Ask three vendors what your hotel needs and you’ll hear three acronyms: EMS, GRMS and “smart room.” They overlap, and the difference matters. It decides what you install, what your brand will accept and how much waste you actually take out of the room.
Here’s the plain-language version we walk owners through during a free assessment.
EMS: smart thermostats & energy controls
A guestroom energy management system (EMS) controls heating and cooling. Smart thermostats & energy controls work with an occupancy sensor (and often a door sensor), so the room knows when nobody is in it and eases back to a setback temperature. When the guest returns, it recovers before comfort suffers.
EMS is the foundation. It’s where most of the energy savings come from, because HVAC is the biggest energy user in a typical guest room.
GRMS: the whole room, connected
A guest room management system (GRMS) starts with the same energy controls and connects everything else in the room:
- Lighting with arrival scenes, master off and nightlights, built for brand requirements
- Door locks, so entry, departure and checkout drive the room’s state
- DND/MUR and room status that housekeeping can act on
- PMS integration, so the room knows whether it is sold or unsold
- BMS integration, so engineering sees guestroom demand next to the central plant
- A central dashboard with alerts for offline devices and problem rooms
The difference is information. An EMS room knows whether someone is moving inside it. A GRMS room knows whether it’s sold, whether the guest just walked in, whether the balcony door is open and what the plant is doing.
Which one does your property need?
It’s rarely all or nothing. We specify room by room:
- Select-service and extended stay: smart thermostats & energy controls in every room, often with PMS integration for unsold-room setback.
- Full-service and lifestyle: full GRMS in suites and premium rooms, energy controls in standard rooms, all on one platform.
- Brand-mandated rooms: whatever the current brand standard calls for, which may include lighting behavior and connected-room features.
- New builds and major renovations: the cheapest time to wire for full GRMS, even if you phase it in.
The rule we use: start where the savings are, and design the first phase so the next one doesn’t rip anything out.
What it saves
On average, properties see 20–35% lower guestroom HVAC energy use, with a typical payback of 12 to 18 months, often sooner with utility rebates.* Integrated rooms tend to land toward the upper end of that range because setback happens more reliably. A door event is a surer sign than a motion timeout, and a PMS status is surer still.
Your property may qualify for 74 verified utility rebate programs and more. We verify that for free.
Questions to ask before you buy
- Is it fitted to our HVAC, or are we fitting our HVAC to their catalog?
- Can it grow from EMS into full GRMS on the same platform?
- Can they perform PMS and BMS integrations, and who owns the interface if something breaks?
- Who commissions every room, and what happens after go-live?
FAQ
Is GRMS just a more expensive EMS? No. EMS handles HVAC. GRMS adds lighting, door locks, DND/MUR, PMS and BMS integration and central control, serving operations and brand requirements as well as energy.
Can we start with EMS and add GRMS later? Yes. We design the first phase so devices, wiring and network are ready for the next one.
Can a GRMS be added to an existing hotel? Yes. Most of our work is retrofit, using wireless devices where they limit wall work, installed floor by floor around your occupancy.
Can you integrate with our PMS and BMS? Yes. We can perform BMS and PMS integrations as part of an EMS or GRMS project.
See what your rooms need
Our free assessment looks at your rooms, your HVAC, your brand standard and your systems, then gives you a room-by-room plan. Learn more on our GRMS page or see how integration works.
Book your free assessment → or call our team at (561) 762-9500
*Savings and payback vary by utility rates, climate, HVAC type, occupancy and available rebates. Results vary. Rebate amounts, approval and timing are set by each utility and can change; we confirm eligibility for your exact address before you commit.
