Floor Joist Placement

A floor s framework is made up mostly of wooden joists that run parallel to one another at regular intervals.

Floor joist placement.

Study the blueprint and make note of the location of any stairway openings floor joist cantilevers in construction floor beams and heavy loads from above. Continuing on from part 1. In general practice 2x8s 2x10s or 2x12s are used when framing a raised floor instead. The amount of flex that is acceptable in the floor you can play with a joist span calculator here.

In the past 2x4s or 2x6s were sometimes used as floor joists. Any large knots found near the edge of the board should face up as well so the weak wood of the knot will be compressed rather than stressed. Ceiling joists are usually 2 by 6s or sometimes 2 by 4s if it is an older home. This size is no longer acceptable when framing a structure.

Some newer homes have manufactured i beam shaped joists. When possible position floor joists with any crook in the board facing up so the weight on the joist will tend to straighten it out. Residential structural design vertical structural forces we were about to start learning about floor joist span tables. Floor joists are typically 2 by 8s 2 by 10s or 2 by 12s.

Good luck and keep us up to speed with your progress j. Rock shims or hand packed and pounded smaller stones will stiffen the post placement and allow for proper drainage. All these conditions are important when determining floor joist placement on sill plates and beams. The exact size necessary may be stipulated by the building code required for a particular structure.