2×8 Span Chart
| Maximum Span | Maximum Span | Maximum Span | |
| Species / Spacing (inches on center) | Floor Joist | Deck Joist | Roof Rafters (Snow-Load) |
| Southern Pine | |||
| 12 | 15’ 10” | 13’ 1” | 15’ 10” |
| 16 | 14’ 5” | 11’ 10” | 14’ 5” |
What is the maximum span for a 2x10 floor joist?
3 rows · 22/04/2020 · What is the maximum span for a 2x8 floor joist? In general terms, joists spaced 16 inches on ...
Can you use 2x8s for joists?
3 rows · What is the maximum span for a 2×8 floor joist? In general terms, joists spaced 16 inches on ...
How far can a 2x8 floor span?
12 rows · Depending on various factors, the maximum span for a 2×8 floor joist is 16’ 6”. The maximum ...
How far can a 2x10 beam span?
2x4 2x6 2x8 2x10 2x12. Grade. Select Structural No. 1 No. 2 No. 3 Stud Construction Standard Utility. Member Type. Floor Joists Ceiling Joists Rafters (Snow Load) Rafters (Roof Live-Load) Deflection Limit. L/720 L/600 L/480 L/360 L/240 L/180. Spacing (in) 12 16 19.2 24.
How far can a 2x8 span without support?
Based on different manufacturers' specifications, the maximum span a 2×8 LVL is from 12' to 15'. Spans are also affected by the species of wood used in the manufacture of the laminated joists, with western woods edging out eastern woods in unsupported span distance.
How far can a double 2x6 span without support?
How Far Can a Double 2×6 Beam Span? A double 2×6 southern pine beam can span a maximum distance of 6 feet 8 inches when supporting joists that span 6 feet, according to International Residential Code.
Can you use 2x8 for floor joist?
The span for a 2×8 floor joist can range from 7' 1” to 16' 6”. In addition, floor and deck joists have to support a fairly high live load because they provide support underneath living areas. You may find that a 2×8 does not offer the necessary support on its own.
Should I use 2x6 or 2x8 for deck?
For upper-level decks, 2x10 is recommended as the minimum size to use for strong guard post connections. 2x6 joists should only be used on ground-level decks that do not require, and will not provide for, any guards. ... Most decking is not strong enough to support longer spans than 16".
2012 version of the Span Calculator for Wood Joists and Rafters
Uses wood properties from the 2012 NDS. Results from this calculator do not reflect the latest information, contained in the 2018 NDS.
Important note about 2012 Span Calculator
The 2012 version of the AWC Span Calculator uses wood properties from the 2012 NDS. Results from this calculator do not reflect the latest information contained in the 2018 NDS.
2021 version of the Span Calculator for Wood Joists and Rafters
Uses wood properties from the 2018 NDS (the most recent version). Please email info@awc.org if you encounter issues.
What is the difference between a floor joist and a rafter?
Floor joists span from wall to beam or wall to wall with supports spaced to optimize the strength of the building material used , or to determine the materials to be used . Rafters span from the top plate to ridge board or beam but may have intermediate support from purlins and braces, collar ties, or raised rafters.
How many feet does a 2x8 span?
A rule of thumb is 1.5 times a joist’s depth but in feet when spaced at 16” centers. In general, a 2×8 will span 1.5 x 8, so 12-feet. Based on all factors though, a 2×8 joist span is 7’-1” to 16’-6”, and a rafter 6’-7” and 23’-9”. In this guide, we’ll explain ...
Which is stronger, Douglas Fir or Douglas Fir Larch?
The species, type, or kind of tree determines the structural strengths of the timber and impacts support, flexing, and compression abilities. Douglas fir-larch is stronger than spruce-pine-fir (SPF) and will span further when other factors are the same.
What is the load a structural member may carry?
The load a structural member may carry limits the distance it can span before it is structurally compromised. Floor and ceiling joists and rafters must support the dead weight or load of all structural materials and furnishings or fixtures in their support area, plus any human or live load the area may experience.
How is span measured?
It is commonly measured from the center of one support point, such as a wall, beam, purlin, or ridge to the center of the next support point. The span determines the location of structural supports and the size of the clear or unobstructed spaces in a building.
How long is a rafter span?
A look at a rafter span table shows the allowable spans are between 6’-7” and 23’-9”, depending on the factors and loads.
How far can a 2x8 span?
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.
