Combine Compatible Material Orders

A material name is only the starting point

Two lines called paint or gravel are not necessarily one purchase. Compare the actual product or material specification, purchasing unit, package capacity and calculation parameters. Density, coverage and matching assumptions can affect what the quantities mean.

Keep source areas or rooms separate even when their purchasing requirement is grouped. A shared total should still be traceable to the measurements that produced it.

Add unrounded requirements on a compatible basis

Each source quantity should include its chosen allowance exactly once. Add compatible adjusted requirements, then perform the final whole-package rounding for the shared purchase. Do not add the allowance again at group level.

If units differ, a defined conversion may make the quantities comparable, but that alone does not establish that the materials or package specifications match. Preserve the original unit and parameter information rather than merging bare numbers.

Example: one order or two

Suppose two compatible concrete areas each require 0.11 m³ after their chosen allowance. With an illustrative yield of 0.012 m³ per bag, separate purchases each need 10 bags, for 20 bags in total.

A shared purchase first adds the requirements to 0.22 m³. Dividing by the same yield and rounding once gives 19 bags. The measured requirements have not changed; only the purchasing grouping has changed.

Resolve a conflict without discarding information

Different bag yields, carton coverages or product parameters should produce a clear conflict or separate lines. Review the two specifications and decide which is correct for the intended purchase. Do not silently overwrite one set of inputs or relabel incompatible packs as identical.

Wallpaper needs particular care: different effective strip lengths remain conservatively grouped and rounded separately. A common roll name does not create an optimised cutting plan.

Keep prices attached to their unit and currency

A price per bag is not a price per cubic metre. Enter the unit price for the actual purchasing unit and retain the currency. Missing prices should leave valid quantities intact. Different currencies must not become one unlabelled cost total without a supported conversion.

Before exporting, check each source appears once, all group specifications match, and the displayed count explains the whole packages you intend to buy. The shopping list records a plan; it does not submit an order to a supplier.

Frequently asked questions

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