Floor Joists Capacity

So our house would look like the picture below with all floor joists 2 x 8.

Floor joists capacity.

Live load 30 lbs ft 2 1436 n m 2. In this case your joists are adequate to support a 30 psf live load and 10 psf dead load. With these factors the lightest joist will have a maximum span of 17 feet 8 inches. Location and configuration of heavy loads should be looked at on a case by case basis.

Floor joist capacities max working load 3 0 kn m 2 floor joist capacities for timber grade c 18 c 24 and c 30 joist center space ranging 300 to 600 mm are indicated in the diagram below. The floor joist spacing is the distance between the centers of any two installed joists. Span calculator for wood joists and rafters also available for the android os. In the example the joists have a spacing of 16 inches and a span of 11 feet 2 inches.

1 psf lb f ft 2 47 88 n m 2. For example a floor joist at 16 spacing s that can carry 53 pounds per linear foot would translate into a 318 pound single point load at its center. Bci joists are specially constructed floor i joists with flanges made from strong versa lam lvl. While most residential construction uses 2x8 joists with 16 inch spacing there are many other factors you need to consider when determining the proper joist span length.

You should check with your local building department for construction requirements in your area. 1 ft 0 3048 m. Since the example house we are designing for is 12 feet wide we need to find in the floor joist span table a joist size and centering that can span 12 or wider. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction.

Maximum floor joist span for no. Also available for the android os. This is the most common as the typical span is 15 feet. See the image below for an example of joists spaced 16 on center 16 o c.

The heaviest joist along with the above factors will span a maximum of 23 feet 8 inches. 1 in 25 4 mm. 2 grade of douglas fir are indicated below. Floor joist capacity max working load 3 0 kn m 2 as pdf file.

Bci joist span and size charts available for download. Reading the table you ll see that 2 x 8s installed 16 apart on center can span 12 4. Dead load weight of structure and fixed loads 10 lbs ft 2. The span table for a 30 psf live load 10psf dead load floor indicates a required fb value of 1 315 and a minimum e value of 1 800 000.