# Quick Answer: How Big Of A Beam Do I Need To Span 20 Feet?

## How far can a 2×6 Rafter span without support?

The table states that 2 X 6 rafters spaced 16 inches on center (o.c) can span a maximum distance of 13 feet 5 inches.

Another option are 2 X 8 rafters spaced 24 inches o.c..

## How far can you span a 2×12 for a roof?

Max. Live Load 20 lbs/ft2 (956 N/m2)Maximum Span (ft – in)Nominal Size (inches)Rafter Spacing, Center to Center, OC (inches)Lumber Grade2 x 121233′ – 6”1629′ – 5”2424’10 more rows

## What size beam do I need to span 15 feet?

As the table shows, no 2×8’s meet the span and spacing requirements, but a 2×10 with an E of 1,300,000 psi and Fb of 1093 psi can span 15 feet 3 inches – more than enough. A 2×12 with an E of 800,000 psi and Fb of 790 psi also works, since it can span 15 feet and 10 inches.

## How far can a 4×4 span without support?

Common Post Spacing In general, the maximum span for a 4-by-6 beam is 6 feet between 4-by-4 posts. If you move up to 4-by-8, you’re usually allowed to span up to 10 feet between posts. A 4-by-10 can usually span up to 12 feet between posts.

## How much weight will a 4×4 beam support?

A piece of yellow pine in an inside dry location can hold 1200 pounds per square inch and a 4″ x 4″ is really 3 1/2″ X 3 1/2″ or 12.25 square inches times 1200 is 16150 pounds. A denser hardwood like Oak would hold a lot more. These numbers were gathered from the internet.>>

## How much weight can a 2×12 beam hold?

2 Answers. Putting those numbers into the sagulator, a 12′ 2×12″ Ponderosa pine board lying flat could support 100-125 lbs with about 0.2″ of sag in the middle. If it were on edge, it could support several thousand pounds.

## How far can a beam span without support?

When supporting joists that span 12 feet with no overhang beyond the beam, a double ply beam can span in feet a value equal to its depth in inches. A double 2×12 beam can span 12 feet; a (2) 2×10 can span 10 feet and so on.

## How big of a LVL beam do I need?

Design a beam depth based on the rule of thumb for estimating the depth of manufactured beams which is to divide the span by 20. Beam depths are typically 5 1/2 inches, 7 1/4 inches, 9 1/4 inches, 11 1/4 inches, 11 7/8 inches, 14 inches, 16 inches, 18 inches, and 20 inches.

## How far can a 6×6 beam span without support?

Each 6×6 beam only spans 12 feet, of which 2 of those feet are supported by a knee brace. So technically the beams only span 10ft.

## How far can a triple 2×6 beam span?

A triple 2×6 beam over a span of 10′ feet should be more than sufficient for normal deck loads. Maximum span for a single 2×6 #2btr yellow pine is around 9′ feet. So YES you should be fine with triple 2×6..

## Can floor joists span 24 feet?

2. Spans are clear distances between supports, and are based on composite action with glued-nailed APA Rated® sheathing or Sturd-I-Floor® panels of minimum thickness 19⁄32 (40/20 or 20 o.c.) for joist spacing of 19.2 or less, or 23⁄32 (48/24 or 24 o.c.) for a joist spacing of 24.

## Should I use 4×4 or 6×6 for pergola?

To adequately support the lumber overhead as well as give the pergola a sturdy look, you’ll probably need to use 6×6 for the support posts. For a very small pergola with only 4 to 6 feet between posts, 4×4 supports will work.

## What size ridge beam do I need to span 20 feet?

If it is a 20′ span in the ridge beam you could easily need 3-18″ LVL’s if not more and 18′ rafters will probably need to be 11 7/8’s I joists.

## How far can a 2×12 beam span without support?

In general terms, joists spaced 16 inches on center can span 1.5 times in feet their depth in inches. A 2×8 up to 12 feet; 2×10 to 15 feet and 2×12 to 18 feet. The larger the deck, the larger the joists.