Zesterex

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9 case studies

Redacted Mechanical + Electrical drawing — Cleanroom, California Drawing extract · redacted
Mechanical + Electrical Cleanroom California

ISO 8 cleanroom inside a working warehouse

A 12-sheet coordinated M&E permit set with 41% documented spare capacity — no service upgrade needed.

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ChallengeA manufacturing tenant needed an ISO 8 cleanroom built inside an operating California warehouse — without a new electrical service, and with the adjacent office left untouched. The mechanical problem was delivering HEPA-filtered air at a controlled rate through a 39-unit ceiling; the electrical problem was powering that array, its controls, cleanroom lighting and a bench of process equipment from the building’s existing 480/277V service.
ApproachWe ducted three new rooftop heat pumps directly into the fan-filter ceiling, each unit set to a fixed airflow so cooling, filtration and balance work as one system. Electrically, we kept the existing service and added a single step-down transformer and a process sub-panel, assigning every unit and luminaire to a tagged circuit, with 2022 Title 24 compliance documented.
OutcomeA 12-sheet coordinated mechanical and electrical permit set, the load calculation showing 41% spare capacity on the reused panel — proof the no-service-upgrade decision was engineered, not hoped for. First-round city comments were answered and resubmitted.
Mechanical + Electrical · California · 2025 Start a project like this
Redacted M / E / P drawing — Storage campus, Colorado Drawing extract · redacted
M / E / P Storage campus Colorado

Five-building storage campus, designed as five buildings

A 34-sheet M/E/P set across five buildings, every energy certificate passing — interior lighting up to 56% under allowance.

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ChallengeFive new buildings on one Colorado site — twenty individually owned storage units, a two-level sales-and-repair building and a car wash — each needing its own systems and 2021 IECC energy documentation. A single blended design would not permit cleanly; the AHJ reviews and inspects each building on its own.
ApproachWe designed each building as a self-contained package and the campus as the sum of them: a repeatable per-unit module — split heat pump, point-of-use water heater, full fixture group — across all twenty units, with per-building load calculations driving the services, and six energy certificates covering the five buildings plus campus exterior lighting.
OutcomeA 34-sheet coordinated M/E/P set carried through five revision rounds, every certificate passing — interior lighting 43–56% below the power allowance, exterior 98% below — with the load-calc tables printed on the drawings so the reviewer checks the math instead of requesting it.
M / E / P · Colorado · 2026 Start a project like this
Redacted Mechanical + Plumbing drawing — Detention facility, Maryland Drawing extract · redacted
Mechanical + Plumbing Detention facility Maryland

Detention facility on a vacuum waste system

A 23-sheet mechanical and 28-sheet plumbing set; right-sizing cut the kitchen system from 200 tons to 73.

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ChallengeA secure tenant improvement in Maryland across housing pods, two commercial kitchens, a laundry and medical zones — compounding the usual problems: near-100% outdoor air in sealed high-occupancy housing, a vacuum waste system that conventional drainage details do not fit, and kitchen loads large enough to swing the make-up air design threefold.
ApproachWe built a 35-system load model and refined it against the real equipment cut sheets through a documented QC review. Plumbing was designed around the vacuum sewer: detention-grade vacuum fixtures in the cells, hot water sized two ways as a cross-check, and point-of-use grease interceptors discharging to sized vacuum collection sumps.
OutcomeA coordinated 23-sheet mechanical and 28-sheet plumbing set. Refining against nameplate data cut the kitchen system from 200 tons to 73 and the laundry from 112 to 14 — right-sized systems backed by load reports the design team can hand to a reviewer, with the calculation basis printed on the sheets.
Mechanical + Plumbing · Maryland · 2026 Start a project like this
Redacted M / E / P drawing — Auto dealership, Georgia Drawing extract · redacted
M / E / P Auto dealership Georgia

Auto dealership renovation with EV charging pre-engineered

263,866 VA of demand held on the existing 1200A service — with DC fast-charging pre-engineered as a purchase, not a redesign.

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ChallengeAn operating Georgia dealership wanted a renovation layering real new load onto an existing building — a customer cafe, charging lounges, co-op spaces, an automated inspection lane, and a stated intent to add DC fast charging later — all on an existing 1200A service the owner did not want to upgrade, inside a third-party architect’s package that kept moving.
ApproachWe itemized every new and existing load in a demand calculation published on the riser sheet, reused the existing panels, and added one new panel for the renovation loads. Future EV charging was solved as a documented provision — a step-up transformer and a 480V panel sized for three 50 kW chargers — and dedicated outside-air units handle ventilation.
OutcomeThe calculation closed the question: 263,866 VA of demand — 781.5A on the 1200A main — with the EV path pre-engineered at 480V so chargers become an equipment purchase, not a redesign. The 25-sheet three-discipline set tracked the architect’s package through twenty revision cycles.
M / E / P · Georgia · 2026 Start a project like this
Redacted M / E / P drawing — Assembly lounge, California Drawing extract · redacted
M / E / P Assembly lounge California

Retail shell to A-2 assembly, sized to the people

An 11-sheet MEP package sizing every system to a re-set 261-occupant load, carried through nine revisions.

