The number of pallets a refrigerated "reefer" can hold depends primarily on whether it is a road-going trailer or an ocean shipping container, as well as the loading configuration used.
Refrigerated Trailers (Road Transport)
Reefer trailers in North America typically follow standard sizes similar to dry vans, though insulation may slightly reduce interior space.
- 53-Foot Trailer:
- Single-stacked: Typically holds 26 standard (48" x 40") pallets in a straight side-by-side pattern.
- Maximized Capacity: Using a "pinwheel" pattern (alternating orientations), a skillful loader can fit 28–30 pallets.
- Double-stacked: Can hold up to 52 pallets if the cargo is stackable.
- 48-Foot Trailer:
- Single-stacked: Fits 24 pallets.
- Double-stacked: Can hold up to 48 pallets.
- 26-Foot Box Truck:
- Single-stacked: Fits 12–14 pallets.
- Double-stacked: Fits up to 28 pallets.
Refrigerated Shipping Containers (Ocean Freight)
Ocean reefers have smaller internal dimensions than road trailers due to heavy insulation and the front-mounted refrigeration motor.
- 40-Foot Reefer: Generally holds 20–21 standard pallets in a single layer.
- 20-Foot Reefer: Generally holds 8–10 standard pallets.
- 48-Foot Container (Intermodal): Can hold 24 pallets single-stacked or up to 48 with vertical load bars.
Key Considerations for Capacity
- Stacking Limitations: Reefers often have lower internal height clearances due to overhead air chutes and ceiling ductwork. If double-stacked pallets are nearly touching the ceiling in a dry van, they likely will not fit in a reefer.
- Airflow Requirements: For temperature-controlled cargo, you must leave room for air to circulate (often through T-rail floors or below air chutes). Overpacking to the absolute maximum can compromise cooling efficiency.
- Weight Limits: Refrigerated units are heavier (higher tare weight) than dry vans, which can reduce the maximum allowable payload weight even if there is physical space for more pallets.