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Upgrade your building while it stays in use
The work goes floor by floor while the rest of the building carries on. Plant controllers and wall switches stay, and we choose wired, wireless or hybrid from our portfolio, whatever gets your building to a return in under 3 years with the least disruption. One BMS runs it all. At Liivalaia in Tallinn, a 22,000 m² office complex, energy use fell 30% after the retrofit.
Less energy. One platform. 30-40% lower cost. ROI in under 3 years.
Energy savings first
Energy is the first return on a retrofit: about 10% from room-level control, about 21% with hydronic balancing and another 11-13% from forecast-based plant control. Liivalaia in Tallinn used 30% less energy after its full Bisly retrofit.
One platform, one responsible provider
No stack of software and hardware suppliers to coordinate, and one party answerable for the result.
30-40% lower cost of acquisition
Optimised devices and a deployment configured in the digital twin take the engineering hours out of the project, so the building gets a complete system for less.
ROI in under 3 years
The energy saved pays the system back in under 3 years, and regulation now requires building automation anyway.
Non-residential buildings with heating or cooling above 290 kW have needed building automation since 31 December 2024. By 31 December 2029 the threshold drops to 70 kW (Germany: GModG; elsewhere in the EU: EPBD).
Wired, wireless or hybrid: whatever pays back fastest in your building
We do not sell one technology. We look at what is in the building today and pick from the whole Bisly portfolio the mix that reaches a return on investment in under 3 years with the least disruption for the people working there.
Wired
Where the building is being stripped back anyway, or the cabling is already there: Bisly controllers, room controllers and DALI-2 lighting, pre-configured from the digital twin.
Learn moreWireless
Where cabling would mean opening ceilings and closing rooms: clip-on valves, battery sensors and wireless meters on a Wi-SUN and Matter network, installed in days while rooms stay in use.
Learn moreHybrid
Most retrofits: the plant room and risers wired, the floors above wireless, or wired floors where a refurbishment is planned and wireless everywhere else. Both run in the same BMS, app and digital twin.
Solutions that fit existing buildings
Wireless retrofit
Where new cables would mean opening ceilings and closing rooms, battery sensors and wireless valves take their place. Wireless floors show up in the same BMS and app as wired ones. Taking orders now.
Explore wireless retrofitEnergy monitoring
Metering is often the first step, so you see where the energy goes before you change anything. Heat, electricity and water meters are read remotely, empty units included. Remote reading of heat meters becomes mandatory in Germany by 31 December 2026, and across the EU under the EED, including Poland, from 1 January 2027.
Explore energy monitoringScalable building automation
The heating plant, air handling units and chillers keep the controllers they have, and Bisly connects to them. The plant room and every floor, wired or wireless, then run in one BMS, so your team learns one system.
Explore scalable building automationWhat gets added, and in what order
A retrofit usually starts where nobody works: the plant room and the meters. The rooms follow floor by floor, so people on the other floors carry on as normal.
Metering
Every meter is read remotely, with no visits to read them. Consumption is split per tenancy and by day and night, and a sudden spike raises an alarm.
Plant room
The plant you have keeps its own controllers. Bisly reads them, sets them and shows them live. AHUs from more than 20 manufacturers are already integrated. If the connection drops, the plant runs on by itself.
Alarms
Plant faults go straight to the facility manager or the service company by SMS or e-mail, with priorities and delays that ignore short spikes. Adam flags faults and explains them in plain language.
Schedules
Ventilation and heating run to the hours the building is used, holidays included, from one calendar.
Heating & cooling
Every room gets its own temperature control, one floor at a time. Finished floors run in the BMS while the work moves on to the next one.
Fresh air
CO₂ sensors in each room tell the existing air handling units how much air to send, so they stop sending full airflow to empty rooms.
Lighting
Where the cabling allows it, lighting moves to DALI-2 with groups and scenes. Elsewhere, the existing switched and dimmed circuits are controlled as they are.
Wireless rooms
Where cabling would mean closing a room, battery sensors and wireless radiator, fan-coil and floor-heating valves are used instead, each added by scanning its QR code. Wireless floors appear in the same BMS and app as wired ones.
Savings and payback
energy use at Liivalaia, Tallinn, after the full Bisly retrofit
more saved by running the existing plant on forecast-based control, on top of room control
return on investment
Retrofit projects
Swedbank's former head office, now let to several tenants. Automation was added in phases while the building was in use: meters first, then the plant room, then the rooms. Energy use down 30%.
View projectAn existing office building retrofitted with heating, access and blinds control, DALI and on/off lighting, and Bisly Hubs for tenants.
View projectAn existing building reconstructed as a community centre, with room-by-room heating control, remote monitoring and meter reading.
View projectRetrofitted with DALI/TRIAC lighting automation and full BACS; 20-35% energy savings.
Upgrading a building that is in use?
Tell us what is in it today: the plant, the meters and how the rooms are wired. After a 30-minute call, we work out what can stay and send the scope and a fixed price within 5 working days.