Living Roof (Earthen) Calculator

Soil depth and plant selection for earthen roof systems.

Roof area (sq ft)

Soil depth (in)

Drainage layer (in)

Roof slope %

Tab to move between fields

Soil (cu yd)

5.56

Drainage gravel (cu yd)1.85

Saturated load (psf)60

Membrane (sq ft)360

How to Use This Calculator

Enter Roof Area (sq ft) and the planned Soil Depth (inches) for your growing medium.
Set Drainage Layer Depth (in) and Roof Slope % to determine drainage requirements.
Review Soil Needed (cu yd) and Drainage Gravel (cu yd) to plan material delivery.
Check Saturated Load (psf) — verify this against your roof structural capacity before proceeding.
Consult a structural engineer if the saturated load exceeds the roof's design load.

How the result changes with Roof area (sq ft)

Roof area (sq ft): Total area of the living roof.
Soil depth (in): Depth of growing medium (4-6 in extensive, 8-24 in intensive).
Drainage layer (in): Thickness of gravel drainage layer below soil.
Roof slope %: Roof pitch as a percentage (2% minimum recommended).

Identify Input Parameters
4 parameters
Roof area (sq ft) = 300, Soil depth (in) = 6, Drainage layer (in) = 2, Roof slope % = 2 = 4 input(s) provided
Calculate Soil
Soil = round(soilVolCuFt / 27 * 100) / 100
5.56 = 5.56
Calculate Drainage gravel
Drainage gravel = round(drainVolCuFt / 27 * 100) / 100
1.85 = 1.85
Calculate Saturated load
Saturated load = round(saturatedWeightLb / roofAreaSqFt * 100) / 100
60 = 60