Cross Members Between Floor Joists

Floor joist bridging is critical to the structural strength of a floor as shown in figure 1.

Cross members between floor joists.

B the framing member that runs around the perimeter of your house and that the floor joists butt into often gets riddled with large holes. Solid blocking should be used where floor joists overlap over beams. With the vent removed you have a wide clear view of a cross section of your floor. In general terms joists spaced 16 inches on center can span 1 5 times in feet their depth in inches.

Proper bridging distributes the load on the floor to other joists and over time prevents floors from sagging and squeaking do to floor joists twisting and warping. Removing a floor hvac vent is the best way to check for total floor thickness. It should be placed at eight foot intervals between any floor joists 2x10 or longer. Building code requires the use of blocking for floor joists that exceed 2 inches in width by 12 inches in depth.

When incorporated into a floor framing system joists serve to provide stiffness to the subfloor sheathing allowing it to function as a horizontal diaphragm joists are often doubled or tripled placed side by side where conditions warrant. What is the proper placement. Look inside old homes or warehouses and you ll often see funny cross. The cool thing about these however is that the space between cross members is usually big enough to accommodate big pipes even ductwork.

Yet it is not uncommon to find bridging not properly installed or missing all together. Providing more support and rigidity than cross bracing solid blocking is a reasonable alternative but can be an obstacle for running plumbing pipes and electrical wire between floor joists. A 2x8 up to 12 feet. If you have central heat and or air conditioning with floor vents it is very easy to remove the vents by pulling them straight up.

Be aware that lumber yards have a far greater inventory of floor joists than the home centers or big box stores. The common spacing between floor joists is 16 inches on center. A lot of questions revolve around joists when it comes to building a deck. Tom silva explained that the cross bridging transferred the load on the joist to the other joists thus strengthening the floor.

2x10 to 15 feet and 2x12 to 18 feet. Absolutely visit a real lumber yard to get some advice on strong and affordable floor joist lumber. Blocking is also needed each time the joist overlaps with a center beam and every eight feet between two joists. A joist is a horizontal structural member used in framing to span an open space often between beams that subsequently transfer loads to vertical members.

How far apart are floor joists placed. This is contrary to my understanding of the purpose of bridging.