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ChallengeConverting a 6,240 sf retail shell to an A-2 bar and golf-simulator lounge re-set the occupant load to 261 — and with it every MEP requirement. The existing shell had one restroom, no assembly-grade ventilation or electrical capacity, and the occupancy change triggered a fire-sprinkler requirement that had to be routed without stalling the MEP permit.
ApproachWe sized everything to the people, not the floor area: 2,000 CFM of outside air through a single packaged unit against code ventilation rates, two new restroom groups with a recirculated hot-water loop, and a load calc totaling 109.4 kVA that set the 400A three-phase service. Title 24 forms went into the same set; the sprinkler scope was flagged on the cover for the fire department’s separate permit.
OutcomeAn 11-sheet MEP package inside the 16-sheet TI set, carried through nine revisions — with the ventilation, service-sizing and fixture calculations documented on the sheets so reviewers could check the math instead of writing comments about it.
M / E / P · California · 2026 Start a project like this
Redacted M / E / P + Fire drawing — Coastal home, California Drawing extract · redacted
M / E / P + Fire Coastal home California

Coastal custom home: radiant heat, ductless cooling, in-house sprinklers

A 25-sheet MEP set plus a hydraulically calculated NFPA 13D sprinkler set, every schedule populated by make and model.

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ChallengeAn addition and whole-house remodel on the California coast paired an existing structure with new construction behind an envelope glazed over half its floor area. The program called for radiant-floor comfort, cooling without tearing duct chases through the existing house, EV charging on a service of unknown spare capacity, and a residential sprinkler system — all against a Title 24 model and an evolving architectural background.
ApproachWe started with an ACCA Manual J/S/D run so every system was sized to the actual coastal loads. Heating became two radiant zones off one sealed-combustion appliance; cooling went to four ductless heat pumps. The service was proven by a documented load calculation, water piping sized by fixture units, and the NFPA 13D sprinkler set designed in-house alongside the MEP so the trades never collide.
OutcomeA 25-sheet coordinated MEP set plus a separate hydraulically calculated NFPA 13D sprinkler set, every schedule populated by make and model. The hydronic schematic and tabulated loop lengths pre-empt the comments reviewers raise most often on residential hydronics.
M / E / P + Fire · California · 2025 Start a project like this
Redacted M / E / P drawing — Self-storage, Texas Drawing extract · redacted
M / E / P Self-storage Texas

Three-story self-storage, built to a national prototype

Signed COMcheck certificates with lighting 24% under allowance; ten tracked revisions held the set to the operator’s prototype.

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ChallengeA national self-storage operator was adding a three-story climate-controlled building (~85,400 gsf) to a Texas site and required the MEP package to match its prototype standards exactly — per-floor electrical rooms, specific fixture packages, unpowered drive-up units — while clearing the 2021 IECC for a building type that is mostly unoccupied aisle space.
ApproachWe designed a 600A service with an identical distribution stack on each floor and lit the aisles with LED industrials on per-aisle occupancy sensors. Thirteen split heat pumps with economizers, unit heaters and a 10,000 CFM exhaust fan condition and ventilate the building; restroom plumbing rides compact risers through all three floors.
OutcomeSigned COMcheck certificates documented compliance under the 2021 IECC — interior lighting 24% under allowance, exterior 66% under, envelope 7% better than code. Ten tracked electrical revisions answered every operator review comment in writing, keeping the set aligned with the prototype.
M / E / P · Texas · 2025 Start a project like this
Redacted M / E / P drawing — Custom home, Arizona Drawing extract · redacted
M / E / P Custom home Arizona

Desert custom home with radiant slab and split cooling

Whole-house cooling at 45,921 Btuh — under 4 tons for 5,018 sf — with a 61-page ACCA load report.

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ChallengeA single-story desert custom home with vaulted ceilings, a long covered porch and a slab the owner wanted heated — at a 115°F outdoor design temperature. A single ducted system would fight the vaults in both seasons, so the house needed heating and cooling decoupled, and every piece of equipment justified by a real load number before the sheets were drawn.
ApproachWe ran a room-by-room Manual J/S/D against desert design conditions, then split the systems: a hydronic radiant slab (26 loops, two gas heaters) for heat, and three cooling zones — a ducted system for the living wing, a dedicated heat pump for the vaulted garage/shop, and a multi-zone unit serving the bedroom wing. Electrical and plumbing were coordinated to the same plan.
OutcomeWhole-house cooling came to 45,921 Btuh — just under 4 tons for 5,018 sf — verified per system in Manual S. The delivered package: 16 M/E/P sheets plus a 61-page ACCA-compliant load report, with a codes-analysis block matching the 2021 I-codes and 2020 NEC, ready for plan review.
M / E / P · Arizona · 2026 Start a project like this
Redacted M / E / P drawing — Townhouse fourplex, Colorado Drawing extract · redacted
M / E / P Townhouse fourplex Colorado

All-electric townhouse fourplex under one roof

A 28-sheet all-electric set clearing the 2021 IECC by 4.2% — no window upgrade, no gas, no ducts crossing a rated wall.

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ChallengeA four-unit, three-level townhouse building had to be heated, ventilated, wired and plumbed as four independent all-electric dwellings under one roof — with fire-rated party walls that punish every penetration, an envelope that missed the prescriptive window U-factor, and a modular-construction-friendly requirement to keep each unit’s systems inside its own box.
ApproachWe went near-ductless: room-by-room electric baseboard sized from the Manual J, one ERV per unit sized to ASHRAE 62.2, ventless dryers and recirculating hoods to eliminate exhaust penetrations, and a 600A service split into four unit panels using the multifamily demand calculation. The envelope went through REScheck as a UA trade-off rather than a prescriptive checklist.
OutcomeA coordinated 28-sheet MEP set issued through three revision cycles, with the Manual J report and REScheck certificate bound into the permit package. The building cleared the 2021 IECC at 4.2% better than code — no window upgrade, no gas infrastructure, and no ductwork crossing a rated assembly.
M / E / P · Colorado · 2026 Start a project like this

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