Domestic vs Commercial Air Conditioning: The Real Differences

Equipment you tend to see in each

In homes, wall-mounted split units are by far the most common choice. They are compact, reasonably priced to fit and simple to control from a remote or phone app. Multi-split systems, where one outdoor unit serves several rooms, suit houses where outside space is tight. Ducted systems appear in higher end renovations where the owner wants nothing visible in the room.

In commercial buildings, ceiling cassettes are the workhorse because they sit flush in a suspended ceiling and throw air in four directions across an open space. Larger offices may use VRF systems with many indoor units on shared pipework, and comms rooms need dedicated units built for continuous duty.

Sizing: rooms versus loads

A domestic system is usually sized room by room, looking at floor area, glazing, which way the room faces and how well it is insulated. A bedroom and a south facing conservatory of the same size can need quite different capacities.

Commercial sizing has to add the internal gains. Every person, screen, fridge, oven and light fitting puts heat into the space, and in a busy shop or kitchen those gains can outweigh the heat coming through the walls. Undersized commercial equipment runs flat out all afternoon and still loses the battle, which is why a proper heat load assessment matters more in business premises.

Running hours and wear

More hours means more wear on fans, filters and compressors, so the service interval for a busy commercial system is usually shorter than for a house.

• Homes: typically evenings, nights and warm weekends, often only for part of the year
• Offices: working hours on weekdays, sometimes with heating mode used in cooler months
• Retail and hospitality: long trading days, with doors opening constantly
• Server and comms rooms: every hour of every day, all year round

Maintenance and legal duties

Anyone handling refrigerant must be F-Gas certified, whether the job is in a flat or a factory. Beyond that, businesses carry extra responsibilities as the operator of the equipment: larger systems need periodic leak checks and records under the F-Gas rules, and employers have a general duty to keep workplace temperatures reasonable.

For that reason most commercial clients put their systems on a maintenance contract with planned visits, leak checks and written reports. Homeowners are more likely to book a periodic service when they need one, although a regular clean still keeps a domestic unit efficient and quiet.

Mixed use buildings

Plenty of properties sit in between: a flat above a shop, a garden room used as an office, a small clinic in a converted house. In these cases we specify each area for how it is really used rather than forcing the whole building into one category, so a treatment room might get commercial style sizing while the living space upstairs keeps quiet domestic units.

How we approach either job

Every installation starts with a free site survey, followed by a written quote with no hidden costs. We work across Hertfordshire, Buckinghamshire, Bedfordshire and London from our base in Hemel Hempstead, and every system we fit can heat as well as cool. If you are not sure which route suits your building, describe how the space is used when you call and we will tell you honestly.