Strap (Cantilever) Footing Design Calculator

Design strap footings for exterior columns near property lines with strap beam, punching shear, and bearing checks

ACI 318-19DPT 1008-61Strap Beam DesignProperty Line Constraint

Note: This tool calculates per ACI/DPT standards but does not replace review by the design engineer.

Service (unfactored) loads. The exterior column is near the property line — the strap beam offsets the eccentricity.

Load P1 (kN)

Moment M1 (kN·m)

Column width (mm)

Column depth (mm)

Distance to property line (m)

From column center to the nearest property boundary

Load P2 (kN)

Moment M2 (kN·m)

Column width (mm)

Column depth (mm)

Bearing capacity: net allowable (kN/m²). Typical compacted soil: 150–300 kN/m².

Span between columns c/c (m)

Net allowable bearing capacity (kN/m²)

Soil density (kN/m³)

Footing depth below ground (m)

The strap beam connects the two footings. It must be stiff enough to keep soil pressure uniform. No soil bearing under strap.

Strap width

Strap depth

Concrete

Steel

Fill in column data and soil parameters, then click Calculate to design the strap footing