Commercial & Office
A commercial office is leased before it's finished and re-leased every few years after. The MEP has to serve a tenant you haven't met yet — sized for a load you can only estimate, zoned for walls that don't exist, and metered so the next fit-out doesn't start from zero.
Designed for the Next Tenant — Not Just This One.
Core-and-shell and tenant improvement are two different problems, and we design both as one system. The shell sets the plant capacity, riser space, and zoning every fit-out inherits; the TI has to clear plan check on a leasing deadline. We size HVAC to real diversified load and electrical service to the NEC Article 220 calculated load — not nameplate — design to ASHRAE 90.1 and the local energy code, and keep systems flexible enough that re-stacking a floor doesn't mean re-engineering the building.
Core & Shell vs. Tenant Fit-Out
We design the base building and the tenant spaces as one coordinated system, not two disconnected sets.
- Central plant, riser, and shaft capacity sized for full build-out and diversified peak
- Tenant utility stub-outs, CT/submeter provisions, and demising-wall coordination
- Spec-suite and white-box documentation that drops in for faster leasing
- TI designs that land within the shell's reserved CFM, tonnage, and amperage
- Landlord/tenant scope splits aligned to the lease work letter and demising line
A worked split: the shell set carries the central plant, risers, main electrical distribution, and the reserved CFM, tonnage, and amperage per floor; the tenant set carries the terminal units downstream of the riser tap, panel and branch circuiting downstream of the floor panel, and lighting controls for the demised space. Which side each item falls on is written into the criteria package, aligned to the lease work letter.
Energy Code & Performance
Energy code compliance weighs heavily on office projects — a failed compliance path can stall a permit, and exceeding a carbon cap can cost the owner each year.
- ASHRAE 90.1 / IECC compliance — prescriptive and envelope trade-off paths documented in COMcheck, performance path via whole-building energy modeling (IECC C407 / ASHRAE 90.1 Appendix G)
- Local overlays — California Title 24, NYC Energy Code and Local Law 97 carbon caps, state stretch codes
- Demand-controlled ventilation where the energy code requires it (90.1-2019 §6.4.3.8: spaces over 500 ft² at 25+ people per 1,000 ft²; 2021 IECC C403.7.1: spaces over 500 ft² at 15+ people per 1,000 ft²; both have system conditions and exceptions, and later editions change these triggers) and where it pays elsewhere — engineered per ASHRAE 62.1 with CO2 reset that never drops below the area-based outdoor-air minimum
- Daylight-responsive dimming, occupancy sensing, and automatic receptacle control per 90.1
- Building-level energy monitoring where required by the adopted energy code
- Tenant submetering for cost recovery, benchmarking, and disclosure ordinances
HVAC Systems & Comfort
Open plans, glass facades, and variable occupancy make office load anything but uniform.
- VAV, VRF, water-source heat pump, and fan-coil system selection and zoning
- Thermal comfort per ASHRAE 55 designed alongside the energy budget, not traded against it
- Separate perimeter and interior zoning to absorb solar and glass-load swings
- Rooftop unit (RTU), WSHP loop, and central chilled-water plant options weighed against the program
- Airside/waterside economizer and after-hours tenant override controls
- BAS / DDC controls with documented Sequences of Operation (SOO)
- Block and zone load calculations tied to the actual envelope and orientation
Power, Lighting & Low-Voltage
Power has to be there for a tenant whose layout doesn't exist yet.
- Service and distribution sized to diversified tenant load per NEC Article 220
- Lighting power density (LPD) budgeted per ASHRAE 90.1/Title 24, with automatic controls to match
- Floor-by-floor panel, busway, and riser strategy with spare capacity
- Lighting design to ANSI/IES RP-1 office illuminance with code-compliant controls
- Tenant power, data, AV, and security rough-in pathways and back-boxes
- EV-ready parking, emergency power for life-safety loads, and optional standby power for critical tenant loads
- Grounding, bonding, and surge protection for IT-dense fit-outs
Plumbing & Fire-Protection Coordination
Core restrooms, breakrooms, and fire systems that can flex with re-stacks.
- Domestic water, sanitary, and storm design to the IPC or UPC
- Core restroom layouts planned for flexible re-stacks
- Core restroom fixture counts and tenant breakroom rough-in
- Domestic hot-water heating and recirculation sized to occupancy
- Fire-sprinkler coordination with the fire-protection engineer per NFPA 13
- Backflow prevention and grease/oil interceptors where tenant use requires
Yes — and we design them as one system. The core-and-shell set establishes the plant, riser capacity, and zoning every tenant inherits; the TI lands within that envelope on the leasing schedule. Doing both under your engineer of record's direction and seal means each fit-out is designed against the shell decisions already on record, which keeps re-stacks quicker and less costly. We track reserved CFM, tonnage, and amperage per floor to guard against double-counting capacity across suites.
We design to the jurisdiction's adopted energy code — the IECC, or ASHRAE 90.1 where it's elected as the alternative path, in most states; the NYC Energy Code for New York City projects; Title 24 Part 6 documented on CEC forms for California. We confirm the AHJ's adopted code edition up front, because that drives DCV thresholds, receptacle controls, and economizer rules, and we track the additional carbon and stretch requirements — Local Law 97, state stretch codes — where they apply. The compliance path is documented in the set so the submittal matches what the reviewer is enforcing.
Actual diversified load. Sizing office HVAC and power to nameplate inflates equipment, energy, and first cost, and it strands plant capacity the owner paid for. We use realistic occupancy, plug-load, and lighting densities, with NEC Article 220 calculated loads and demand factors as the floor for feeders and service and project-specific diversity applied to HVAC plant sizing, then document the assumptions so the licensed engineer of record on your project can review the basis of design quickly.
Yes — it's some of the fastest-moving work we do for office clients. We keep a coordinated shell basis of design so each suite drops in without re-deriving capacity, which is how landlords hold leasing velocity up across a building. Spec suites, white-box, and warm-shell scopes are documented to whatever level your leasing strategy calls for.
We document the demising line clearly — what the base building provides (capacity, stubs, metering) versus what the tenant's TI carries — aligned to the lease work letter. That keeps change orders and finger-pointing down once the tenant's contractor mobilizes. The matrix travels with the criteria package so every tenant engineer builds from the same assumptions.