Dimension lumber (2" to 4")

4x8

Standard: DOC PS 20 / NDS SupplementSource: Nominal → actual dry sizes (PS 20), calculated
xyb = 3.5d = 7.25
Cross-section, to scaledimensions in inches

Dimensions

Depthd
7.25in
Widthb
3.5in

Mass and area

Cross-sectional areaA
25.37in²
Outside perimeterP
21.5in

Strong axis x–x

Moment of inertiaIx
111.1in⁴
Elastic section modulusSx
30.66in³
Plastic section modulusZx
45.99in³
Radius of gyrationrx
2.093in

Weak axis y–y

Moment of inertiaIy
25.9in⁴
Elastic section modulusSy
14.8in³
Plastic section modulusZy
22.2in³
Radius of gyrationry
1.01in

Torsion and stability

Torsional constantJ
72.24in⁴

Equivalents in other standards