Attic Joists Live Load

A room used solely for sleeping might need to carry only 30 psf whereas a garage floor over a basement would need 50 psf or higher.

Attic joists live load.

In the case of 2x6 joists you can pair them up with additional 2x6 joists by nailing them together. Where they connect to both the top and bottom joists each gusset pair will transfer approximately 100 pounds that s 50 psf of floor load times the 3 foot gusset spacing times the 16 inch joist spacing divided by the two joists. Snow and wind loads. Strengthening attic joists for live loads by sistering.

An inaccessible attic space on the other hand might have a live load of only 20 psf. Use span tables for progressively heavier loads until you find the limits of your floor. If the attic joists are not adequate one way to strengthen the floor for live loads is to sister the old joists. There are also factors such as deflection elasticity and wood species that come in to play.

Sistering is the process of adding a new joist next to each existing joist. However if the attic is intended for storage the attic live load or some portion should also be considered for the design of. Consult local building codes for snow load capacity and reference the span tables for joists and rafters published by the american wood council awc. Use six 10d nails with plywood gussets or six 16d nails with 2x4s half into each 2x6 joist.

Attic ceiling joists with limited storage. 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. Live load psf dead load psf span calculator for wood joists and rafters available for the iphone. Loads should be determined in accordance with this chapter.

Standard joist spacing for the installation of attic flooring materials is 16 inches on center oc meaning the distance from the center of one joist to the center of the next joist is 16 inches. Span calculator for wood joists and rafters also available for the android os. Therefore if you have an attic space according to this scenario the ceiling joists can be designed for a live load of 10 pounds per square foot psf by using table r802 4 1.