How do you calculate measured snow load?
Convert verified roof snow pressure, snow depth and density, or snow-water equivalent into areal mass and total load over horizontal area. Measured-load arithmetic only, not code design load or roof capacity. No ground-to-roof, drifting, thermal, exposure, slope or load-combination factors are inferred. This result cannot establish roof safety.
Which measurements should you enter?
Use horizontal projected area, not the sloped surface area of the roof. Density and depth must represent the same snow condition.
Which equation gives the result?
Snow mass per horizontal area = depth × verified snow density, or snow-water depth × 1,000 kg/m³; force pressure = areal mass × 9.80665; total force = uniform pressure × area + specified extra zone pressure × zone area
What does a worked example show?
Snow 0.2 m deep at a measured density of 200 kg per cubic meter weighs 40 kg per square meter. Across 100 square meters, its force is approximately 39.23 kN.
Which assumptions affect the estimate?
Snow water equivalent already represents the water mass in the snowpack. Do not multiply it by snow density again.
What should you verify before using the result?
An additional local pressure applies only to its entered zone. This arithmetic does not determine structural capacity, safe access, ground-to-roof code factors or drift design.
How do you keep units consistent?
Select measurement units before entering dimensions. Keep density, price and product coverage units attached to their labels. The calculator converts geometry but does not invent a missing supplier value.
Which input units apply to this worksheet?
The table lists the field units and the condition in which each input is used.
| Input | Units | Condition |
|---|---|---|
| Horizontal projected loaded area | ft² / m² | all modes |
| Measured snow depth normal to horizontal area | in / cm | method:depth |
| Verified snow density (kg/m³) | as labeled | method:depth |
| Measured snow-water equivalent depth | in / cm | method:swe |
| Verified uniform roof snow pressure | as labeled | method:pressure |
| Area with additional local snow load (optional) | ft² / m² | all modes |
| Verified additional local snow pressure (optional) | as labeled | all modes |
How can you compare and save scenarios?
Calculate a baseline, add it to comparison and change one project value. Copy or share the result, download the order sheet or print inputs and results. Reload and clear controls return the worksheet to blank numeric inputs.
Which tools help with the next calculation?
Continue with Roofing Calculator and Roof Pitch Calculator. Check scope and units before transferring the result.
