Cutting A Floor Joist Out Of The Floor Above

Codes don t directly address how many holes and notches you can cut in a joist.

Cutting a floor joist out of the floor above.

The fire burned through a section of one of the floor joists and the homeowners wanted to replace it without tearing up the finished wood floor and subfloor above. A nominal 2 8 board measures 1 1 2 by 7 1 2 inches cutting the new joist. The notching and boring rules of thumb for solid lumber are shown in fig. One of our recent whole house balloon frame remodeling projects had a floor so out of level that anyone sitting on the toilet in the future bathroom risked sliding off.

I was careful not to cut too deep where i suspected the floor joists were and came back and finished cutting over the top of them with the reciprocating saw laid down as much as possible. The three main types of floor joists used in home construction are solid lumber i joists and open web floor trusses. The space between the beam and the floor boards above was 7 inches so i decided to use regular framing lumber and rip a 1 2 inch off the width of a 2 8 framing member. But sometimes you have to cut out an old floor joist and put in a new one.

If your home is more than 20 years old your floor joists are most likely solid wood 2x8s 2x10s or 2x12s. The only problem was the subfloor was nailed to the floor joist with some very large nails and they did not come out very easily. Finish cutting out the square by cutting parallel to the joists inside. When installing a new joist on a foundation wall you may need to notch the bottom edge so it.

Cut into floor along the lines between the joists but several inches inside your marks for the centerlines of the joists.