Warehouse performance is shaped long before the first pallet is stored. It is influenced by layout choices, process design, data quality and how well space and operations evolve together over time.

Many warehouses experience growing pressure on throughput, longer walking distances and increasing operational complexity. In some cases, efficiency improvements within the existing footprint create immediate relief. In others, growth ambitions call for expansion or an entirely new site. In both situations, the same question applies: how do you ensure that every square metre, current or future, delivers maximum operational value?

In this WDP Brain Session, warehouse optimisation expert Dave Van Casteren (DCwise) shared practical principles to improve efficiency, accuracy and flow in warehouse operations. These principles help organisations get more out of today’s warehouse, while also laying a solid foundation for future growth.

This article summarises the key insights from the webinar ​“Warehouse optimisation: gaining time and space”

When warehouse performance comes under pressure, the cause is rarely a single bottleneck. Efficiency typically erodes gradually:

• fast movers drift to less suitable locations
• layouts no longer reflect current volumes or order profiles
• walking paths grow longer and inconsistent
• master data no longer matches reality

Individually, these issues seem manageable. Combined, they reduce throughput, increase handling effort and limit how effectively space is used.

The webinar made one thing clear. Sustainable performance starts with strong fundamentals

1. Pareto analysis and the golden zone

In almost every warehouse, a limited share of SKUs generates most picking activity. A Pareto analysis identifies these fast movers, the A‑items.

The golden zone principle focuses on locations between knee and shoulder height. These are the safest and fastest pick locations. Placing A‑items here leads to:

• faster picking
• lower physical strain
• fewer errors

Typical actions include classifying SKUs in the WMS, defining the golden zone per area and reserving these locations for A‑items.

2. Location occupancy: the right space for the right goods

Efficient warehouses maintain sufficient usable locations per zone and per location type.

When this balance is lost, goods end up temporarily stored in aisles or placed in incorrect locations. Practical improvements include:

• relocating slow-moving items
• moving reserve stock away from prime areas
• consolidating SKUs spread across multiple locations
• reserving buffers for inbound and replenishment

These measures improve flow and reduce unnecessary handling..

3. Walking paths: reducing wasted movement

In manual picking environments, walking distance directly affects productivity.

Without a clear routing logic, pickers develop their own paths, increasing travel time and variability. Defining pick paths and embedding them in WMS routing reduces distance without increasing pressure on people. Testing planned routes against real orders helps fine-tune performance.

4. Layout as a driver of flow

A well-structured warehouse layout groups products logically, based on speed, size, weight and outbound flow.

When different product types are mixed without structure, efficiency suffers. Clear zoning, supported by WMS coding, improves flow and simplifies daily operations.

5. Slotting: matching location size to demand

Slotting defines the optimal zone and location size per SKU, based on physical characteristics and sales data.

Frequent replenishments, empty pick locations or fast movers in poor positions indicate lost efficiency. Calculating ideal slot sizes and monitoring deviations helps maintain consistent performance over time.

These five principles are dynamic. Without follow-up, even strong improvements fade.

Efficiency typically declines when master data becomes outdated, checks are manual and deviations remain invisible. Without structure, performance gradually slips, often unnoticed.

Reliable master data is the foundation of efficient operations. SKU dimensions, location data and sales history must reflect reality and be actively maintained.

To support this, the webinar introduced the concept of a storage control tower. This lightweight layer on top of the WMS monitors the five principles, highlights deviations and translates them into concrete improvement actions.

Optimising improves performance today. Controlling ensures it stays consistent tomorrow..

Efficient warehouses do not happen by accident. They are the result of deliberate choices, continuous optimisation and a clear long-term vision.

At WDP, we look at warehouses end to end: from operational efficiency and process optimisation to real estate strategy, expansion and development. By combining operational insight with real estate expertise, we help organisations make informed decisions about how to optimise today and how to grow tomorrow.

Whether the next step is improving flow within an existing site or preparing for expansion, efficiency is what ensures that every investment delivers lasting value.

Want to see how these principles work in practice, with concrete examples and visuals?

You can rewatch the full WDP Brain Session ​“Warehouse optimisation: gaining time and space” on demand held in collaboration with Dave van Casteren, Logistics Expert, Project and Program Manager and 6 Sigma Black Belt at DCwise.

About DCwise
DCwise is an independent logistics consulting firm specialising in warehousing and intralogistics.
We support organisations in optimising, designing and digitising their end-to-end logistics operations.
By combining deep hands-on warehouse expertise with strong system and IT know-how, we deliver solutions that work not only in theory, but also create sustainable value in day-to-day operations. DCwise