Skip to main content
Speclore

Floor Joists Span

Reference data and engineering information about floor joists span for building and construction applications.

floorjoistsspan

Overview

Engineering reference data for Floor Joists Span in building construction.

Key Formulas

U-value

U=1RtotalU = \frac{1}{R_{total}}

Overall heat transfer coefficient.

Heat Loss

Q=UAΔTQ = U A \Delta T

Heat transfer through building envelope.

Variables

Symbol Description Unit
UU U-value W/(m²·K)
AA Area m²
ΔT\Delta T Temperature difference K

Maximum Floor Joist Spans

The following tables provide maximum floor joist spans for No. 1 and No. 2 Grade Douglas fir lumber under specified live loads. Dead load is assumed to be 10 lbs/ft².

Unit Conversions

For reference, the following unit conversions are commonly used in structural engineering:

  • 1 psf (lbf/ft²) = 47.88 N/m²
  • 1 ft = 0.3048 m
  • 1 in = 25.4 mm

References