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The Daily Insight

How far can you span a 4×8

Author

Rachel Hickman

Published Apr 02, 2026

Joist SpansDouglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir, Redwood, Cedars, Ponderosa Pine, Red Pine4X66′-2″4X88′-2″4X109′-8″4X1211′-2″

How far can a 4X8 LVL beam span?

Due to its strength, an LVL beam can span up to 60 feet and is much stronger than traditional lumber. Generally, you can find LVL beams in 4-foot increments starting at 24 feet and going up to 44 feet long, with special orders up to 60 feet. LVL beam thickness is usually between 1 ¾ and 7 inches.

What size lumber can span 24 feet?

Maximum Span (ft – in)Nominal Size (inches)Joist Spacing Center to Center (inches)Lumber Grade2 x 61212′ – 0″1610′ – 11″249′ – 7″

How far can 4X6 beam span?

A Redwood 4×6 beam should span no more than 6′ between supporting posts.

How big of a beam do I need to span 20 feet?

Wood beam size for a 20 foot span:- as per general thumb rule, for a 20 foot span, size of wood beam or lumber joist should be 2×14 which placed at 16″ apart from centre used for residential building or projects or construction in which depth of section of beam is 350mm (14″) and width of beam is 50 mm or 2″.

What size beam do I need for a 16 ft span?

LVL beam size for a 16 foot span:- as per general thumb rule, for a 16 foot span, size of LVL beam or GLULAM should be 7-8 inches deep and 3 inches wide, thus you need something like a 7-8″ GLULAM or LVL to span upto 16 feet used for residential building or projects.

What size beam do I need for a 24 foot span?

For 24 foot span, size of simply supported beam for 2-3 storey residential building, using thumb rule, is about 15″×18″ in which beam width is 12″ and beam depth is 15″, if width will be kept 12″, depth should increased, then beam size 12″×24″ can be used, providing with 4nos of 16mm bar at top, 4nos of 20mm bar at …

Is a 4x6 stronger than 2 2x6?

In the bottom case the 4×6 is theoretically 2² = 4 times as strong as a single 2×6, but since there are two of them it is only twice as strong as two2x6s. Because of this, joists are used on edge rather than on flat.

How far can a 4X8 beam span without support?

Joist SpansDouglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir, Redwood, Cedars, Ponderosa Pine, Red Pine4X66′-2″4X88′-2″4X109′-8″4X1211′-2″

How far can a 6x8 span?

According to Western Woods Use Book by West Coast Lumbermen’s Association, 1973 edition, a 6×8 beam can support about 8,000 lbs., depending on species of wood, grade, etc. on an 8′ span.

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Can a 2x8 span 20 feet?

The distance a 2×8 can span depends on species, grade, purpose, location, loads, and several other factors. Joist spans range from 7′-1” to 16′-6 when all factors are considered. Most select structural (SS) and #1 grade lumber will span 12-feet or more, with SPF falling shy of that span.

How long can rafters span?

The maximum span for roof rafters is 23′ 9”. For headers, the maximum span is 11′ 2”. Finally, a single deck beam has a maximum span of 5′ 11” and double maxes out at 8′ 9”. However, the maximum is determined by the species and grade of wood, the spacing, the load, and more.

What size beam do I need for a 15 foot span?

Wood beam size for a 15 foot span:- as per general thumb rule, for a 15 foot span, size of wood beam or lumber joist should be 2×10 which placed at 16″ apart from centre used for residential building or projects or construction in which depth of section of beam is 250mm (10″) and width of beam is 50 mm or 2″.

How far can a 8X8 beam span?

From contributor I: 20 to 25 feet is a serious span – an 8X8 won’t even come close.

How far can 2x12 span?

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. Given a design span of 15 feet 1 inch and a 16 inch joist spacing, first determine which size lumber will work.

How big of a header do I need for a 8 foot span?

Header SizeMaximum SpanNumber of TrimmersDouble 2×64 ft., 0 in.OneDouble 2×85 ft., 0 in.TwoDouble 2×106 ft., 2 in.TwoDouble 2×127 ft., 1 in.Two

How much is a 24 foot beam?

LengthI-Beam CostH-Beam Cost24′$145 – $430$265 – $38530’$180 – $540$330 – $48040’$240 – $720$440 – $640

How far can a 2x6 span without support?

A 2×6 can support up to 50 pounds per square foot of weight without sagging with a maximum span of about 12 feet when spanning a distance horizontally, with the 2×6 standing in a vertical position. This number includes both live and dead weight.

How far can you span a 2x4 ceiling joist?

A 2×4 can span a maximum of 6′ 7” when spaced 16” apart and used as a floor or deck joist. When used as a ceiling joist or a roof rafter, a 2×4 can span up to 7′ 3” spaced at 16”, and 6′ 4” when spaced 24” apart.

What size beam do I need for a 10 foot span?

A double ply beam can span in feet if there is no overhang beyond it. A double 2×12 beam can span 12 feet, a double 2×10 can span 10 feet, and so on.

How much weight can a 4x6 beam support horizontally?

2 Answers. Assuming it’s “Lodgepole Pine” (Idaho Pine and Ponderosa Pine is slightly less) and it’s grade is a No. 2 and better (no loose or missing knotholes), then a 4×6 spanning 18′ will support about 105 lbs.

How far can 2x10 floor joist span?

Douglas fir 2-by-10 joists graded as “Structural Select” allows joist spans up to 21 feet for a live load of 30 pounds per square foot when spaced 12 inches apart, 19 feet 1 inch for 16 inch spacing and 16 feet 8 inches for 24 inch spacing.

How much load can a 4x6 support?

The load capacity of a 3-foot #2 grade 4×4 is 17,426 pounds, and a similar 6×6 is 20,834 pounds or 16% better. However, an 8-foot 4×4 supports 6468-pounds and 2339-pounds at 14-feet, while a 6×6 is 18032 and 10550-pounds respectively – or 64% and 78% more load capacity.

What is stronger 4x6 or 2x8?

Unless it comes a ways from the pith of the log it will be stronger if it comes from a “boxed heart” timber. A good 2×8 will support as much as a 4×6.

Is 2x12 or 4x6 stronger?

For a partial answer, depth of a beam has more contribution to strength than the width. So, NO, the 4×6 is not as strong as the 2×12, all other things being equal.

How much weight will a 8x8 wood beam support?

If a particular species of wood can support 1,000 psi, then an 8×8 post can hold 64,000 pounds!

How much weight will a 6x6 beam support?

A 6×6 with 12′ span can support 2000 lbs. if you assume a conservative 1400psi bending stress. If you do a good job bonding the two members together, your double 6×6 can support more than 4,000 lbs.

How far can heavy timber span?

Timber trusses can readily be built to span 30 to 60 ft., and longer spans are possible.

What size beam do I need to span 25 feet?

Wood beam size for a 25 foot span:- as per general thumb rule, for a 25 foot span, size of wood beam or lumber joist should be 2×16 which placed at 16″ apart from centre used for residential building or projects or construction in which depth of section of beam is 400mm (16″) and width of beam is 50 mm or 2″.

How far can a 2x8 span for a roof?

Maximum Span (ft – in)Nominal Size (inches)Rafter Spacing, Center to Center, OC (inches)Lumber Grade2 x 62413’2 x 81221′ – 7”1619′ – 7”

How much load can a 2x8 support?

Span (feet)Weight Supported (lb)2 x 2″ x 6″2 x 2″ x 8″42250469061680313082660