Fire Blocking Floor Joists

Fire blocking locations 2x fire blocking 2x fire blocking 2x fire blocking stringer header ceiling joist floor joist stair stringers the space between stringers must be separated from the upper story floor joist bays.

Fire blocking floor joists.

Material for fire blocks. You can insulate second floor rim joists following the same steps shown here if you happen to tear out a ceiling during remodeling. Building code requires the use of blocking for floor joists that exceed 2 inches in width by 12 inches in depth. Any time a duct plumbing pipe or electrical wire goes through a floor or ceiling it must be sealed around it with some type of fire stop.

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. Rigid foam is the best insulation for rim joists. In addition to providing lateral support blocking helps transfer weight to adjacent joists so that the floor acts as a unified system. Step 4 fire blocking floor and ceiling openings all penetrations through the plates on a wall must be sealed with a foam caulk or insulation that is fire rated.

Fire blocking designed to slow down the spread of fire from one floor of your house to the next. Typically inspectors are looking for fire blocking in the gaps between the foundation wall and the framed wall of your basement specifically at the top of that wall area. The blocks must be as wide as the wall. The drywall that is your ceiling is a form of fire blocking.

Bonus rooms if the floor level ties into a stud wall. The block is nothing more than a 2 x 6 or fire rated drywall turned flat and attached to the bottom of the first floor joists. Additional support for the floor joists is achieved by nailing the ends of the joists into headers. Landings if the area underneath the landing is unfinished the wall bays must be blocked.

Blocking also needs to be provided at the supporting end of a joist. It acts as a cap at the top of your framed basement wall to contain any fire in the wall long enough to alert the smoke alarms in the basement see illustration at bottom. The most often used product is a expanding. For a 2 x 4 wall use a 2 x 4 block for a 2 x 6 wall use a 2 x 6 block.