THE NUMBERS, EXPLAINED
How to use this calculator.
Nested stepped terrain, each footprint covers its own elevation band starting at the previous contour. Every band rounds up to full sheet layers. Sheet count is aggregate area only, not a cutting layout.
Start with your inputs
Enter contour top elevations (mm), contour footprint areas (m²), foam sheet thickness (mm), purchased sheet area (m²). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Contour top elevations (mm) | 20,40,60 |
| Contour footprint areas (m²) | 2,1.5,1 |
| Foam sheet thickness (mm) | 20 |
| Purchased sheet area (m²) | 1 |
A worked example
With the example inputs above, layers in each elevation band is 1, 1, 1. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Layers in each elevation band | 1, 1, 1 |
| Total foam area (m²) | 4.5 |
| Minimum sheets by area | 5 |
How this is calculated
Layers in each elevation band
Divide each band rise by sheet thickness and round up.
Total foam area (m²)
Multiply layers in each band by its footprint area and add.
Minimum sheets by area
Divide aggregate foam area by sheet area and round up.
Symbols and units
- a
- Contour top elevations (mm)
- b
- Contour footprint areas (m²)
- c
- Foam sheet thickness (mm)
- d
- Purchased sheet area (m²)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Nested stepped terrain, each footprint covers its own elevation band starting at the previous contour. Every band rounds up to full sheet layers. Sheet count is aggregate area only, not a cutting layout.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Layers in each elevation band; Total foam area (m²); Minimum sheets by area. The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Nested stepped terrain, each footprint covers its own elevation band starting at the previous contour. Every band rounds up to full sheet layers. Sheet count is aggregate area only, not a cutting layout.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: Geometric formulas ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
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