Maximum deflection is limited by l 360 or l 480 under live load.
2x4 truss floor joists.
Tcll top chord floor live load 2.
Basic lumber design values are f 2000 psi f 1100 psi f 2000 psi e 1 800 000 psi duration of load 1 00.
Build a fink truss to bolster a floor roof or deck.
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.
In the example the joists have a spacing of 16 inches and a span of 11 feet 2 inches.
There are many ways to frame a floor but i believe 2x4 trusses make the best floor.
Top and bottom chords braced by structural sheathing 6.
Openings are to be located in the center of the span max opening width is 24 inches 7.
Floor trusses are not fire code friendly.
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.
In this case your joists are adequate to support a 30 psf live load and 10 psf dead load.
Spacing of trusses are center to center in inches.
Spans shown are in feet 4.
Slight alterations can be made on site if necessary as.
Using floor trusses allows you to utilize eight foot basement walls as the ductwork is installed within the openings of the floor truss.
Live load l 480 total load l 360 5.
To which rick responded.
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.
Both floor trusses and floor joist systems provide suitable structural support.
In jurisdictions where recent versions of the irc fire code are enforced a protective membrane must be installed on the underside of plated truss floor framing.
In this video i ll show you the options and make the case for trussed flo.
Because they are manufactured off site according to the specifications of the project the need for alterations is almost completely eliminated.
Tcdl 10 psf and bcdl 5 psf 3.
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.
For a floor span of over 24 trusses are certainly the way to go.
Floor trusses though are an economical alternative to joists.
In a fink truss the internal joists are arranged in a w shape ensuring even weight distribution from one end to the other.
