How To Make 2x4 Floor Trusses

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.

How to make 2x4 floor trusses. Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. While they flex more than i joists they flex less than lumber trusses and use less wood. Live load is weight of furniture wind snow and more. Spacing of trusses are center to center in inches.

The depth or height of your floor joists depends on how far they can span without sagging. Maximum deflection is limited by l 360 or l 480 under live load. Raised floor living in conjunction with southern forest products association developed a table to help understand how trusses are built. Open web floor trusses are constructed with 2x4 boards on the top and bottom with a web of diagonal boards in the middle secured with metal plates.

1 psf lb f ft 2 47 88 n m 2. There are online span calculators available that tell you the maximum span for. Bottom chord bearing bottom chord bearing trimmable ends top chord bearing and mid block bearing are all available. Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters.

I joists offer only one bearing. Build a fink truss to bolster a floor roof or deck. Dead load weight of structure and fixed loads 10 lbs ft 2. Maximum floor joist span for no.

1 ft 0 3048 m. 2 grade of douglas fir are indicated below. Most spans are typically 10 to 12 feet so we typically use 2x8 or 2x10. Step 1 lay the two pieces of 2 by 4 by 144 inch lumber on a worktable.

The multiple bearing conditions make matching existing floor heights much easier when using floor trusses. Floor trusses offer four different bearing conditions for a wider variety of uses. Trusses are beneficial in that the open spaces in the middle make it easy to run utilities through them.