Floor Joist Blocking Requirements

To transfer load from stacking bearing walls above to bearings below.

Floor joist blocking requirements. Building code requires the use of blocking for floor joists that exceed 2 inches in width by 12 inches in depth. Rotation loads occur because when floor sheathing is resisting lateral loads oriented perpendicular to the joist those lateral loads are. Usually solid wood blocking or cross x wood blocking. Blocking is also needed each time the joist overlaps with a center beam and every eight feet between two joists.

Click to share on twitter opens in new window click to share on facebook opens in new window related. While full depth blocking is commonly used at cantilevers page 10 of the tji joist specifier s guide provides an alternate detail than can be used in certain applications. 4 4 requirements for blocking it is important in floor framing construction to prevent joists or trusses from rotating or displacing laterally from their intended vertical position. Add comment cancel reply.

Usually i stick it in somewhere around mid span. Viewfloor more from this author. Notify me of follow up comments by email. The international residential code irc requires lateral restraint to floor joists at supports.

Prev article next article. Since the span is short enough that even 2x8 s would have met the code it would be pointless to put blocking at the mid span of 2x10 s since they are already more than stiff enough. Blocking keeps taller joists from tending to twist onto their sides when heavily loaded. This simply means for it to rest directly on top of another framing member like a drop girder a wall or a pressure treated mud sill there is some criteria the joists must meet according o the 2012 international residential building codes.

Blocking panels are pieces of tji joists or solid sections of structural composite lumber scl that fit perpendicular between the joists blocking panels transfer both vertical and lateral loads through the floor. For me the solid blocking takes longer to install but i tend to feel it makes things more solid don t know if that is true or not. Section r502 7 of the 2009 international residential code specifies that joists must be laterally supported by solid blocking that s not less than 2 inches thick and the full depth of the joist. Floor joist blocking requirements.

The best way for a joist to transfer its load is for it to stack. As a matter of course for any joist size we recommend using blocking every 8 feet. Floor joist building code requirements. Blocking provides the floor joists with lateral support and it provides a way to transfer shear and vertical loads from the walls above to the foundation below.

Five primary uses of blocking are.