InPlant Offices
Modular Building Systems

Volume I · A field guide to modular building systems

A finished office,
dropped into a working plant.

Customized 3-inch modular building systems in painted steel or anodized aluminum. Clear spans to forty feet, load-bearing roofs to 125 psf, factory-prefabricated for clean installation, and engineered to expand or relocate as your operation grows.

Request a Quote 1-800-637-9508

EfficiencyFlexibilitySafetySound ControlEnvironmental ControlTime-SavingFaster Return

Introduction
—
2026 catalog

Since 1987, InPlant Offices, Incorporated has manufactured prefabricated modular building systems for in-plant offices, mezzanines, equipment enclosures, cleanrooms, and pre-assembled booths. Every system arrives factory-painted and palletized on motor freight, installs around your equipment in five to seven weeks from order, and remains non-progressive — meaning walls, doors, and panels can be swapped, expanded, or relocated later without disturbing what stands next to them.

01 — In-Plant Offices & Buildings

A clean workspace, built around the production line.

From a single one-person shipping office to a multistory warehouse complex with a load-bearing roof, InPlant systems are fabricated to a fraction of an inch and installed around existing equipment. Standard Steel handles single-story interior offices and partitions. Heavy-Duty Steel and All-Purpose Aluminum carry second floors and warehouse storage overhead.

The 3″ wall panels include sound-controlling, non-combustible, and load-bearing options, and the modular building system stays expandable — adding a window, swapping a door, or splitting a room is a panel-level change, not a teardown.

Four warehouse management offices in a row, white steel-faced panels with fluorescent ceiling lighting visible through windows — Plate 01Four warehouse management offices, Standard Steel System with 3″ Painted Gypsum Wall Panels.

InPlant supervisory enclosure with full glass for vision into controlling equipment, painted yellow safety rail — Plate 02Supervisory enclosure with full vision glass and yellow safety rail.

Showroom-style InPlant office with floor-to-ceiling glass framing a vintage automobile display — Plate 03Showroom build with full-height glazed panels.

02 — Mezzanine & Vertical Expansion

Reclaim the air above your floor.

Heavy-Duty Steel and All-Purpose Aluminum systems carry second-story offices, upper-deck workspace, and warehouse storage on integral load-bearing roofs — recessed I-beams on 48-inch centers, supporting up to 125 pounds per square foot.

Stair systems, ladders, gates, and handrails are engineered as a package. Demountable partition systems stack panels to extend height, can be field-modified, and lock together with the same non-progressive logic — so the office you build today can become two next year, or move entirely without losing the panels.

Two-story InPlant office with yellow steel staircase, white painted gypsum wall panels, observation windows looking onto the production floor below — *Plate 04 —* Second-story office over an active in-plant shop, Heavy-Duty Steel System with painted gypsum panels and a yellow steel staircase.

03 — Equipment Enclosures

Containment built around the equipment.

3-inch steel-faced wall panels and steel building systems form durable safety barriers around lasers, welding cells, paint and powder coating booths, grinding rooms, compressors, and robotic automation. Omit one or two panels during installation to position large equipment, then close the wall back up.

Wiring studs include integrated raceways for electrical and data; hard-cap roofs accept extraction systems and roof-mounted accessories. Light-tight construction, laser-protective glazing, computer-programmed door controls, and interlocks are all available.

Laser safety enclosure sized for laser equipment, with bright orange light-tight door and white steel-faced wall panels — Plate 05Light-tight laser enclosure with protective glazing.

Tall InPlant enclosure with Soundstop wall panels containing noisy production equipment — Plate 06Tall Soundstop™ enclosure with rock-wool insulated panels.

20 gauge Standard Steel System and 3″ painted Gypsum Wall Panels in an elevated supervisory enclosure — Plate 07Supervisory enclosure with full electrical raceway.

04 — Cleanrooms & Controlled Environments

ISO-rated rooms that work with your air-handling spec.

3″ All-Purpose Aluminum with FRP-faced wall panels gives a moisture-resistant, non-corrosive, easy-to-clean cleanroom shell with strong load-bearing support for ancillary equipment. Heavy-Duty Steel handles load-bearing builds, more insulation, and sound attenuation. Wall panels integrate easily with the stringent equipment requirements for ISO-rated cleanrooms.

Air handling is paramount — InPlant partners with the best cleanroom specialists for positive-pressure rooms, negative-pressure rooms, antechambers, and air showers. For CMM rooms, calibration labs, and washdown agricultural environments, the 3″ systems hold temperature, pressure, and humidity tolerances while remaining easy to clean.

Temperature-controlled, dust-free white cleanroom interior with seamless wall panels, recessed lighting, equipment row — Plate 08Temperature-controlled, dust-free white room.

Medical response trailer interior with stainless steel sink, FRP faced wall panels, dispenser and overhead exam light — Plate 09Medical response trailer — Aluminum System with 3″ FRP panels.

From a single 4-foot-wide partition to a wafer-fab cleanroom infrastructure, InPlant fabricates the same 3-inch panel system to the same fraction-of-an-inch tolerance.

— On the modular method, page 9 of the brochure

05 — Pre-Assembled Shelters & Booths

Ships fully assembled. Lands with a forklift.

Guard shacks, ticket booths, gate houses, and field observation shelters arrive wired, glazed, and ready to set in place. Built on a welded steel channel base frame with fork pockets — up to 8 feet wide by 20 feet long on a standard truck, larger on oversized freight.

For exterior duty, InPlant pairs the All-Purpose Aluminum building system with 3″ cement-board wall panels and exterior-grade corrugated roofing with a perimeter gutter system. Bullet- and blast-resistant construction is available with integrated security cameras, access-control doors, and more.

