Floor Load Width Explained

This is referred to as the floor load width flw.

Floor load width explained.

An inaccessible attic space on the other hand might have a live load of only 20 psf. If there s wall board covered ceiling suspended from the underside of that floor the dead load increases to about 10 pounds per square foot. First floor live loads have higher requirements than second floor live loads 40 pounds per square foot vs. In order to reduce size and or height of the reinforcing beam under the tracks reduce the track spacing as required.

A floor joist appropriately selected to span 10 feet with an l 360 limit will deflect no more than 120 360 1 3 inches under maximum design loads. Bearer floor joist design example simple rectangular shaped light weight home floor joists bearers 3600 section gable roof 25o pitch steel sheet. The dead load on a floor is determined by the materials used in the floor s construction. Drywall attached to the underside of this system is not expected to crack when the floor joist system deflects 1 3.

In both instances the floor load width is equal to the sum of half of the total span on either side of the bearer total span 4m floor load width 2m for a visual representation of the floor load width see the sketch below. A room used solely for sleeping might need to carry only 30 psf whereas a garage floor over a basement would need 50 psf or higher. Example flw floor if x 2000mm load width y 4000mm a 900mm flw a x 2 a flw a 1900mm flw b x y 2 flw b 3000mm flw c y 2 flw c 2000mm 79. Floor loads whether the bearers are supporting load bearing walls or only floor loads the area of the floor supported by an individual bearer must be determined.

A typical wood frame floor covered with carpet or vinyl flooring has a dead load of about 8 pounds per square foot. Where the bearer supports load bearing walls the type of roof covering also needs to be determined. Floor load width flw 78. The load is an average value.