Warehouse Layout

Layout of a warehouse depends on the proposed material handling system and requires development of a floor plan to facilitate product flow. It is difficult to generalize about warehouse layouts since they must be refined to fit specific needs. The following considerations determine the location of a warehouse

• Market service area and cost of distribution from the warehouse to the market service area.
• Transport requirements and facilities available in the form of rail, link roads and road vehicles.
• Transportation rates prevailing in the area and distribution costs per unit are low.
• Competition by rival companies and whether they have warehouse in the same area.
• Availability of power, water, gas sewage disposal and their cost.
• Labour supply and labour costs in the area.
• Industrial relations climate and labour productivity.
• Pricing arrangements and the level of service desired to be rendered in terms of availability of the product to the customer.
• Individual company requirements and constraints.
• Real estate, excise and government taxes assessed in the area.
• Attitudes of local residents and government towards establishment of the warehouse.
• Restrictions associated with warehouses.
• Potential for later expansion.
• Cost of land for the warehouse and other costs.
• Possibility of change in the use of the facility at a later date if the company so desires, and lease or sale of the land and buildings.

Pallet Size

If pallets are to be utilized, the first step is to determine the pallet size. A pallet of nonstandard size may be desirable for specialized products, but whenever possible, standardized pallets should be used because of their lower cost. The second step in planning a layout involves the pallet positioning. The basic method of positioning pallets in a mechanized warehouse is a ninety-degree, or square, placement. Square placement means that the pallet is positioned perpendicular to the aisle. The square method is widely used because of layout ease.

Pilferage Protection

Protection against theft or any harm is required as a result of the increased vulnerability of firms to riots and civil disturbances. All normal precautions employed throughout the enterprise should be strictly enforced at each warehouse.

As standard procedure, only authorized personnel should be permitted into the facility and surrounding grounds and entry to the warehouse yard should be controlled through a single gate. Without exception, no private automobile-regardless of management rank or customer status-should be allowed to penetrate the yard adjacent to the warehouse. Computerized inventory control and order processing systems help protect merchandise from being carried out of the warehouse doors. No items should be released from the warehouse unless accompanied by a computer release document. If samples are authorized for use by salespersons, the merchandise should be separate from other inventory.

Numerous instances have been discovered where organized efforts between warehouse personnel and truck drivers resulted in deliberate over-picking or high-for-low-value product substitution in order to move unauthorized merchandise out of the warehouse. Employee rotation, total case counts, and occasional complete line-item checks can reduce vulnerability to such collaboration.

Product Deterioration

Within the warehouse, a number of factors can reduce a product or material to a non-usable or non-marketable state. The most obvious form of product deterioration is damage from careless transfer or storage. Another major form of deterioration is non-compatibility of products stored in the same facility. The primary concern is deterioration that results from improper warehouse work procedures. A constant concern is the carelessness of warehouse employees. Regardless of how often operators are warned against carrying overloads, some still attempt such shortcuts when not properly supervised. Thus keeping all these factors in mind, the final warehouse design and layout should be finalized.

Layout Basics

The receiving of goods on to the warehouse site begins at the gatehouse. The layout thus needs to include all the external areas within the perimeter fence, such as

Vehicle roadways – Roadway markings and signage are essential. The vehicle flow may be one-way around the site or two-way to and from the loading bays. In the latter case, access still needs to be provided for emergency vehicles, such as fi re tenders, to all sides of the building. In the case of one-way flows, a clockwise direction may be better for right-hand-drive vehicles to allow drivers to reverse a trailer on to a bay more easily, whereas anticlockwise is more suitable where left -hand-drive vehicles are the norm.

Parking areas – Adequate vehicle, trailer and swap-body parking needs to be provided. Power points may be needed where temperature-controlled units are to be parked. The car park for staff and visitors should be separated from the heavy goods vehicle areas for safety reasons, as well as for security reasons (ie keeping cars away from direct access to the warehouse).

Ancillary areas – Many such areas may be needed, for example fuel points, vehicle washing facilities, weighbridge, generators, empty unit load area, waste compactors, sprinkler tanks and fi re assembly points. In addition, landscaping to shield the warehouse and vehicles from the local environment may be required. The unloading and loading bays may be at opposite ends of the building, to enable a through flow of goods, or may be adjacent to each other on the same side of the building, to enable a U-flow. Other options include an L-flow, or some mix of these.

A through-flow may offer a better flow of goods within the warehouse itself, although in practice, with goods moving from receiving to reserve storage and then to picking, sortation, packing and dispatch, it is not always the case that this flow is any better than a U-flow.

Through-flow is oft en used when the number of unloading and loading bays required is too great to fi t on one side of a building, as in a warehouse handling a rapid turnover of goods. A through-flow layout is also particularly suited to a cross-dock warehouse, such as a parcel sortation centre, where a long thin building may be appropriate, with incoming vehicles along one of the long sides and outgoing vehicles on the opposite side. However, in an inventory-holding warehouse, a U-flow may be more suitable for cross-docking, as the distance that the goods need to travel will be far less than with though-flow.

The actual vehicle bays themselves may be

• Level intake – This is where the warehouse floor is at the same level as the external roadway. It is suitable for the side-unloading of vehicles by lift truck. Vehicles may be unloaded outside (eg under a canopy) or brought into the building, although, with the latter option, care must be taken with fume extraction and maintaining the required temperature in the warehouse.
• Raised dock – With a raised dock, the warehouse floor is at the same level as the bed of the vehicle, so that a pallet truck or lift truck can drive directly on to the vehicle by means of a dock leveller. This is normal in the case of end-unloading (eg of box vans or containers). Raised docks are normally at 90 degrees to the building, but may also be set out in a ‘saw tooth’ or ‘finger’ configuration. In the latter instance, side-unloading may also be possible.