How far can you span a 2×8 roof rafter?

Max. Live Load 60 lbs/ft2 (2873 N/m2)

Maximum Span (ft – in)
Nominal Size (inches) Joist Spacing Center to Center, OC (inches) Lumber Grade
2 x 8 12 12′ – 3”
16 11′
24 9′

How far can you span a 2×6 for a roof?

What is this? A 2×6 rafter can span 14 feet 8 inches when spaced 16 inches apart with No. 1-grade southern pine lumber on a roof with a 3/12 slope or less with a maximum live load of 20 pounds per square foot and a dead load of 15 psf.

Can you use 2×6 for roof rafters?

2×6 shed roof rafters are enough for nearly any type of shed a homeowner wants to build. While a 2×6 might be nearly double the cost of a 2×4, you can likely space the 2x6s further apart, negating the added expense of increasing your lumber width. An SYP 2×6 rafter at 24 O.C. can span up to 13’4”.

What size should rafters be?

Use these two tables for roof rafters with a slope greater than 3″ in 12″.

Nominal Size Spaced (o.c.) Species / Grade ( 40# Live Load – Heavy Roofing)
2″ x 4″ 12 7-8
16 6-8
24 5-5
2″ x 6″ 12 11-4

How far can a 2×4 Rafter span without support?

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. Due to the small spans of 2x4s, they often are not used in horizontal load-bearing capacities.

How far can a double 2×8 span without support?

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 what span means in terms of construction, factors that impact the span, and how much weight a 2×8 can support.

How far can a 2×4 span without support?

2×4 is suitable when the range is less than 5 feet. If the span was 4 or 5 feet (maximum) before being supported by a joist, a 2×4 should be fine.

How far can a 2×4 rafter span without support?

What span can a 2×4 support?

According to the American Wood Council, Douglas Fir 2x4s spaced 24 inches apart can handle a maximum span of 6 feet 6 inches. In comparison, Sitka Spruce is slightly stronger with a maximum span of 6 feet 8 inches.

Are two 2X6 stronger than a 2×8?

In bending, a joist composed of two 2×6’s (true dimension 1.5 inches x 5.5 inches) are slightly stronger than a single 2×8 true dimensions 1.5 inches by 7.25 inches.