While most residential construction uses 2x8 joists with 16 inch spacing there are many other factors you need to consider when determining the proper joist span length.
2x4 floor joist span.
Span calculator for wood joists and rafters also available for the android os.
This calculator shows 2x4 s limited to 5 8 span for eastern white pine.
Simplified maximum span tables for selected visual and mechanical grades of southern pine lumber in sizes 2 4 thru 2 12.
2 grade of douglas fir are indicated below.
There are online span calculators available that tell you the maximum span for.
Bottom edges of joists must be free of wires pipes and ducts.
The depth or height of your floor joists depends on how far they can span without sagging.
1 psf lb f ft 2 47 88 n m 2.
Live load is weight of furniture wind snow and more.
Shorten the span maybe to 5 and put them 12 oc or like mac said 4 16 oc.
Check out this free calculator or consult floor joist span tables for what you are doing.
When building a house or even a deck it is important to confirm you have the correct joist sizes spans and spacing before you get started.
Use a temporary 2x4 post at the midpoint of the span to support the joist until the adhesive cures usually in 24 to 48 hours.
Doesn t interfere with plumbing or wiring in joist bays.
I personally think it will be a bouncy floor.
Listed are 46 tables based on common loading conditions for floor joists ceiling joists and rafters.
Dead load weight of structure and fixed loads 10 lbs ft 2.
Maximum floor joist span for no.
1 ft 0 3048 m.
View joist rafter tables.
If you use awc calculator 2x4 can span 6 2 with l360 deflection for decks 40lb ll.
All floor joist tables start with 2x6 lumber.
Also the type of lumber is important.
While every effort has been made to insure the accuracy of the information presented and special effort has been made to assure that the information reflects the state of the art neither the west coast lumber inspection bureau the american wood council nor its members assume any responsibility for any particular design prepared from this online span calculator.
This means that it will be hard for you to convince your planning department to approve your plans without some sort of proof that the 2x4 s are adequate.
Most spans are typically 10 to 12 feet so we typically use 2x8 or 2x10.
