# How far can a 2×8 span with support?

## How far can a 2×8 span with 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 2×8 span without support?**

In general terms, joists spaced 16 inches on center can span 1.5 times in feet their depth in inches. A 2×8 up to 12 feet; 2×10 to 15 feet and 2×12 to 18 feet. The larger the deck, the larger the joists.

**Can 2×8 be used for floor joist?**

From what you said in your posts, that would mean the room with the 2 x 8 floor joists has a joist span of 12′. The room is 24′ long and 12′ wide with a steel beam running down the middle of the width which halves the 24′ span to 12′. 2 x 8’s are maximum spanned at 12′ long spaced 16″ oc.

### How far can you cantilever a 2×8?

A Wood Council document (here) gives some very high-end detail about decks, but the take-away as far as cantilevers go is almost exactly the same: 400mm/16” for 2×6 or 2×8 lumber, and 600mm/24” for 2×10 or 2×12 lumber.

**How far can a 2×10 header span without support?**

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.

**Can I sister a 2×8 with a 2×6?**

OR can we add 2X8s next to the 2×6’s It is an upstairs bedroom..— Yes, you can sister 2×8’s to 2×6’s and keep the 2×8 rating for a longer span.

## How big of a load can a 2×8 support?

A 2×8 will support a dead load of 20psf and a live load of 40psf resulting in a total load of 60psf. Depending on the species, grade, and spacing, a 2×8 may span between 7’-1” and 15’-0”. The strength of a board is inversely proportional to the span – the greater the span, the less weight the plank will support.

**What is the maximum span for a 2×8 floor joist?**

Most floor loads would be a minimum of 2×8 @ 16″ oc and most preferbaly 2×10. How long can floor joists be without support? A live load of 60 pounds per square foot demands more support and shorter spans.

**How big can a 2×8 deck be without support?**

To strengthen a floor or deck area or extend the span, a common practice is to sister or double the joists. Doubled 2x8s will span about 25% further than single joists with the same spacing. For a #3 SPF, that isn’t much, 1’-9” added to the maximum span, whereas doubling an SS Douglas fir-larch adds 4’-1” to the maximum span.

### How many beam spans do you need for a 2×8 beam?

These nine beam spans are for built-up beams made up of either 2X8, 2X10 or 2X12 dimensional lumber nailed together as either 3, 4, or 5 ply beams. For example a 3-ply 2X8 beam would use three 2X8s nailed together side by side.