What is a master systems integrator and when is one needed?

When the room-booking system fails to turn the ventilation down, whose problem is it? On a building with systems from several contractors, each can usually prove that its own part works, and nobody is answerable for the connection between them. That gap is the job of a master systems integrator (MSI): the party responsible for making a building's separate technology systems work together as one. The MSI designs and builds the integration layer, agrees the data and interface details with each system contractor, sets naming and data standards, runs the integrated tests and often supports the integrated platform after handover.

An MSI is needed when several systems from different contractors must share data or act together to deliver the use cases, and nobody else is contractually responsible for the result. The role should be considered during spatial coordination and appointed by technical design at the latest, in a position that gives it the authority to require information from the other contractors.

The scope of the role

The RIBA Smart Building Overlay to the Plan of Work describes MSIs as making sure all systems communicate properly. In its description they work with building owners so that system information is accessible and usable, and they develop the software layers responsible for integration, aggregation and communication between building systems. On a typical project the scope includes:

• the integration architecture and the platform or middleware that connects systems;
• interface schedules agreed with each system contractor;
• a naming, tagging and data model standard that every package must follow;
• prequalification of proposed products against the integration and security requirements;
• configuration of dashboards, applications and data feeds defined in the use cases;
• coordination with the owner's IT team on networks, hosting and security;
• integrated and failure testing across packages;
• handover documentation for the integrated layer, and often ongoing support.

The overlay recommends considering whether a project would benefit from an MSI at Stage 3, Spatial Coordination. It recommends that an MSI work alongside the smart building specialist from Stage 4, Technical Design, and that specified technologies be prequalified by the MSI, either through a desktop exercise or through factory mock-ups by the supply chain.

How it differs from the consultant and the controls contractor

Some firms can perform more than one of these roles, but combining them on the same project needs care. An MSI that also wrote the specification is reviewing its own design, and a BMS contractor acting as MSI may favour its own products when integrating everyone else's.

Signs that a project needs one

The case for an MSI builds as the conditions accumulate. Several systems from different contractors have to exchange data or act together. Key use cases depend on more than one system, such as occupancy-driven ventilation, lighting and booking. The owner wants a single operational platform or data layer covering every system. The building will be multi-tenanted or will change use over time. Or the owner intends to extend the same approach across a portfolio. When several of these are true, an MSI is usually worth its fee.

It may not be needed where one contractor supplies most of the systems with few interfaces, where the use cases are confined to a single system, or where the owner's IT or facilities team already runs an integration platform and can extend it. Even then, integration responsibility should be assigned explicitly to an existing party. Left unassigned, it belongs to nobody.

Where to place the appointment

Whichever route is chosen, every system contractor's contract should oblige it to provide the data, interface documentation, test support and access the MSI needs. Without that obligation, the MSI has responsibility without authority.

An integrator with access to everything

An MSI has broad access to building systems, often including remote access, which makes its own security practices a legitimate subject for the owner. IEC 62443-2-4, in its current 2023 edition, sets out the security-related processes a service provider can offer an asset owner during integration and maintenance of an automation solution, and it is a useful reference when writing MSI requirements. CISA and the FBI also advise owners to keep the ability to recover their systems and operate without the integrator. That matters more for an MSI than for any other supplier, because it touches every system. Bidders should be asked to describe their own internal security practices alongside those they will apply to your building.

The job continues after completion

The MSI's work does not end at practical completion. Integrations break when systems are upgraded, and new use cases need configuring. The owner has to decide whether the MSI will provide ongoing support, on what service levels, and how knowledge will be transferred if the role moves to another provider or to the owner's own team.