How far can a rafter span without support?
A 2×6 spaced 16 inches apart can span a maximum distance of 13 feet 5 inches when used as a rafter, 10 feet 9 inches when used as a joist, and 6 feet 11 inches when used as a deck beam to support joists with a 6-foot span.
How wide can rafters span?
For example, 2-by-6 rafters made from select structural grade Douglas fir that are required to support a live load of 20 pounds per square inch can have a maximum horizontal span of 11 feet 4 inches. Decreasing the distance between rafters to 12 inches, however, increases the maximum span to 14 feet 4 inches.
How far can a 2×6 span for ceiling joists?
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. Always check the codes for determining factors or consult a Structural Engineer.
Can a 2×6 span 8 feet?
A 2×6 joist can span anywhere between 8′ for Cedar and Redwood to 9′ for Pine and Fir at 16″ OC. 12″ OC yields longer spans, while 24″ OC allows shorter spans.
What size rafters do I need for a 16 foot span?
Max. Live Load 20 lbs/ft2 (956 N/m2)
| Maximum Span (ft – in) | ||
|---|---|---|
| Nominal Size (inches) | Rafter Spacing, Center to Center, OC (inches) | Lumber Grade |
| 2 x 6 | 16 | 14′ – 11” |
| 24 | 13′ | |
| 2 x 8 | 12 | 21′ – 7” |
What is the maximum span for a 2×4 Rafter?
Spacing your 2×4 shed rafters at 24” on center limits the width of your roof. For light load roofs, 24” o.c. 2×4 rafters can span up to 7 ⅔’. For heavy loads, 2x4s can span up to 5 ½’.
Are 2×6 strong enough for deck joists?
For upper-level decks, 2×10 is recommended as the minimum size to use for strong guard post connections. 2×6 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″.
How far can a 2×12 Rafter span without support?
Max. Live Load 20 lbs/ft2 (956 N/m2)
| Maximum Span (ft – in) | ||
|---|---|---|
| Nominal Size (inches) | Rafter Spacing, Center to Center, OC (inches) | Lumber Grade |
| 2 x 12 | 12 | 26′ – 5” |
| 16 | 22′ – 10” | |
| 24 | 18′ – 8” |
How far can a 4X8 beam span without support?
Dimensional Lumber Deck Beam Span Chart
| Joist Spans | ||
|---|---|---|
| Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir, Redwood, Cedars, Ponderosa Pine, Red Pine | 4X6 | 6′-2″ |
| 4X8 | 8′-2″ | |
| 4X10 | 9′-8″ | |
| 4X12 | 11′-2″ |
How far can a 2×4 span without sagging?
An interior 2×4 beam – made up of two 2x4s nailed together – can span up to 3′ 1” without support beneath a set of joists for a home no greater than 20′ wide and supporting no more than 1 floor. For homes that are 28′ wide, a double 2×4 can support a span of 2′ 8”.
Can a rafter be extended beyond the supporting wall?
Rafter spans can be extended slightly beyond what the rafter tables suggest, when there is a cantelever extending beyond the supporting wall. Use this table to determine the maximum lengths of ceiling joists based on species of lumber, joist spacing, and joist size.
How to determine the length of a roof rafter?
Rafter span tables – Use these tables to determine lengths, sizes and spacing of rafters based on a variety of factors such as, species, load, grade, spacing and pitch. Visit the roof framing page for more information on cutting roof rafters, and visit the roof pitch calculator for determining rafter lengths based on rise and run.
What’s the maximum span of a yellow pine rafter?
For example, in the rafter span table below, the highlighted cell (in the 40# Live Load table), indicates that 2″ x 8″ Southern Yellow Pine joists, that have a grade of #2, that are spaced 24″ apart, can have a maximum span of 10 feet – 3 inches (10-3) if designing for a live load of 40 lbs/ft2.
How tall is a 2 x 6 Rafter in feet?
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.