The span table for a 30 psf live load 10psf dead load floor indicates a required fb value of 1 315 and a minimum e value of 1 800 000.
2x4 truss floor joists.
To which rick responded.
Basic lumber design values are f 2000 psi f 1100 psi f 2000 psi e 1 800 000 psi duration of load 1 00.
In the example the joists have a spacing of 16 inches and a span of 11 feet 2 inches.
In this case your joists are adequate to support a 30 psf live load and 10 psf dead load.
In this video i ll show you the options and make the case for trussed flo.
Tcdl 10 psf and bcdl 5 psf 3.
Floor truss span tables alpine engineered products 17 these allowable spans are based on nds 91.
Floor trusses are going to run around 4 40 per lineal foot spaced 2 on center this makes the cost per square foot for the joists at 2 20.
In a fink truss the internal joists are arranged in a w shape ensuring even weight distribution from one end to the other.
There are many ways to frame a floor but i believe 2x4 trusses make the best floor.
Both floor trusses and floor joist systems provide suitable structural support.
Maximum deflection is limited by l 360 or l 480 under live load.
Floor trusses though are an economical alternative to joists.
Tcll top chord floor live load 2.
Because they are manufactured off site according to the specifications of the project the need for alterations is almost completely eliminated.
Shop our wide selection of stock and custom floor trusses to complete your building project available in a variety of styles and sizes to fit your needs.
Openings are to be located in the center of the span max opening width is 24 inches 7.
Build a fink truss to bolster a floor roof or deck.
Fink trusses were originally invented for the purpose of beefing up bridges but many contractors now use them to increase the strength of interior structures.
Spacing of trusses are center to center in inches.
For a floor span of over 24 trusses are certainly the way to go.
Live load l 480 total load l 360 5.
Additionally having the mechanicals and ductwork hidden within the web openings of the floor truss allows for the easy installation of drywall to the bottom chord of the floor truss to finish off a ceiling.
I m thinking it would take a little more math on the builder customer part to compare against labor.
Slight alterations can be made on site if necessary as.
Spans shown are in feet 4.
Using floor trusses allows you to utilize eight foot basement walls as the ductwork is installed within the openings of the floor truss.