Is an MSI actually cheaper than letting the BMS contractor own integration?

On capex, an MSI costs 3-6% of converged-systems budget. On opex over a 10-year horizon, an MSI-led integration typically returns 2-3x that figure in avoided remediation, reduced energy waste from misaligned setpoints, and reduced incident-response time. The trade is upfront cost for downstream certainty.

When the MSI is the right call

• Three or more disciplines need to converge (HVAC, electrical, life-safety, security).
• Operational continuity depends on cross-system behaviour.
• The client team isn't large enough to police integration in-house.

If your project is one BMS vendor's platform with a couple of sensors hanging off it, you don't need an MSI. If it's a Tier IV data hall or a pharma campus with five-vendor BMS estate, you can't afford not to have one.