Does a Tenant Improvement Need a PE Stamp?

TI structural work is surgery on someone else's building, and the review treats it that way. I start by establishing what exists: the structural system, which walls are bearing, where the lateral elements are, and what the floor structure can carry. Proposed openings get analyzed for their effect on gravity and lateral behavior — a new storefront in a shear wall line is a lateral redesign, not a header schedule. New loads get checked against the existing structure's capacity: the rooftop unit on the TI's new HVAC, the file room's floor loading, the equipment platform. Every structural modification gets designed, detailed, and sealed as its own engineered scope within the TI set. In seismic jurisdictions — California TIs especially — the lateral check is the heart of the structural review. Openings in shear walls, removed wall segments, and added mass all change the building's seismic behavior, and the code's existing-building provisions govern what's permitted. I verify the TI's lateral design against those provisions, detail the connections and holdowns the modification requires, and confirm the work doesn't trigger a broader seismic retrofit the owner didn't budget for. That last check — scope containment — is the TI structural review's most valuable deliverable.

The MEP review is a capacity study wrapped in a design review. I calculate the TI's new loads — cooling and heating for the reconfigured space, lighting and receptacle, specialty equipment from dental chairs to commercial cooking — and verify each against the base building system's documented capacity. HVAC gets the load calculation and a check that the existing system can deliver the air and the conditioning: zone by zone, not just in total tons. Electrical gets the panel and feeder analysis with the TI's loads added as the code requires. Plumbing gets fixture counts against the riser capacity and the sanitary system's ability to accept the new fixtures. Where the TI changes the space's use — retail to restaurant, office to medical — the MEP review essentially becomes new-construction engineering inside an existing shell, because the load profiles are entirely different. Grease waste, medical gas, added ventilation: the TI set designs these as new systems connecting to base building infrastructure, and the PE verifies both the new design and the connection point. Landlord approval of the MEP scope runs alongside the engineering, since the base building systems are the landlord's asset.

A TI submittal is ready for the PE's seal when the design respects the base building's realities. The fastest TI permits come from verifying capacity before designing, not after. • Base building structural, MEP, and permit documents obtained — or field verification scoped where they're missing • Proposed demolition verified against the structural system: no load-bearing surprises • New openings and added loads structurally designed, with lateral effects checked in seismic jurisdictions • TI MEP loads calculated and verified against base building electrical, HVAC, and plumbing capacity • Accessibility scope for the alteration addressed, with structural and Method implications coordinated • Landlord approval of structural and MEP scope secured alongside the engineering