#RAFTER LENGTH TABLE CODE#

Since some structural variables are localized, it’s best to check your local code for allowable spans.Ī general rule of thumb for joist span is 1-1/2 times a board’s depth in feet, however, it’s not that simple. The allowable distances it can span without support are identified in National, State, Provincial, and Local Building Codes. How Far Can a 2×6 Span Without Support?Ī 2×6 can be used for floors, walls, ceilings, roofs, and other facets of construction. Hockey arenas, gymnasiums, and airplane hangars are examples of long span construction. This provides larger unobstructed spaces or rooms.

#RAFTER LENGTH TABLE FREE#

Plus, there is the free span or long span that commonly refers to structures without intermediate internal supports, so all loads are carried on exterior walls. The clear span is the space between adjacent support faces. To add to the confusion, there is the effective span which is measured from the center of one support to the center of the next support. Rafters span greater distances from support center to support center, but the horizontal distance from centerline to centerline is often the same as that of a joist. Loads limit joists to shorter spans than rafters of the same grade and species. The span differs, however, if it is horizontal like a joist or beam, or diagonal for rafters. It is measured from the center of one support to the center of the next. Span, in construction, means the distance a structural member traverses from support to support. There are many terms that have different meanings, and span is one such word. Span Definition – What Does Span Mean in Construction? How Far Can You Span a 2×6 Ceiling Joist?.How Far Can a 2×6 Span Without Support?.Span Definition – What Does Span Mean in Construction?.Additionally, we’ll explain 2×6 decking and deck joist spans, 2 and 3 ply deck beam spans, and header spans so you have the information needed for your 2×6 building projects.

We’ll also explore how far a 2×6 can reach as a floor or ceiling joist, and as a rafter. In this guide, we’ll discuss what span means in construction, how far a 2×6 can span without support, and how much weight it can support. Always check the codes for determining factors or consult a Structural Engineer.

The maximum distance a 2×6 can span, according to the 2018 IRC, for a floor joist, is 12’-6”, ceiling joist 20’-8”, rafter 18’-0”, deck board 24”, deck joist 9’-11”, deck beam 8’-3”, and 6’-1” as for header. If you’re finding this confusing, we’re here to help.

If you’re planning to use 2圆s for joists, rafters, decking, beams, or headers, you’re probably wondering how far can a 2×6 span without support? Span depends on wood species and grade, use, spacing between members, and potential loads. (I sleep well that way.Selecting lumber for different projects can be difficult even for the pros. You never know when the client will call and want to add an air conditioner on the roof, or they’re going to invite you to their 50th anniversary out on their deck. I like a very safe size rather than figuring everything too tight. Ultimate stress design figures exactly when the beam will fail and then uses an allowable safety factor.sometimes 1.5, or 1.8%. Working stress leaves a BIG safety factor because they know a home owner will be using it. That’s why carpenters like to hand pick beams, (they know they have an extra safety factor so the beams won’t twist, Bend, etc.)īeams are calculated using the “working stress design” or “ultimate stress design”. Grade of beam can be upgraded if more of the beam (edges of beam) can be observed during grading. Wood is somewhat elastic, so it depends on how many allowable factors you care to investigate to determine its maximum span.Įven the same grade and species can have its “allowable stresses” increased based on “duration of load.” That is to say that if you put a heavy short duration load on a beam it will act the same as a smaller long term load. There’s lots of factors that determine the size of wood beams.

Rafter length table