Large 12x20 foot exterior modular booth, All-Purpose Aluminum System with insulated Cement Board Wall Panels — Plate 1012 × 20′ exterior booth — Aluminum with Cement Board panels.

Custom-painted yellow InPlant booth on forklift, with windows and steel door — Plate 11Custom paint, color-matched to facility branding.

Modular wall panels and components packaged for shipment on fork-pocketed wooden pallets — Plate 12Packaged for motor freight with inventory list & CAD drawings.

06 — Building Systems

Three systems. The same modular logic.

Pick the structural system by load, environment, and span. All three carry 3″ wall panels, route electrical and data through integrated wiring studs, and remain non-progressive — panels swap and walls relocate without disturbing what stands next to them. Wiring studs are spaced every 4 feet or less; cover plates expose the wiring raceway from either side.

System IStandard Steel

20 gauge steel wiring stud cross-section with friction-fit cover plates

20 gauge non-load-bearing steel for single-story interior partitions, in-plant offices, and equipment enclosures. The most economical structural choice. Friction-fit steel cover plates give access to wiring tracks from either side of every stud.

Gauge20 ga steel LoadNon-load-bearing Best forInterior partitions · single-story offices · enclosures FinishWhite / gray / beige neutrals or custom paint

System IIHeavy-Duty Steel

16 gauge load-bearing steel — InPlant's strongest system. Carries two-story buildings, supports load-bearing roofs for storage and production, and produces the widest column-free spans available: up to 40 feet in non-load-bearing applications.

Gauge16 ga steel LoadLoad-bearing Best forTwo-story builds · 40′ spans · roof loads to 125 psf FinishCustom paint match or contrast

System IIIAll-Purpose Aluminum

All-Purpose Aluminum Wiring Stud, 6063-T5 anodized extrusion

6063-T5 anodized aluminum extrusion. Maintenance-free, moisture-resistant, and load-bearing — accommodates second floors and roof storage. Snap-in cover plates give a sleek look in controlled environments. Featured in pre-assembled guard shacks and exterior booths.

Alloy6063-T5 anodized LoadLoad-bearing Best forFDA food-processing · cleanroom labs · exterior booths FinishSatin anodized or painted

07 — Wall Panel Materials

Choose the panel by what it has to do.

Every InPlant wall panel is 3 inches thick, custom-fabricated, and built from an inner core sandwiched between outer surface materials. Cores are expanded polystyrene foam or rock wool for sound insulation. Surfaces are picked for environment — wash-down, weld-flash, sound attenuation, or aesthetics.

Built for outdoor pre-assembled booths — cement board laminated to foam, paired with anodized aluminum framing. Handles sun and driving rain.

½″ cement board

polystyrene core

½″ cement board

Custom paint or neutrals

Material VII

Soundstop™ NC

Robust gypsum shell with a rock-wool fill cavity. Wiring studs also rock-wool insulated; dual-pane windows; sealed insulated doors.

vinyl / FRP / steel face

gypsum

rock wool fill

gypsum

vinyl / FRP / steel face

Dual-pane windows & sealed doors

Material VIII

Specialty & Security

Slatwall for retail displays, dry-erase, cork board, PVC, custom laminates. Bullet- and blast-resistant available with integrated cameras & access control.

custom surface

polystyrene core

custom surface

Bullet- & blast-resistant available

A note on NC Construction

Noise Controlling and Non-Combustible. Two ½″ gypsum layers per panel contain or block sound. Windows come pre-framed with ¼″ tempered glass in standard or custom sizes. Doors are pre-hung 42″ × 7′ insulated steel with hinges, sweep, and key-in-lever lockset. Roll-up, sliding, and strip doors are available; conveyor and turntable openings can be designed in.

08 — From Order to Installed

~5 to 7 weeks. From the day you approve drawings.

Every project moves through the same four phases. InPlant's nationwide rep and dealer network handles project management, site visits, and oversight — Shelving Inc. is your point of contact through every step.

01Sketch & quote

Email a sketch. Get a call back.

Email a sketch, call to describe the project, or fill out the quote form. The local authorized dealer follows up — site visits are available, standard quotations return quickly with full descriptive detail and a written specification.

02CAD drawings

Detailed CAD comes back promptly.

After order placement, detailed CAD drawings come back for your approval. This is the moment to lock down door positions, window heights, paint colors, panel surfaces, and any equipment cutouts. Open inspections are welcome at any point.

03Factory build

4 to 6 weeks in Saint Louis.

Manufacturing in the climate-controlled St. Louis facility — strict in-house quality control from raw materials through assembly. Panels are painted in-factory. Everything ships on pallets via motor carrier with a complete packing inventory list.

Modular wall panels and components packaged for shipment on fork-pocketed pallets — *Plate 13 —* Packaged for motor freight.

04Site install

Forklift unloads. Walls go up.

A 3,000-pound capacity forklift with extended forks offloads. The nationwide dealer network's material-handling specialists handle assembly, or provide oversight as required. Installation runs alongside normal plant operation. Open inspections continue throughout.

Installation in progress — multi-story InPlant office structure being erected on a mezzanine above stadium seating — *Plate 14 —* Multi-story office under installation.

Start a project · 2026

Send us a sketch. We'll send back a CAD drawing.

Tell us what the room is for, the rough footprint, and any equipment that needs to live around or under it. We'll come back with a system spec, panel surface options, and an installed-by date — and the math on accelerated depreciation under IRS §179.

40ft

Max clear span

125psf

Roof load capacity

26ft

Max wall height

5–7wks

Quote to install

Request a Quote 1-800-637-9508

Shelving.com

InPlant Offices & Modular Buildings

A finished office,dropped into a working plant.