TIs Are the Most Common MEP Project Type
Commercial tenant improvement projects — new tenants moving into existing space, business expansions, building renovations — represent the most common category of commercial construction. And nearly all of them require MEP engineering. Here's how to understand what's needed for your TI.
Mechanical Engineering for TIs
The mechanical scope depends on what's changing. Common TI mechanical scope includes:
- HVAC modifications or additions — new zones, relocated equipment, rebalancing
- Exhaust systems for new occupancies (restaurants, medical, lab, industrial)
- Outside air calculations for new occupancy loads
- Title 24 or ASHRAE 90.1 energy compliance for altered systems
If the existing HVAC is being reused and the occupancy load doesn't change significantly, the mechanical scope may be limited. If the space is being changed to a higher-ventilation use (dining, clinic, gym), a full mechanical redesign may be required.
Electrical Engineering for TIs
Electrical TI scope typically includes:
- Load calculations confirming the existing service is adequate (or designing an upgrade)
- Panel schedule updates for new or relocated circuits
- Lighting design for remodeled spaces
- Dedicated circuits for new equipment
- EV charging, if required by the local code for new TIs
Plumbing Engineering for TIs
Plumbing scope is driven by fixture changes and occupancy type:
- New restrooms or relocated fixtures
- Kitchen or break room additions
- Gas piping modifications
- Specialty systems (grease interceptors, medical gas, lab plumbing)
When to Start MEP Engineering
Start MEP engineering as early as the architectural layout is established — you don't need final drawings to begin. Waiting until architectural documents are complete before engaging MEP engineers is the most common cause of permit delays on TI projects. Early engagement allows the MEP engineers to identify conflicts, flag equipment room requirements, and coordinate systems before the architectural layout is locked.