The single biggest factor in choosing hotel room control is often not the technology — it is the installation cost and disruption. Wired RCU (KNX or RS-485) delivers a robust, long-life backbone but needs cabling; BLE Mesh removes the cabling entirely. This article compares the two on the numbers that matter to owners and integrators.
Where the cost actually sits
| Cost driver | Wired RCU (KNX / RS-485) | BLE Mesh wireless |
|---|---|---|
| Cabling & conduit | Significant (bus + mains) | Minimal (existing 220V only) |
| Labor | High (electricians, wall openings) | Low (surface / near-load mount) |
| Device cost | Mid–High | Mid |
| Disruption | High (new build or full strip-out) | Low (room-by-room, occupied) |
| Commissioning | Medium | App-based, fast |
Per-room economics
In a new build, the bus cable is laid during construction when walls are open, so the marginal cost of wiring is small — wired RCU (especially RS-485) is very cost-effective there. In an operating or renovation property, the same wiring means opening walls, moving guests and lost room-nights; BLE Mesh typically wins on total project cost because labor and disruption dominate.
When each pays back fastest
- Wired RCU: best lifetime value for new hotels and chains planning 15–20+ year operation.
- BLE Mesh: fastest payback for retrofit, where avoided rewiring and kept occupancy outweigh device differences.
Don't forget the operational savings
Both approaches deliver the same energy and service gains through a GRMS: card-power HVAC cut-off, occupancy lighting, DND/MUR efficiency and remote fault detection. Those recurring savings — not the one-time hardware — usually justify the project. See how hotel RCU cuts energy costs for the breakdown.
Frequently asked questions
- Is BLE Mesh "cheaper" in a new build?
- Not necessarily — in new construction the wiring is cheap to add, so a wired RCU often has the better lifetime cost. BLE Mesh wins when rewiring is impractical.
- Can I mix both?
- Yes. New wings wired, old wings on BLE Mesh, unified under one GRMS. See KNX vs RS-485 vs BLE Mesh.
- What about reliability over time?
- Wired has the edge on raw robustness; BLE Mesh relies on good gateway placement, confirmed by a quick site survey.