Compare planned, ordered and used materials

Ordered minus used is a remaining quantity, not automatically waste. Keep returns, spare stock, breakages and unrecorded work separate.

Use one unit per line

Do not compare bags ordered with tonnes used unless you have a documented conversion for the exact product. Record planned buying quantity, the order delivered and the quantity actually used in matching units. Keep damaged deliveries and returns identifiable.

Worked example

A plan calls for 56 slabs, 60 are ordered and 55 are used. Ordered minus used is five slabs. Those five might be retained spares, returned stock, breakages or an incomplete count. Planned minus used is one slab; it answers a different question.

Close the material balance

Count remaining usable stock, returned material and documented losses. Check whether the supplied pack contained the assumed number and whether the completed footprint matches the plan. Do not infer an efficient installation solely from a low used quantity.

Keep the evidence modest

A single project can explain its own assumptions and outcomes, not establish a national waste benchmark. The Project 001 component is reserved for genuine owner-supplied records; no made-up site evidence is inserted here.

Planning guidance, not a quotation or a substitute for project-specific design and competent advice.