How to use this tool
Enter each room's length and width in meters.
Add waste and coverage per pack, then check the rounded pack count and material cost before ordering.
Packs = ceil[sum(room areas) × (1+waste) / pack coverage]
Worked example
13 · packs
Fixed example using the settings below. Monetary examples use USD; dates and times use their stated reference values. This example stays unchanged when you edit your calculation.
Example inputs
- Room dimensions (m): length, width: 5,4; 3,2
- Waste allowance (%): 10
- Coverage per pack (m²): 2.2
- Price per pack: 35
Method illustration: A 20 m² room with 10% waste needs 22 m² of coverage.
Assumptions and limits
- Estimates material quantities only, not structural adequacy or code compliance. Verify measurements and manufacturer coverage/yield.
- Waste is added before rounding to whole packages. Material costs exclude delivery, labor and tax unless included in entered prices.
Check or report a result
Check the units, selected calculation and assumptions first. Compare the fixed example above with your inputs to identify what changed.
Report a calculation issue with the page address, hypothetical inputs, result displayed and result expected. Do not include passwords, bank details or other private information.