Maximum Roof Span For 2x4

I used your formula backwards to calculate the max psf of a ceiling with 2x4 ceiling joists spanning 12 and spaced 24 o c.

Maximum roof span for 2x4.

1 ft 0 3048 m. Dead load weight of structure and fixed loads 15 lbs ft 2. Maximum and use lumber properties as follows. For light load roofs 24 o c.

Spacing your 2 4 shed rafters at 24 on center limits the width of your roof. 2 4 rafters can span up to 7. Assuming the fb of hemfir is maxxed at 1275 psi and i came up with 12 737 psf. Allowable spans for 2x4 top chord trusses using sheathing other than plywood e g.

Most roof framing is 24 on center and you can still build sheds up to 14 with 2 4 rafters at 24 on center. Spaced sheathing or 1x boards may be reduced slightly. Live load is weight of furniture wind snow and more. Douglas fir maximum horizontal roof rafter span for lumber grade selected structural and no.

While every effort has been made to insure the accuracy of the information presented and special effort has been made to assure that the information reflects the state of the art neither the west coast lumber inspection bureau the american wood council nor its members assume any responsibility for any particular design prepared from this online span calculator. Also available for the android os. Span calculator for wood joists and rafters also available for the android os. For heavy loads 2x4s can span up to 5.

Trusses must be designed for any special loading such as. 1 psf lb f ft 2 47 88 n m 2.