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Lumber — SPF 2x4 Stud Grade (Spruce-Pine-Fir)

Updated Mar 25, 2026
Standard dimensional lumber for wall framing. Actual dimensions 1.5 x 3.5 inches. Available in 8, 10, 12, 16 foot lengths. Stud grade meets IBC requirements for bearing walls up to 10 feet.

SPF (Spruce-Pine-Fir) is the most common framing lumber species group in North America. 2x4 stud grade is the workhorse of residential and light commercial wall framing. Design values: Fb (bending) 675 psi, Ft (tension) 350 psi, Fc (compression) 1150 psi, E (modulus) 1.2M psi per NDS. Moisture content: KD19 (kiln-dried to 19% max). Grade stamps: ALSC accredited agencies. Fire rating: unprotected wood has 0-hour rating. 1-hour rating achievable with 5/8 Type X gypsum each side. Spacing: 16 inches OC typical, 24 inches OC for some applications. Code reference: IBC 2308 for conventional light-frame construction.

TAGS
lumberwoodframing2x4spfstudcsi-06
DETAILS
csi division
06 - Wood, Plastics, Composites
environmental
{"renewable":true,"sustainability_grade":"A","embodied_carbon_kgco2_per_bf":-0.9}
material class
dimensional_lumber
cost benchmarks
[{"date":"2025-Q4","unit":"LF","region":"us_national","cost_low":0.45,"cost_mid":0.65,"cost_high":0.95}]
physical properties
{"e_psi":1200000,"fb_psi":675,"fc_psi":1150,"density_pcf":35,"fire_rating_hours":0}
applicable standards
["NDS","PS 20","IBC 2308"]
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