IceBossPro Blog — Ice Delivery Scheduling

Par-Driven Scheduling in Ice Delivery Software

Most scheduling is calendar-first: pick a day, repeat it, hope the quantity is close. Par-driven scheduling flips that around. It starts with the freezer — how much ice an account should have and how fast it disappears — and lets those facts decide both when the next visit happens and how much you drop when you get there. It is the single feature that separates guessing from knowing, and it is the reason a well-run ice delivery scheduling software platform can keep fifty freezers full without anyone doing arithmetic on a clipboard.

The two numbers that drive everything

Par-driven scheduling rests on two numbers per location. The first is the par-level — the amount of ice you want present in that freezer or merchandiser right after a restock. Think of it as the "full" line. The second is the burn rate — how many bags that account goes through per day. Par-level is something you set with the customer based on their storage; burn rate is something the software learns by watching how much you actually drop and how long it lasts between visits. Once the system knows both, it can answer the only two questions that matter on an ice route: when does this account need me, and how much do I bring?

The restock quantity math

The quantity math is simple enough to trust and precise enough to matter. When you arrive, the freezer holds some remaining amount below par. The restock quantity is the par-level minus what is left — the amount needed to bring it back to full. If par is sixty bags and the driver finds twelve on hand, the drop is forty-eight. Par-driven software either calculates that from a driver-entered on-hand count or estimates it from the burn rate and days elapsed since the last visit. Either way, the driver is not eyeballing it and the office is not guessing. You bring what the freezer needs to reach par, no more piling up product the customer cannot store, no less leaving them short before the next cycle.

How par-levels set frequency

The elegant part is that the same two numbers also decide timing. Divide the usable capacity — par-level minus a safety floor you never want to drop below — by the daily burn rate, and you get the number of days a full freezer lasts. A sixty-bag par with a ten-bag safety floor and a burn rate of ten bags a day gives you five days of runway, so the account wants a visit roughly every five days. Par-driven scheduling does that division for every location and places the next visit before the freezer would hit its floor. Frequency stops being a fixed "every Tuesday" guess and becomes a calculated consequence of how the account actually consumes ice.

Why fixed frequency fails and par-driven wins

A fixed weekly schedule is wrong most of the year. In a fixed model, an account that empties in four days during a heat wave still waits the full seven and runs dry for three of them, while the same account in the shoulder season gets a visit it did not need, wasting a stop and stranding product it cannot fit. Par-driven scheduling closes both gaps automatically. When the burn rate climbs, the runway shrinks and the next visit pulls forward. When demand cools, the runway stretches and the software backs the visit off. You are always arriving near the moment the account genuinely needs you — not too early, not too late.

Learning the burn rate over time

Nobody knows a new account's burn rate on day one, and par-driven software does not pretend to. It starts with your best estimate and then sharpens it every cycle. If the freezer is nearly empty when you arrive, the account is burning faster than assumed and the system revises the rate up, tightening future frequency. If there is still plenty on hand, it eases the rate down. After a few visits the number settles into something accurate, and the schedule quietly tunes itself around each location's real behavior. This is why par-driven scheduling gets better the longer you run it — the data compounds.

Seasonal par and burn shifts

Ice is a seasonal business, and par-driven scheduling absorbs the swing without a manual overhaul. You do not have to rebuild your calendar every May and October. As burn rates rise into summer, frequencies tighten and drop quantities grow across the whole book at once; as they fall into winter, the schedule relaxes just as automatically. For accounts with dramatic swings — a seasonal stand, a summer-only tourist stop — you can adjust the par-level itself or place a hold, and the math re-flows from there.

Par-driven scheduling and capacity

Because every par-driven visit carries a calculated restock quantity, those numbers roll straight into capacity planning. The software already knows how many bags each stop will take, so it can total a route day's volume and warn you before a truck is overbooked. Par logic and capacity planning are two halves of the same engine: par decides the per-stop quantity, and capacity adds those quantities up against the truck. For more, see Ice Scheduling Software vs Generic Calendar Apps.

IceBossPro was built by people who have knelt in front of a lot of freezers doing this math by hand, and par-driven scheduling is that math made automatic. Set the par, let the system learn the burn rate, and the software delivers the right amount at the right time to every account — cycle after cycle, season after season.