When to pool packs across work phases.
Should you round each work phase separately or combine an order?
Use the matching calculator
Use this decision sequence
- List the quantities needed in each phase before rounding.
- Check that every phase uses the same product, finish, lot requirements and pack basis.
- Calculate both separate-phase packs and pooled project packs.
- Check storage, shelf life and delivery timing with your supplier before choosing the pooled order.
Keep the quantities distinct
| Quantity or assumption | How to use it |
|---|---|
| Separate phases | Round every phase to a whole pack. |
| One compatible order | Add exact needs, then round once. |
| Different products | Keep their quantities and packs separate. |
Worked comparison
Two phases each need 12 units. A pack holds 10. Separate orders need 2 + 2 = 4 packs; pooling needs ceil(24/10) = 3 packs. The saving is one pack, with 6 units left after use. Ten illustrative components each need 0.03 m³. A selected bag yielding 0.025 m³ means two bags per isolated component, or 20 bags separately. Pooling the exact 0.3 m³ requirement produces ceil(0.3/0.025) = 12 bags. This difference is purchase rounding, not a change to the components’ geometric volume. Two illustrative finishes each need 3 m² and both come in 2 m² packs. Separate orders require two packs per finish, or four packs total. Pooling their 6 m² into three packs would leave one finish short if products cannot be substituted. The arithmetic saving is available only when the actual product and stock are compatible.
Check before using the estimate
Pooling incompatible products is a quantity error even if their pack sizes match.
All dimensions, product properties, prices and specifications in this example are illustrative arithmetic inputs. Use the values from your measured plan, selected product data sheet and supplier quote. This guide does not choose construction specifications or certify safety.
Calculation and scope checked 2026-10-04. Methods and scope.
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