Boxing Floor Joists

After several centuries of service floor joists in older homes may sag or crack.

Boxing floor joists. If there is a floor above the ceiling you re good to go as these are floor joists that are sized for the load above. Things might work out for a while but you will have a high likelihood that the floor will flex and your tile will crack. The new joist fit in the space sideways but would not tilt into vertical position. An average ceiling joist is made of a 2 6 board.

Doubling of joists is recommended under walls heavy objects like tubs and at large openings. The first thing to determine is the joist size. True floor joist span calculations can only be made by a structural engineer or contractor. Reinforcing floor joists is best done by doubling of floor joists.

Standard spacing for ceiling joists is every 16. A ceiling joist is basically a large board that supports your ceiling and if you have one the floor above. The reason was the corners of the new joist when at a 45 degree angle caught the top of the beam and the bottom of the floor boards. A 2 x 4 joist can probably hold a heavy bag but it could flex.

How to make floor joists stronger. B the framing member that runs around the perimeter of your house and that the floor joists butt into often gets riddled with large holes this space is the logical exit point for dryer and furnace vents big electrical service wires and fireplace fresh air intakes. Even worse is that over time any rot or decay from moisture that these cut up joists see will result in a dangerous situation where if the job was done right the joists would be able to handle the load. Long spans of joists in newer homes may wobble or bounce from foot traffic.

But they can range from a 2 4 to a 2 12 depending on the construction of your home and what that joist is supporting. This sample table gives minimum floor joist sizes for joists spaced at 16 inches and 24 inches on center o c for 2 grade lumber with 10 pounds per square foot of dead load and 40 pounds of live load which is typical of normal residential construction. This is the secon. If the ceiling is in a closet or below an attic these may be just ceiling joists that could be as small as 2 x 4s.