Conservatories are one of the most frequently requested air conditioning installations we carry out — and also one of the most technically interesting. A well-designed conservatory air conditioning system genuinely transforms the usability of a room that many homeowners describe as unusable in summer and freezing in winter. But there are considerations specific to conservatories that affect the approach, the unit choice and the cost.
Why Conservatories Are Particularly Challenging to Cool
A conservatory is essentially a glass box. South and west-facing conservatories can reach 40°C+ in summer — the glass admits solar radiation but traps the resulting heat. The large surface area of single-glazed or even double-glazed glass loses heat rapidly in winter. The thermal mass is low — the room heats up and cools down quickly in response to external conditions.
All of this means a conservatory air conditioning system needs to work significantly harder than a comparable room with insulated walls. A conservatory of 20 sq metres may need the same cooling capacity as a living room twice its size in terms of effective heat load.
Sizing for a Conservatory
Standard room sizing rules do not apply directly to conservatories. We calculate heat load by taking into account glass area, orientation, type of glazing (single, double or triple) and shading. For a typical south-facing double-glazed conservatory of 15-20 sq metres, we typically recommend a 5kW unit — significantly more than the 2.5kW that might serve a comparable insulated room.
Getting the sizing right is particularly important in conservatories. An undersized unit will run at maximum capacity all day and still not reach target temperature on hot days.
Installation Challenges
Where to Mount the Indoor Unit
Most conservatories are built against the rear of the house, with a solid wall on one side. The preferred installation position is on this solid wall, where the unit can be fixed securely and pipework can pass through the wall to the exterior. Some conservatories are largely glass with only a narrow dwarf wall — mounting the unit on the dwarf wall is possible but requires careful structural assessment.
Where to Put the Outdoor Unit
The outdoor unit needs to go outside, which usually means the garden or a side passage. For conservatories at the rear of the house, the outdoor unit typically goes immediately outside the conservatory on a bracket or pad. Noise is a consideration — outdoor units are not silent and positioning them close to a neighbour’s boundary or bedroom window should be avoided.
Roof Type
Modern conservatory roofs — solid insulated roofs, Guardian roofs and similar — are significantly better thermally than traditional polycarbonate or glass roofs. A conservatory with a solid insulated roof may only need half the cooling capacity of the same conservatory with a polycarbonate roof. If you are planning both a roof replacement and air conditioning, it is worth doing the roof first as it will meaningfully reduce the cooling capacity required.
Best Units for Conservatories
Daikin Emura or Stylish: The wall-mounting options and attractive design suit a conservatory where aesthetics matter. The Emura in particular looks deliberate rather than functional.
Mitsubishi Electric MSZ-LN: Available in multiple colours to suit the conservatory interior. Very quiet — useful if the conservatory is used for relaxing or working.
Samsung WindFree Comfort 5kW: The WindFree technology distributes air without a direct draught — useful in a conservatory where you want cooling without sitting in a cold airstream.
Is It Worth It?
In our experience — yes, for conservatories that the homeowner actually wants to use. A conservatory that is too hot to use in summer and too cold in winter is effectively a corridor. Air conditioning transforms it into a genuinely usable room year-round. We regularly hear from clients that the conservatory has become their favourite room in the house following installation.
The cost — typically £1,500-2,200 for a standard conservatory installation — pays back in usability rather than financial return, but for a room that would otherwise be abandoned for 5 months of the year, it is a significant quality-of-life improvement.
Call 07833 053749 or request a free survey. We cover East Grinstead, Surrey, Sussex and South London.