When to bring a KNX integrator into a project: the RIBA stages

At what RIBA stage should a KNX integrator be brought into the design team? On a complex residential, later living, BTR, or commercial project, the answer is Stage 2 or 3.

Bringing the integrator in later is the most common specification timing mistake we see. It costs capability, coordination time, and budget, in that order. This post walks through what the integrator should be doing at each RIBA stage, and what changes when they arrive late.

The short answer

For any project where KNX is the protocol and the building is more complex than a single-zone home or a standard fit-out, the integrator should be appointed at Stage 2 alongside the M&E consultant and the lighting designer. The latest acceptable point is early Stage 3. After that, the integrator is fitting a system into a building that was not designed for it.

Stage 0 to 1: strategic definition and preparation

There is no integrator appointment yet. The work at these stages is the client’s brief and the design team’s initial feasibility studies. What matters for automation is that the brief acknowledges it.

A brief that says “the building should support automation” is too thin. A brief that names the scope, even at the level of “KNX-based automation for lighting, climate, blinds, and integration with security and AV”, gives the design team something to work to.

For later living and BTR schemes, the brief should also reference the operational platforms the system will need to integrate with: telecare, BMS, access control, resident apps. For super-prime residential, it should reference the appointed lighting designer’s involvement.

The M&E consultant typically picks this up at Stage 1. If automation is in the brief at this point, the integrator can be appointed at the start of Stage 2.

Stage 2: concept design

This is when the integrator should be appointed.

At Stage 2, the architect develops the spatial concept and the M&E consultant develops the engineering concept. The integrator’s role at this stage is to:

• Establish the automation scope alongside the M&E package
• Identify integration requirements with third-party systems (telecare, BMS, AV, security, access control, specialist climate, pool plant)
• Contribute to the lighting design philosophy with the lighting designer
• Set the broad system architecture, including KNX backbone, gateways, and control hierarchy
• Attend design team meetings and respond to queries from the architect and M&E consultant

The output at Stage 2 is a concept-level control philosophy document, issued through the M&E consultant alongside the rest of the design team output.

Stage 3: spatial coordination

Stage 3 is where the integrator earns most of their early-stage fee.

The architectural and M&E layouts are coordinated in detail. The integrator’s role is to make sure the automation cabling, device locations, control points, and integration interfaces are coordinated into those layouts:

• Bus cabling routes within the M&E containment
• Sensor, switch, and control plate locations on the architectural plans
• Coordination with the lighting design for dimming protocols, driver locations, and scene structure
• Coordination with the AV designer for control interfaces
• Coordination with the M&E consultant for HVAC zoning, BMS interfaces, and electrical capacity
• Coordination with the security and access control consultants

The output at Stage 3 is a detailed control philosophy, an integration matrix listing every third-party interface, and coordinated drawings issued through the M&E consultant.

If the integrator is not in the design team at Stage 3, these coordinations either do not happen or happen retrospectively on site.

Stage 4: technical design

At Stage 4, the design is taken to construction-ready detail. The integrator issues:

• The detailed KNX schematic
• Device schedules
• Updated integration matrices
• Programming logic and scene structure
• As-tender documentation for the project electrical contractor

Documentation is issued through the M&E consultant in formats that align with the rest of the design team output: drawings to the same scale and standard, schedules in the consultant’s format, control philosophy in the house style where required.

This is also the stage where the procurement strategy for the KNX hardware is set. Long-lead items are identified and ordered.

Stage 5: construction

On site, the project electrical contractor installs the KNX bus cabling alongside the lighting and small power, working from the integrator’s drawings. The integrator attends first fix and second fix, coordinates on site, and resolves queries between trades.

On a Baulogic Bespoke project the electrician installs the infrastructure. The integrator owns the system and remains accountable for it through commissioning. That distinction matters when something does not work: there is one team to call.

At second fix, the integrator programmes and commissions the system. This is where Stage 2 to 4 design work pays off. Scenes, schedules, integrations, and resident-facing controls go in to a system that was designed for them.

Stage 6 to 7: handover and use

At handover, the integrator issues as-installed documentation through the M&E consultant: updated schematics, programming exports, integration matrices, and a system manual for the operator or end client.

Aftercare is part of the integrator’s engagement rather than a separate contract negotiated at handover. For a long-hold asset the support agreement covers responsive maintenance, scheduled updates, and changes the operator wants to make as the building runs.

What happens if the integrator joins at Stage 5

The integrator can still deliver a working system. What is lost is the coordination work that should have happened at Stages 2 to 4:

• Cabling routes have to be retrofitted into containment designed without them
• Sensor and device locations are constrained by ceilings and joinery already specified
• Integration with third-party systems happens through workarounds rather than protocol-level coordination
• The lighting design and the control design are reconciled retrospectively
• The M&E consultant carries coordination queries the integrator should have answered six months earlier

When the integrator joins at Stage 5 or later, the recoverable scope is meaningfully smaller than what a Stage 2 appointment would have produced. A working system can still be delivered. The system a coordinated design process would have produced cannot.

The cost increases. The capability decreases. The design team carries more risk through the closing stages of the project.

The implication for design teams

For a complex residential, later living, BTR, or commercial project where KNX is the protocol, the integrator belongs in the appointment schedule at Stage 2.

The practical steps for the design team:

• Reference automation in the brief at Stage 0 to 1
• Identify the integrator alongside the M&E consultant and the lighting designer at Stage 2
• Treat the integrator’s output (control philosophy, integration matrix, schematics) as part of the M&E consultant’s design coordination
• Include the integrator in design team meetings and design queries from Stage 2 onward
• Expect documentation through the M&E consultant in formats that align with the rest of the design output

Bringing the integrator into the design team early is the simplest way to get a coordinated, well-specified KNX system on a complex project. The work is more design than install. Specifying it that way produces a better building.