Exterior Siding Area and Panel Calculator
Calculate net facade area, installation allowance and whole siding panels after subtracting openings.
Formula
Planning estimate. Check product specifications and local requirements before purchasing.
Worked example: Siding Calculator
Measurements in this example
| Wall perimeter | 36 m |
|---|---|
| Height | 3 m |
| Openings area | 18 m² |
| Coverage per panel | 0.72 m² |
| Waste allowance | 10 % |
Calculated quantities
| Net cladding area | 90 m² |
|---|---|
| Area with allowance | 99 m² |
| Whole panels | 138 |
What to check
This calculation uses: Wall perimeter, Height, Openings area, Coverage per panel, Waste allowance. It returns: Net cladding area, Area with allowance, Whole panels.
Measure each face to the true edge and mark openings. Plan sheet orientation before deciding how much of an offcut can be reused.
Net surface with allowance is divided by the usable face area of one sheet or panel and rounded upward.
Check effective coverage after laps, tongues, starter profiles and corner details. Overall panel size may not equal installed coverage.
A total sheet count does not place joints. Framing layout, edge support, expansion gaps and fastening schedule remain essential.
Use the units beside each field. The values in the worked example are starting inputs; replace them with your measurements and the specifications of your material.
Compare alternatives
Open a tool, enter your measured dimensions, then save an estimate. Keep another version if you want to compare products or allowances.