exact number is agreed at the free survey, before any work is booked.
Questions we get asked.
Can I leave it on overnight in winter?
Yes, and it is worth doing. A garden building allowed to go fully cold can get condensation on cold surfaces when it is warmed up again. Holding a low background temperature is cheap with a heat pump and kinder to the building and anything electronic left inside it.
Will it cope with a cold snap?
Daikin publishes heating output down to minus ten degrees outside. Its 2.5kW Comfora still delivers 2.09kW of heat at that temperature, far colder than a normal London winter night.
Can I warm it up from the house?
On most of what we fit, yes. The Daikin Comfora runs from Daikin's Onecta app, both Samsungs have Wi-Fi built in, and the MHI ZS we fit has wireless LAN built in, so the building can be warming up before you walk out to it.
Is a garden office different to price?
The unit and the standard installation are priced exactly as in a house. What can differ is the power supply to the garden and the pipe run, and both are checked at the free survey and written into the quote before anything is booked.
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Instant estimate
Want a price for the garden office?
Tell us the size of the building and get a starting price in about a minute. The supply, the outdoor unit position and the pipe run are checked at the free survey.