BMS Point List: How a BMS Installation Is Scoped in KSA

A BMS point list is the schedule of every signal the building management system reads or controls: sensors, status contacts, alarms, valve and damper commands, drive speeds. Installation is scoped and priced from that list, counted by point type (AI, AO, DI, DO), then added to panels, cabling, the supervisory layer, testing and handover documents.

The four point types

Every BMS signal falls into one of four types. An analog input (AI) is a measured value, such as room temperature, chilled water pressure, duct static pressure or CO2. An analog output (AO) is a variable command: a valve position, a damper angle, a drive speed reference. A digital input (DI) is a two-state status, like pump running, filter dirty, door open or fault. A digital output (DO) is a two-state command: start, stop, enable, alarm relay.

Most modern jobs add a fifth group. Integrated points are values read over BACnet or Modbus from equipment that carries its own controller, for example a chiller panel, a variable frequency drive or an energy meter. They need little field wiring, but they need gateway work, point mapping and testing, so they still belong on the list and in the price.

Why the point count drives the quote

Each hardware point needs a controller channel, a field device or an interface, cable, a termination, a label, a program, a graphic, alarm and trend settings, and a test record. Panels are sized to the count, and the number of panels sets the controller network. That is why a lump-sum "BMS allowance" line is hard to compare with an offer built on a point count. Two bidders can read the same drawings and count very different numbers of points, and neither will tell you unless you ask.

We don't publish a per-point rate. It moves with the point mix, cable lengths, panel type, protocol work and the testing the specification asks for, and a figure quoted without the list behind it is a guess. The offer should state the count it priced.

Reading a point list: one example

Take a chilled water pump with a variable frequency drive. A typical signal set is a DO for start and stop, a DI for run status, a DI for drive fault, an AO for the speed reference and an AI for speed feedback. If the drive has a Modbus or BACnet card, most of those collapse into integrated points on one network cable. This is an illustration only. Your specification and the equipment maker decide the real signals.

Repeat that logic across air handling units, fan coil units, VAV boxes, chillers, tanks, meters and the interfaces to lighting and the fire alarm panel, and you get the schedule the consultant should have issued.

Where the list comes from

Most consultant specifications carry an I/O summary for each system, plus sequences of operation and control schematics. Some documents give a single sentence: "BMS to monitor and control all HVAC plant". In that case a take-off from the mechanical schematics is needed, and the offer should say the count is the contractor's own and what changes in the price if the final list differs. Ask the consultant for the point schedule first. It is the quickest way to get offers you can compare.

What sits on top of the points

Points feed controllers, controllers feed the network, and the network feeds the server and workstation graphics. Open protocols matter at this layer: BACnet per ISO 16484-5 and ASHRAE 135 as typically specified, Modbus for meters and drives. The ISO 16484 series covers building automation and control systems as a whole, and the consultant's controls specification sits on top of it.

NLS Contractors scopes that whole chain as one package. See BMS installation works and DDC controls for HVAC systems, or the wider building controls and BMS service.

Where BMS programmes slip

Installation is rarely what slips. Commissioning is. Point-to-point checks need the mechanical and electrical work finished, power on, drives set up and the test and balance agency on site. If a chiller arrives late, every sequence that touches it waits. Plan BMS testing, commissioning and handover as its own block of the programme, and ask for the test procedures before the first panel is built.

What to send with your enquiry

Send the point list or BOQ, the number of buildings and floors, the protocol, and any third-party integrations (chiller, UPS, generator, lighting, fire alarm for monitoring only). Add the dates, plus the controls specification section and the sequences of operation if you have them. With those, the offer comes back with a stated point count, a panel schedule and a handover document list. Send the package.

FAQ

How is a BMS installation priced?

By the point list. The offer counts points by type, then adds panels, cabling and containment, the server and graphics, testing, training and the handover documents. The price depends on the mix and the specification, so there is no fixed per-point figure.

What is the difference between a hardware point and an integrated point?

A hardware point is wired from a field device to a controller input or output. An integrated point is read over BACnet or Modbus from equipment that has its own controller. Integrated points save field wiring but still need mapping, programming and testing.

What if the tender has no point list?

Ask the consultant for one. If none exists, the contractor can count from the schematics and state the basis. Compare offers on that stated count, not on the total alone.

Which documents come at handover?

Shop drawings, panel and I/O schedules, point-to-point test records, controller programs and backups, as-builts, O&M manuals and a record of operator training.