Stock management is an integral part and major challenge of working with any kind of service dispatch company. Managers must ensure contractors have the right resources available at all times to best meet client needs, while equally minimizing overbuying to keep costs, risks and general operations lean, leaving contractors with little room for error while attending jobs.

When done well, lean stock management can offer many benefits to contractors. By keeping trucks stocked with only required supplies, operators can find items quicker, minimize waste and shrinkage and always make sure they have the right items needed for any given call out.

However, choosing to prioritize stock efficiency and lean management in an industry that can be unpredictable and involves hyper-specific parts may not always be optimal. There must be a better way for plumbing and hydronic contractors to manage truck stock without overbuying.

Truck Stock Challenges for Plumbing and Hydronic Contractors

For plumbing and hydronic contractors, commercial vehicles can act as small-scale warehouses designed to maximize efficiency by ensuring the right materials are available at the right times. 

However, stock management in an industry centered around frequent call outs and variable demands can be uniquely challenging. While some concepts can be carried over from wider industries, a truck cannot be managed in the same way as an industrial warehouse, exposing numerous significant stock challenges that plumbing and hydronic contractors must overcome.

Common stock challenges for plumbing and hydronic contractors can include:

• Carrying costs: Inventory carrying costs can range from 20% to 30% of total stock value across all industries, increasing the overall cost of running normal operations.

• Dead stock: Dead stock left over from previous overorders or inefficiently managed process adjustments can leave trucks overburdened with functionally obsolete items.

• Poor visibility: Unlike main warehouses, trucks are rarely monitored using real-time stock management systems, leaving contractors unaware of realistic inventory levels.

• Overstocking: Overstocking service vehicles can leave contractors with thousands in extra materials that slow vehicles and make it hard to find required parts efficiently. Keeping these costs under control is also an important part of financial best practice for small businesses. 

How Safety Stock Calculations Improve Inventory Management

To help address common stock challenges and ensure contractors have the right resources available to minimize first-time fix rate failures, leaders can borrow and appropriately adjust stock management practices from wider industries. Specifically, by performing safety stock calculations unique to service dispatch operations, teams can rescue the risk of overbuying.

What Is Safety Stock?

Safety stock is a warehouse inventory control term that refers to the reserve items sites keep on hand to minimize stockouts. Backed by site specific calculations, leaders determine how much extra stock is required at all times to meet needs and fulfil unpredictable demand spikes.

As plumbing and hydronic contractors are working with much smaller storage spaces and in an industry that can see large demand swings, safety stock calculations must be customized.

The below equation can be used to calculate optimal safety stock for service vehicles per item:

(max daily usage x max lead time) - (average daily usage x average lead time)

By applying this formula to high demand items like pumps, gaskets and ball valves, as well as low demand parts like LWCO sensors and high-limit aquastats, contractors can ensure their trucks have just enough inventory to address known needs and cover unforeseen swings in demand.

The Benefits of Calculating Safety Stock

By applying this inventory control principle to truck stock management, plumbing and hydronic contractors can more reliably ensure their vehicles have the right amount of resources at all times, as well as gain better visibility into stock levels throughout periods of variable demand.

Contractors who adopt safety stock calculations are often able to:

• Minimize emergency run-outs: Hydronic contractors can face significant demand spikes during sudden weather events like cold snaps and freezes. Safety stock offers a lean buffer against these events to reduce restocking and speed call out responses.

• Maximize on-task productivity: By calculating safety stock rather than overbuying based on guesswork, contractors can maximize on-site productivity and billable hours by ensuring the right parts are available for most jobs without overburdening vehicles. 

• Reduce issues with dead stock: Regular safety stock calculations provide plumbing and hydronic contractors consistent visibility into held and required inventory, this can help to reduce issues with dead stock over time by producing hard data to reference.

• Mitigate distributor lead times: Hydronic contractors often deal with hyper specific parts that can be hard to source efficiently with little notice; safety stock helps teams curb long lead times in the leanest possible way by stocking reserves based on data.

A Measured Approach to Stockout Mitigation

Maintaining efficient control over inventory is a top priority across all industries as businesses face rising supply chain, energy and labor costs. For plumbing and hydronic contractors, these issues can be exacerbated by industry-specific factors like demand for specialized parts, daily travel requirements, variable demand spikes and the low storage capacity of service vehicles.

To gain some of the protection against stockouts and first-time fix rate failures that overbuying can provide while minimizing the related risks of dead stock and bloated carrying costs, teams can adopt stock control practices from wider industries. By integrating safety stock calculations into existing workflows, smart contractors can take a measured approach to stockout mitigation.