Forklift Aisle Requirements – A Guide for Best Warehouse Layouts

Here is the forklift aisle requirements guide for various types of forklifts. Please note that “clear aisles” refers to the space between products (pallets) stored in the aisle. This dimension is generally 6 inches narrower than the “rack to rack” or “steel to steel” aisle dimensions. If pallets overhang the pallet racking by 3 inches on each side, the rack is set 6 inches further back.

Forklift Aisle Requirements Guide

NOTE: This forklift aisle requirements information is provided as a rough guide only. When designing a warehouse or pallet rack layout, consult with the lift truck manufacturer to ensure the right angle stacking aisle requirement is met, avoiding costly mistakes.

Wide Aisles – Counterbalanced Forklifts

Wide aisles are typically used for counterbalanced lift trucks. The general rule of thumb for sizing a lift truck, such as a sit-down 4-wheel or 3-wheel forklift, is:

Head Length of the Lift Truck + Length of Load + 12″ for Maneuverability + 6″ Pallet Overhang

Head length: This is the distance from the back of the forklift to the front of the load backrest.

Load length: This refers to the length of the pallet along the stringer (the long 2″x4″ that runs the length of the pallet) plus any product overhang.

Keep in mind that pallets typically sit on a beam and overhang by 3″ (for a 48″ pallet).

4-Wheel Counterbalanced Forklift Aisles

4-wheel counterbalanced trucks typically require aisles sized between 12 and 14 feet.

3-Wheel Counterbalanced Forklift Aisles

Many warehouses use aisles between 11 and 12 feet for 3-wheel counterbalanced lift trucks.

Stand-up Counterbalanced Forklifts

For this type of forklift, aisles between 10.5 and 11.5 feet are usually adequate.

Narrow Aisles – Forklift Aisle Requirements for Reach Trucks

Narrow aisles typically accommodate Reach Trucks and Deep Reach Trucks. Narrow aisles are generally around 9 feet wide, but it's essential to size the aisle for both storage and productivity.

For example, the aisles at Home Depot are about 8.5 feet, which is narrower than most warehouses. However, Home Depot prioritizes storage over efficiency, so their setup may not suit your operation. It is highly recommended to consult a warehouse design expert to ensure your dimensions are optimized for your equipment and usage.

Reach Truck

Many warehouses use a 9.5-foot aisle with an extra 6 inches for pallet overhang, making the total space between racks 10 feet. When using a Reach Truck, proper handling is essential. The length of a Reach Truck with a 48-inch pallet is about 104 inches. While it may seem tight in a 108-inch aisle, if the truck is driven as designed, a 9-foot aisle will suffice.

How to Drive a Reach Truck

To effectively operate a Reach Truck in a narrow aisle, approach the racking with the inside base leg (outrigger) 8 inches from the pallet rack column. Line up the load wheel with the upright column, then turn the steering wheel 90 degrees. This will pivot the truck into place, allowing you to extend the pantograph (scissor mechanism) and deposit the pallet.

Reach Truck Aisles

For Reach Trucks, use 9 to 9.5-foot aisles, adding 6 inches for pallet overhang (3 inches on each side). (For more details, see Reach Trucks Explained.)

Deep Reach Truck

For Deep Reach Trucks, add 12 to 18 inches more to the aisle size. These trucks are longer due to the extended scissor mechanism and heavier capacity, requiring aisles between 10 and 11 feet wide.

Very Narrow Aisles (VNA)

Very Narrow Aisles are defined as aisles narrower than the typical 9-foot aisle for Reach Trucks. Turret trucks can operate in aisles 30% to 40% narrower than Reach Trucks, though the cost of these trucks can be double.

Very Narrow Aisles are usually guided. Operating VNA trucks in unguided aisles can reduce productivity and increase the risk of rack and product damage due to poor visibility from steep angles.

Turret Truck / Swing Reach

A Turret Truck typically requires aisles 10 to 18 inches wider than the lift truck (assuming a 48″ x 40″ pallet). Clear aisles can be as narrow as 66 inches (5.5 feet), while rack-to-rack dimensions require 72-inch aisles (due to pallet overhang).

Order Picker / Stock Picker

A free-wheeling cherry picker or order picker requires 18 inches of clearance on either side in unguided aisles. A guided order picker can operate with just 6 inches of clearance on each side.

Order pickers are typically the width of a pallet (40 inches), so:

• Unguided Cherry Picker aisle: 76 inches
• Guided Cherry Picker aisle: 52 inches
• In a Turret Truck Aisle: 72 inches, though a wider platform is needed for the picker.

Note: Always consult your lift truck manufacturer before anchoring pallet racks. Forklift aisle requirements can change with new models. Pallet rack installation should be handled by professionals to ensure compliance with local building codes. Consult a licensed local pallet rack installation company to ensure your setup meets safety and code requirements.