Douglas Fir, Hem-Fir & SPF Deck Joist Span
AWC DCA 6 groups Douglas Fir-Larch, Hem-Fir, and Spruce-Pine-Fir together. Incising is assumed. Use this page when your stamp matches that group.
DF-L / Hem-Fir / SPF — full Table 2 slice
Reading this species group
At 16″ o.c., Table 2 lists 2x8 = 11'-1", 2x10 = 13'-7", and 2x12 = 15'-9" for this group. Those are shorter than Southern Pine at the same cells (11'-10", 14'-0", 16'-6") and longer than the Redwood / Western Cedars group (10'-7", 13'-0", 15'-1"). Compare on Southern Pine and Redwood / cedar.
DCA 6 footnotes assume incising for DF-L, Hem-Fir, and SPF. If your stock is not incised, do not “upgrade” the numbers—stay with the published table or get an engineered value. Wet-service and No. 2 grade assumptions still apply; details on assumptions.
Common combo pages: 2x8 @ 16″ o.c., 2x10 @ 16″ o.c.. Need a target length? Try joist size for a 12-foot span (filter only—no invented spans).
FAQ
Is Hem-Fir the same row as Douglas Fir-Larch?
In DCA 6 Table 2, yes—one combined species group. Your grade stamp still matters for procurement and treatment.
Where is the calculator?
Home deck joist span tool or dedicated calculator page—both load the same JSON.