Double Header Floor Joist

Most floor joists consist of 2 by 6 inch lumber but they can use 2 by 8 or 2 by 10 as well which will require longer joist hangers.

Double header floor joist.

Doubled up the tjis with blocking between them on either side of the staircase. Double and triple joist hangers. Now i need a double header located directly above the bottom of the staircase for two more tji to. Floor is 11 7 8 tji.

Headers run perpendicular to the direction of the joists and you will attach the headers to the ends of the cut joists for support. Section r502 10 of the international residential code states that header joists can be the same size as the floor joists when the header joist span isn t greater than 4 feet but if the header joist span is more than 4 feet you ll need to double the header joist and ensure that it s capable of. You ll need headers on both sides of the new opening. Direct nail the first header in to the cut joist and through the trimmer joists in to the header.

When a load is applied to one side of a double joist by another joist or header for example then the double joist must be connected together so both joist. To stabilize the cut joists you ll have to install headers that run between the solid joists on either side of the cut joists. However if the loading is applied from above through floor sheathing through a load bearing wall or post that rests on both joists then no attachment between joists is required. Double and triple joist hangers are wider to accommodate either a thicker piece of lumber or two or three joists placed side by side.

There is a 4 wide staircase cutout that runs parrallel to i joists right in the center of the floor. Additional support for the floor joists is achieved by nailing the ends of the joists into headers. Add the second header and direct nail this header through the trimmer joists.