Fire Blocking Floor Joists

You can insulate second floor rim joists following the same steps shown here if you happen to tear out a ceiling during remodeling.

Fire blocking floor joists.

The drywall that is your ceiling is a form of fire blocking. Material for fire blocks. For a 2 x 4 wall use a 2 x 4 block for a 2 x 6 wall use a 2 x 6 block. 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.

Bonus rooms if the floor level ties into a stud wall. Additional support for the floor joists is achieved by nailing the ends of the joists into headers. 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. In addition to providing lateral support blocking helps transfer weight to adjacent joists so that the floor acts as a unified system.

Blocking also needs to be provided at the supporting end of a joist. Landings if the area underneath the landing is unfinished the wall bays must be blocked. 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.

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 2012 international residential code allows for the use of materials other than standard lumber although i do not recommend any of. Floor joist floor above solid sawn or i joist w attached ceiling ceiling finish material space between each floor joist 1 000 sf solid sawn joists or other solid joists such as i joists provide more than adequate draftstoppingwhen the ceiling finish is added to the bottom of the joists. 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. The blocks must be as wide as the wall. Building code requires the use of blocking for floor joists that exceed 2 inches in width by 12 inches in depth. 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.