QA

What Size Floor Joists For Deck

Commonly used joist sizes are 2-by-6, 2-by-8 and 2-by-10. For example, when you space joists 16″ apart — which is standard for residential decks — a deck spanning 9 1/2′ would require 2-by-6 joists, a 13′ deck would need 2-by-8 joists and a 16′ deck calls for 2-by-10 joists.

Should I use 2×6 or 2×8 for deck?

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″.

Can I use 2×8 for deck joists?

2×8 for joists will be fine, with 16″ OC. Should use 2×10 for beams but 2×8 will be fine as well. If you are worried you can triple the 2×8 for the beams but double will be sufficient. You should put the beams at 7 and 14 feet out from the house, with the piers you should do 3 per beam with spacing of 1, 7, 13.

How far can 2×6 deck joist span?

2-grade 2×6 joists can span up to 10 feet 9 inches from beam to beam when spaced the standard 16 inches apart with a maximum live load of 30 inches per square foot.

What size joist do I need for a 12×12 deck?

For example, a 12-foot x 12-foot deck of 5/4 x 6 pressure treated wood decking on 16 inches on center spacing of joists will require: A 12-foot long deck with joists 16 inches on center will require 10 joists. 20 fasteners x 26 (number of rows of decking) = 520 fasteners. Add 10 percent to be safe.

How far can a 2×8 span for a deck?

Depending on various factors, the maximum span for a 2×8 floor joist is 16′ 6”. The maximum span for roof rafters is 23′ 9”. For headers, the maximum span is 11′ 2”. Finally, a single deck beam has a maximum span of 5′ 11” and double maxes out at 8′ 9”.

Are 2×6 strong enough for floor joists?

2 Answers. 2×6 joists at the span that you are talking about (16′ and 18′) are not strong enough to support a floor as a living space. With a span like that the timber size that you sister in would have to be at least 2×10’s.

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

A 2×10 beam – made up of two 2x10s nailed together – can span up to 11′ without support beneath a deck that is 4′ wide. For a more normal-sized deck, the same beam can span 8′, supporting a deck that is 8′ wide. You can also triple a 2×10 beam.

How far can a 2×8 span without support?

Based on different manufacturers’ specifications, the maximum span a 2×8 LVL is from 12′ to 15′. Spans are also affected by the species of wood used in the manufacture of the laminated joists, with western woods edging out eastern woods in unsupported span distance.

Should I use 2×4 or 2×6 for deck?

Most builders stick to using a minimum of 2x6s for deck floor joists. If you want to add guardrails and stairs, you need at least 2x10s. 2×4 and 2×6 joists are ideal for ground-level decks without guards.

Can I use 2×6 for deck frame?

Or are 2x6s to small for deck joists? You can use 2×6 as deck joists if the deck is low enough to the ground as not to require guard railing. When using S-P-F 2×6 deck joists, the span must not be greater than 9’0″ (2.73m) with joists at 16″ o.c. (400mm), and 9’10” (3.01m)with spacing at 12″ (300mm).

Can I use 2×6 for deck boards?

Wood decking is commonly available in 2×6 and 5/4 x 6 profiles. 5/4 x 6 is produced specifically for decking and is milled with a radius edge or bull nose. 2×6 is thicker and is stronger, but is also more expensive. Spacing between deck boards provide a few critical functions.

Can you use 4×2 for decking frame?

4 x 2 Timber Rail / Joist. These decking joists are the most common sized framing timber for decking. They provide a solid structure for fixing your decking boards too. When making your decking frame you should use a 400mm spacing between your timber joists.

How many posts do I need for a 12×16 deck?

A standard deck will need four footings parallel to the house, but they will need to be temporarily braced by 6 inch-by-6 inch posts.

How far can a 2×12 floor joist span without support?

As the table shows, no 2×8’s meet the span and spacing requirements, but a 2×10 with an E of 1,300,000 psi and Fb of 1093 psi can span 15 feet 3 inches – more than enough. A 2×12 with an E of 800,000 psi and Fb of 790 psi also works, since it can span 15 feet and 10 inches.

How many Trex boards do I need for a 12×12 deck?

(Choose from 8, 12, 16, or 20 ft board lengths. Choose which board best fits the dimensions of the deck.Decking Materials. Board length Boards required 8 FT 206 12 FT 137 16 FT 103 20 FT 83.

How many joists do I need for a 16 foot deck?

For example, when you space joists 16″ apart — which is standard for residential decks — a deck spanning 9 1/2′ would require 2-by-6 joists, a 13′ deck would need 2-by-8 joists and a 16′ deck calls for 2-by-10 joists.

What size should floor joists be?

Typical Floor Joist Size In Residential Construction Floor joists range from 2×8 to 2×12. It is less common to see joists that are 2×6, even though they are included in joist span tables. Older homes are more likely to use 2×6 for joist framing.