In general a double 2x beam can support a span in feet equal to its nominal width in inches. A double 2x10 can thus span 10 feet.
Some manufacturers limit their beams to 60' due to transportation issues, while others have the capability to manufacture beams up to 80' long. So, the longest unsupported span possible using LVL would be 80-feet. Typically, though, it is common for a continuous LVL span to be between 20' and 30'.
For instance, a double 2×12 beam can span 12 feet; a (2) 2×10 can span 10 feet and so on. Joist sections cantilevered over beams must be calculated as (2x length) for beam sizing.
For example, a double 2×8 beam can span 8-ft.
The recommended maximum extension for a cantilevered exterior deck is four feet. In this situation, 2X joists should extend back into the floor at least eight feet, using a recommended 2:3 ratio. It is possible to extend beyond four feet but each situation must be examined and analyzed for structural capacity.
With a 12' deck span, the beam may be either two 2X8's or two 2X10's, depending on the wood used.
**Beams**: To span 20 feet without a support post in the middle, you typically need at least a 4x12 or 6x12 beam, depending on the type of wood and load requirements.
Beams shall be permitted to cantilever at each end up to one-fourth of the actual beam span. Deck beams of other materials shall be permitted where designed in accordance with accepted engineering practices.
You can use a W12x35 (50 ksi) steel beam for your 24' clear span beam. The beam is 6.5” wide and 12.5” deep. It weighs 35 pounds per foot of beam length. You will need to provide solid mechanical connections of each of the floor joists to the steel beam.
Your approximate limit for the quadruple 2x10 would be a clear span of 9'.
One of the major differences between LVL and conventional lumber is that – due to the emphasis placed on quality bonding in LVL – there are no naturally occurring knots. This not only makes the product stronger, but more durable than conventional lumber.
Typical spans for wooden beams range from 8 to 12 feet, depending on the load they need to bear. Steel or engineered wood beams can span longer distances, often exceeding 20 feet.
As shown in the table below, a single 2x10 beam can span 6 feet while carrying 2x8s spanning 8 feet and cantilevering another 2 feet. Lesson: When beam spans are less than 8 feet, you may be able to use a single-ply beam.
A beam span is the length of a line of girder or other beam type construction extending from one end to the other, measured in feet. A span can be obtained by multiplying the height of the structure by the desired beam width.
In general a double 2x beam can support a span in feet equal to its nominal width in inches. A double 2x10 can thus span 10 feet.
A rule of thumb for beams is that they need to be ½ their span deep. In ancient times, a horizontal structure was called the entablature and had three parts: architrave (main beam); frieze (cross beams and ornamental sculpture) and cornice (overhanging crown).
The size of the beam you need for a 22 ft span depends on the type of beam, the load it will be supporting, and the desired deflection. Here are some general guidelines: Wood beams:A 2x12 wood beam can span 22 ft with a live load of 40 psf and a deflection of 1/240 of the span.
For example, a 2x6 joist would have a 12-foot, 6-inch maximum span, and a 2x10 joist would have a 21-foot maximum span. Additionally, wood species and grading determines how far apart floor joists can be spaced. Harder woods can be spaced farther apart, and can be cut into larger joists.
With a 12' deck span, the beam may be either two 2x8s or two 2x10s, depending on wood used. and footing sizes.
For a 2-ply 2x10 beam, the capacity depends on the wood species and grade. Common species like Southern Pine or Douglas Fir typically have capacities around 500-600 plf per ply over a short span like 10 feet. Therefore, a 2-ply 2x10 beam would have an approximate capacity of: Capacity per Ply = 500-600 plf.
The length of the cantilever.
If you upgrade to joists that are 2 by 10, the building code will allow you to cantilever for over 5 feet.
6, the allowable joist span for a 2x10 would be 11 feet 5 inches, with a maximum cantilever (taken from the “10” joist-back-span column) of 2 feet 6 inches, for a total span of 13 feet 11 inches. Even adding 2 1/2 inches for the ledger and half the hanger seat, the total maximum deck depth is 14 feet 1 1/2 inches.
2x4 11'-6" 2x6 17'-0" 2x8 21'-8" 2x10 25'-7" 24" O.C.