Q: Can I use 2×8 treated lumber as deck boards? A: No, that’s a not a good idea. Lumber wider than 6 inches should not be used as a flat surface. Wide, flat boards have a tendency to pool rain water, which can lead to cupping problems.

There is certainly no problem **using** the 2x10s for any of the structural framing of the **deck**. **Using 2×10** treated **lumber** for **decking** is another matter entirely. **I would** not recommend them for **decking**. The larger the growth rings the more unstable the **lumber** is.

Subsequently, question is, how much weight can a 2×8 support? some of it gets pretty technical in nature, and mostly relates to pounds / square foot of loading. 2x6s are generally used for ceiling joists, esp since you said 24″ oc and reallllly short spans only (5 or 6 feet ). Most floor loads would be a minimum of **2×8** @ 16″ oc and most preferbaly 2×10.

In this regard, what size deck boards should I use?

Joists spaced 16 inches on center will **take** both 5/4 and 2-inch **deck boards** (which are actually 1-1/2 inches thick). However, if your joists are spaced 24 inches on center, or if you plan to lay the **deck boards** on a diagonal, building codes typically require 2-inch material.

Should I use deck boards or 2×6?

**2×6** is thicker and is stronger, but is also more expensive. Spacing between **deck boards** provide a few critical functions. The primary function is to drain water from the **deck**. Overall, conventional decking profiles **should** be installed such that when seasoned, will have gaps between 1/8 and 1/4 of an inch.

### What size lumber can span 20 feet?

Re: 20 foot clearspan beam size In that case, you need something like a 12-16″ GLULAM or LVL to span the 20′ and can use simple 2×8-10 dimensional lumber 16″OC as floor joists.

### How far can a 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.

### How far can a 2×10 span without support?

When supporting joists that span 12 feet with no overhang beyond the beam, a double ply beam can span in feet a value equal to its depth in inches. A double 2×12 beam can span 12 feet; a (2) 2×10 can span 10 feet and so on.

### How far can 2×6 decking span?

Decking boards span from joist to joist. If you use 5/4 decking, joists must be no farther apart than 16 inches. Decking made of 2x4s or 2x6s can span up to 24 inches.

### How far can a 2×6 Rafter span without support?

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.

### How much weight can a 2×10 hold?

1,200 lbs

### How far can you cantilever a 2×8 joist?

If the code span tables allow a 2×8 to span 12 feet, then the cantilever can be 3 feet.

### How far can you span a 2×6 ceiling joist?

Joist spacing of 24 inches is allowed for spans between 16 to 20 feet using 2-inch by 10-inch lumber of these three grades.

### Should you countersink deck screws?

If you are face-driving deck screws, it is acceptable to “self-countersink” them. Some deck screws even have a little cutter head built into the screw, to facilitate countersinking.

### Should deck boards have a gap?

The goal is to have about an 1/8-inch gap (the diameter of an 8d nail) between boards after the decking has dried to its equilibrium moisture content. If the decking is installed wet, as is often the case for pressure treated material, it is best to install the boards tight, letting gaps form as the wood dries.

### What is the spacing between deck boards?

A gap of 10mm between deck boards and external walls of adjacent buildings is recommended for drainage. Board spacing depends on the width of the board but a guide is 3-4mm for 90mm boards and 5-6mm for 140mm boards. Note that if wet decking boards are laid, when they dry out the gaps between them will increase.

### Can you use 1×6 for deck boards?

For Kiln Dried decking set spacing between boards at 3/16” for 4” and 1/4” for 6” decking. Generally, 1×4 and 1×6 decking can be installed with joists on 16” centers. 5/4×4 and 5/4×6 decking can be installed with joists on 24” centers. When installing on an angle, joist spacing should be on 12” centers.

### Should I use 2×4 or 2×6 for deck?

2x4s are never ok for floor joists! 2×6 is iffy and may not meet minimum code. I agree with Marksr, that 2×6 would be minimal. Use a 4×6 rather than 2-2×6’s for your beam.