Worked exampleExported from Calvance
Aquarium Water & Bucket Fills
Estimate rectangular aquarium water volume, choose a water-change share and work out how many bucket fills to prepare.
View template and methodWallpaper Rolls & Material Cost
Work out full-height strips, whole rolls and material cost for one wall using wallpaper that needs no pattern matching.
Worked exampleExported from Calvance
Exported by the iOS App After importing, edit the numbers in Calvance.
When to use it
Use this before ordering wallpaper for one rectangular wall without openings. The example uses metres and a 0.53 m × 10 m roll; enter the actual usable width and length of your product. This example uses simulated USD prices, not current market quotes.
Inputs
USD
| Inputs | Default |
|---|---|
| Wall width (m) | 4.8 |
| Roll width (m) | 0.53 |
| Roll length (m) | 10 |
| Wall height (m) | 3 |
| Total trim (m) | 0.2 |
| Roll price (USD) | 40 |
Calculation method
Round wall width ÷ roll width up to whole strips. Round roll length ÷ (wall height + total top-and-bottom trim) down to strips per roll. Round required strips ÷ strips per roll up to whole rolls, then multiply by the roll price.
ceil(4.8 [Wall width m]/0.53 [Roll width m]) → Strips needed
floor(10 [Roll length m]/(3 [Wall height m] + 0.2 [Total trim m])) → Strips per roll
ceil(Strips needed/Strips per roll) → Whole rolls
Whole rolls × 40 [Roll price USD] → Material cost USD
Change one input
Change wall height from 3 to 3.2 m. Required strips stay at 10, but each roll yields 2 instead of 3 strips, so the order rises from 4 to 5 rolls.
| Result | Default | Changed |
|---|---|---|
| Strips needed | 10 | 10 |
| Strips per roll | 3 | 2 |
| Whole rolls | 4 | 5 |
| Material cost (USD) | 160 | 200 |
Results are displayed to at most two decimal places; later formulas use unrounded values.
Scope and limits
- No pattern matching; one wall without openings.
- Trim includes both ends. Offcuts are not joined.
- Material cost only; no labour, adhesive or delivery.
All dimensions must be positive; trim and price may be zero. Each roll must yield at least one full strip. Do not subtract doors or windows or reuse short offcuts in this model. No automatic spare-roll allowance is included.
Download and import into Calvance to edit the numbers. The canvas does not reject every invalid input; check the stated ranges.
Common questions
Can I divide wall area by roll area?
Not reliably here: short offcuts cannot form a full-height strip. Whole-strip cutting can require more rolls than an area-only estimate.
How to import your template
We recommend using the latest version of Calvance.
- Save the file. Choose Download template and save the .calvx file to Files on your iPhone or iPad. From a computer, you can send it to your device with AirDrop.
- Open Import. In All Canvases in Calvance, tap the add button to open the template screen, then choose Import.
- Choose the file. Select the saved .calvx file to create your own canvas. Importing uses one canvas from your allowance.
- Edit and check. Check the results against the worked example, then add your numbers. Duplicate the canvas to keep different versions.
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Worked exampleExported from Calvance
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View template and methodWorked exampleExported from Calvance
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Separate canvases.
Choose a plan when you need more canvases, high-resolution image exports, or sync across devices.