Improper Bridging Between Floor Joists

Mike installs galvanized steel briding in between the floor joists on this bedroom addition project in rocky hill ct.

Improper bridging between floor joists.

From a structural perspective you are correct. Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor. Long spans of joists in newer homes may wobble or bounce from foot traffic. Simpson strong tie tension bridging galvanized steel the ltb s are used in floor systems to resist the overturning of floor joists and features a staggered nail pattern.

The extra two inches of vertical distance when a floor is framed with 2 x 10 joists rather than 2 x 12s can be quite important for example. For example with bridging installed between joists a piano leg sitting over one 2 10 is actually supported by several. Install with two 6d common nails per end. But larger is not always better when builders are constructing a home or adding a room addition.

Thd sku 205173. After several centuries of service floor joists in older homes may sag or crack. How to make floor joists stronger. The blocking or bridging between joists or rafters also contributes to this phenomenon.

Building code requires the use of blocking for floor joists that exceed 2 inches in width by 12 inches in depth. Yet it is not uncommon to find bridging not properly installed or missing all together. 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. Various types of metal bridging are available at home centers and lumberyards.

Additional support for the floor joists is achieved by nailing the ends of the joists into headers. From both ends of the span. Adding two rows of bridging costs a few dollars per joist. To install the type shown here drive the toothed end into the joist and nail the other end.

Blocking is also needed each time the joist overlaps with a center beam and every eight feet between two joists. Solid blocking and metal or wood x type bridging do accomplish the same task.