Roof Truss Quantity Calculator
Estimate roof truss positions, extra trusses, layout spaces, actual spacing, roof plan area and preliminary material and installation cost.
Default project preview
24 trusses
Layout positions
22
Layout spaces
21
Actual average spacing
22.9 in
Roof plan area
1,344 ft²
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Layout spaces = round up (building length ÷ truss spacing). Layout positions = spaces + 1. Total trusses add the entered extra quantity.
FAQ
Roof Truss Quantity Calculator questions
Why is the position count one more than the spaces?+
A row of spaces has a truss at both ends, so twenty spaces require twenty-one positions.
Does the calculator design a truss?+
No. Truss geometry and member design must come from an engineer or truss manufacturer.
Should gable-end frames be counted?+
The layout positions include both ends. Confirm whether the supplier provides standard trusses, gable frames or special end assemblies.