Cassette vs wall-split: which is right for your office?

If you've got a suspended ceiling, you have a choice between a four-way cassette and a wall-mounted split. Most offices end up specifying one or the other, often without understanding the real trade-off. Here's what an engineer would actually tell you.

Cassette: when it wins

• Suspended ceiling with at least 250mm void above
• Open-plan layout where 4-way airflow benefits everyone equally
• Aesthetic priority, the unit is flush with the ceiling, barely visible
• Larger rooms from about 30m² up

Wall-split: when it wins

• No suspended ceiling or insufficient void
• Cellular offices or smaller rooms under 25m²
• Budget priority, wall-splits are typically 20-30% cheaper installed
• Quick retrofit, minimal ceiling work means faster install

Install cost reality check

A typical 5kW cassette installed in a London office runs roughly £2,200–£3,000 supplied and fitted. The equivalent 5kW wall split runs £1,400–£2,000. The difference is the additional ceiling-mount labour, ducting, and the cassette unit itself being a more complex bit of kit.

Maintenance and life

Both have similar service intervals (annual F-Gas check, filter clean every 6 months). Cassettes are slightly harder to access for filter cleaning, you need a stepladder and to drop the grille. Wall splits you can wipe the filter in 30 seconds.

What we'd specify in your office

Open-plan, suspended ceiling, more than 25m²? Cassette. Anything else? Wall-split, almost always. If you'd like an engineer to look at your floorplan and give you a free recommendation, ring 0203 488 1889 or email a floorplan to info@becoolrefrigeration.co.uk.