Floor Joist Bracing

Floor Joist Bracing Prevents Floor Squeaks and Reduces Floor Deflection

By Mark J. Donovan

In order to stiffen up a floor and prevent floor joists from flexing and twisting when put under heavy load floor joist bracing is employed. Floor joist bracing also helps to reduce squeaks and floor deflection.

There are two main types of floor joist bracing employed. Solid blocking and cross bracing (X bracing). Solid blocking provides the most support in preventing floor joists from flexing, however they can become impediments for running electrical wire and plumbing pipes between floor joist bays.

Cross bracing, on the other hand allows electrical wire and plumbing pipes to be easily snaked through floor joist bays, however it does not provide quite the same level of rigidity.

Solid floor joist bracing should be installed where floor joists overlap over a center beam, and are normally installed every 8 feet between floor joists that are equal to or taller than 2x10s. Typically you will find solid floor joist bracing or cross joist bracing centered over the length of the floor joists in most homes.

Building codes vary so make sure you check with your local building inspector to ensure proper floor joist bracing. Cross joist bracing is usually constructed out of 1×4 lumber however metal cross bracing ties are also commonly used. It is important when installing 1×4 cross bracing to not split the ends when nailing them to the floor joists, as this will weaken the bracing.

Floor joist bracing should also be installed prior to installing the floor sheathing. This will help to ensure proper and consistent spacing between floor joists which will help during the floor sheathing installation.

Floor joist cross bracing
If you are using treated lumber keep in mind that ACQ treated lumber is highly corrosive to metal hardware and fasteners. Consequently make sure you use stainless steel, or ACQ corrosive resistant nails or fasteners.

Likewise, if you are using metal cross bracing make sure that that they are coated in an ACQ corrosive resistant material.

Plumbers and electricians occasionally knock out cross bracing pieces when running wires and pipes and neglect to reinstall them when finished with their work. Make sure you go back and reinstall them after they have completed their work, or better yet ask them to reinstall them.

Room Addition Bid Sheet

For more help on building a home addition, see HomeAdditionPlus.com’s Home Addition Bid Sheets. Our Home Addition Bid Sheets provide you with the knowledge and information on how to plan a home building project, and what to look for when hiring contractors. They also include detailed cost breakdown tables and spreadsheets for estimating your own new home construction building costs.

Related Information

Additional Framing Resources from Amazon.com

Free Home Addition Price Quotes with No Obligation!

Fill out our 3-5 minute quick and easy form, and receive a free price quote on a house addition from one of our prescreened and licensed home addition contractors. This process is free and there is no obligation to continue once you receive your home addition price estimate.