Dimension lumber (2" to 4")

3x8

Standard: DOC PS 20 / NDS SupplementSource: Nominal → actual dry sizes (PS 20), calculated
xyb = 2.5d = 7.25
Cross-section, to scaledimensions in inches

Dimensions

Depthd
7.25in
Widthb
2.5in

Mass and area

Cross-sectional areaA
18.12in²
Outside perimeterP
19.5in

Strong axis x–x

Moment of inertiaIx
79.39in⁴
Elastic section modulusSx
21.9in³
Plastic section modulusZx
32.85in³
Radius of gyrationrx
2.093in

Weak axis y–y

Moment of inertiaIy
9.44in⁴
Elastic section modulusSy
7.552in³
Plastic section modulusZy
11.33in³
Radius of gyrationry
0.7217in

Torsion and stability

Torsional constantJ
29.57in⁴

Equivalents in other standards