Fitting Booths Into Older Buildings

Working With Low Ceilings

Booths need height for the cabin, the intake plenum above it and sometimes an air make-up unit. In low buildings, options include booths with low-profile plenums, side-mounted or remote AMUs, or sidedraft or crossdraft designs that do not need a full ceiling plenum. Sometimes a pit or a lowered floor gains height for downdraft airflow. Check the clear height under trusses, lights, sprinkler lines and crane rails, not just the roof deck. Overhead cranes in older plants deserve special attention. A booth placed under a crane runway may block crane travel or limit hook height. Sometimes the booth can be located outside the crane bay, or the crane runway can be shortened, but those decisions affect plant operations and should be discussed with production teams.

• Measure clear height under the lowest obstruction
• Consider low-profile or side-mounted air handling
• Use crossdraft or sidedraft where height is tight
• Lowered floors can recover height in some cases

Column Spacing and Layout

Columns can limit booth width and length or interfere with doors and ductwork. Booths can sometimes be designed to fit between column lines, or columns can be enclosed within non-working areas of the booth. Moving or replacing columns is possible but expensive and requires structural engineering. Laying out the booth on accurate building drawings, with columns, doors and traffic paths, reveals options early. Old buildings often have additions built in different eras, with different column grids and ceiling heights. A booth that spans the joint between two sections can face mismatched floors, roofs and structures, so it is usually simpler to keep the booth within one section if the layout allows.

Roof Structure and Penetrations

Exhaust stacks, intake ducts and rooftop AMUs all affect the roof. Older roofs may lack capacity for added loads or may have deteriorated decking. A structural review identifies whether reinforcement is needed or whether equipment should go on the ground instead. Penetrations must be placed between structural members and flashed properly to keep the building dry. Roof condition around penetrations is a good time to plan repairs. Ground-mounted air make-up units and exhaust fans beside the building avoid many roof issues, but they need a level pad, protection from vehicles and a path for ducts through the wall. Wall penetrations in older masonry or metal siding should be reinforced and sealed to prevent leaks and air infiltration.

• Structural review before adding rooftop loads
• Place penetrations between joists or purlins
• Consider ground-mounted equipment if the roof is limited
• Repair roofing around new penetrations

Old Electrical Service and Utilities

Booth fans, lighting, heaters, controls and compressors add electrical load. Older buildings may have limited service capacity, outdated panels or wiring not suited to the booth's needs. An electrical assessment early in the project reveals whether a service upgrade is needed, which can take time to coordinate with the utility. Gas service and compressed air capacity should be checked at the same time. Older wiring may not meet current requirements for hazardous locations near spray areas. Plan to run new wiring to the booth and its controls instead of reusing existing circuits, and check grounding throughout the area. Lighting circuits and fixtures in the booth area typically need to be replaced to match the booth requirements.

Creative Layouts That Work

Sometimes the best solution is unconventional: placing the booth along an exterior wall to simplify exhaust, using a crossdraft booth with wall exhaust, splitting operations into a smaller booth plus a separate prep area, or building a booth room using existing walls with booth components added. Each option has tradeoffs in airflow, cost and code requirements. Discuss options with the installer and the authority having jurisdiction before committing. Older buildings sometimes come with hidden surprises: undocumented utilities in walls, old pits under floor plates, or deteriorated structural members. Allow time in the schedule for investigation and adjustments. A thorough site survey before the design is finalized reduces those surprises and makes it easier to price the work accurately.