The two main HVAC technologies in London commercial offices. Different energy profiles, different comfort, different maintenance needs. This guide compares them across the factors that matter.
Variable Refrigerant Flow systems — one outdoor condensing unit linked to multiple indoor fan-coil units via refrigerant pipework. Flexible zoning, individual control.
Water-based cooling — chilled water circulates through ceiling-mounted 'beams' that cool passing air. Active beams combine cooling with fresh-air supply; passive beams rely on natural convection.
| Factor | VRF | Chilled beams |
|---|---|---|
| Energy efficiency | COP 3–4 | COP 5–7 |
| Installation cost | £120–£200/sqm | £180–£280/sqm |
| Ceiling height required | 2.5m+ | 2.8m+ |
| Comfort | Good; fan noise | Silent; occasional draught |
| Individual control | Room-level | Zone-level |
| Maintenance | Filter/coils F-Gas | Water treatment, coil cleaning |
| Best for | Flexible, smaller plates | Large plates, low-noise critical |
M&E alterations for both VRF and chilled-beam systems. Specialist for legacy system retrofit and modernisation. See Office Fit-Out, Office Refurbishment.
Hybrid systems exist — chilled beams for open-plan, VRF for meeting rooms. Adds complexity.
Measured survey and fixed-price quote within 10 working days.