How far apart should beams be on a deck?

16″





Most decks use 16″ on center spacing for joists. Most decking is not strong enough to support wider spans than 16″. Some builders reduce joist spacing to 12″ on center to strengthen the deck frame or to increase maximum allowable joist spans.

How big should deck joists be?

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.

How far should you space joists?

Floor joists are typically 12”, 16”, or 24” apart in a home. Most common spacing for floor joists is 16” o.c. You’ll notice that the joist span tables also include 19.2” on center as an option. This spacing is typically for I-beam and truss joists since the tops of those types of joists are wider.

What is the maximum span for deck joists?

Depending on the size of the deck itself, whether your joists are spaced either 12 inches or 16 inches from the center, and the framing materials and size of deck boards used, deck joist spans may vary. With this in mind, the joist span can range between 6 ft, 10 inches, to 18 ft.

What size beam do I need for a 12 foot span?





Thus, for a 12 foot span, you will need atleast 3-2×10 or 6×10 size of wood beam. For a 12-foot spans, the wood beam has to be at least 10 inches in depth and 6″ in width (3-2×10) used for residential building, wood frame structure or projects.

Can I use 2X6 for deck beams?

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).

How many joists do I need for a 10×12 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.

What size bearers and joists for a deck?

The bearers have to carry the weight of the entire deck and whatever is put on top of it, so they need to be strong. A 140×45 treated pine bearer will usually do the trick. Every 1.2 metres, a 90×90 H4 treated pine post will be needed. Treated pine is the easiest to work with.

How far can a 2×6 joist span on a deck?



How Far Can 2×6 Decking Span? A decking board made up of 2x6s can span a maximum distance of 24 inches from joist to joist.

Do deck joists need blocking?

According to National Design Specifications (NDS) blocking is required on any deck joist over 8ft long on 2″x 10″ and 2″ x 12″ material. We would recommend blocking on any deck joists greater than 2″ x 6″.

What size beam do I need for a 14 foot span?

Thus, for a 14 foot span, you will need atleast 3-2×12 or 6×12 size of wood beam. For a 14-foot spans, the wood beam has to be at least 12 inches in depth and 6″ in width (3-2×12) used for residential building, wood frame structure or projects.

How big of a beam do I need to span 20 feet?



What size beam to span 20 ft:- as per general thumb rule and guidelines, a 4 nailed 2×16 or 4-2×16 or 8×16 size of wood beam can allow to span 20 ft. Thus, for a 20 foot span, you will need atleast 4-2×16 or 8×16 size of wood beam.

How far can a beam span without support?

Some manufacturers limit their beams to 60′ due to transportation issues, while others have the capability to manufacture beams up to 80′ long. So, the longest unsupported span possible using LVL would be 80-feet. Typically, though, it is common for a continuous LVL span to be between 20′ and 30′.

Can I use a 6×6 as a deck beam?

Just one 6×6 would almost certainly not meet code or load table requirements, resulting in sag and a safety concern.

What size beam do I need to span 24 feet?

What size beam to span 24 ft:- as per general thumb rule and guidelines, a 4 nailed 2×18 or 4-2×18 or 8×18 size of wood beam can allow to span 24 feet. Thus, for a 24 foot span, you will need atleast 4-2×18 or 8×18 size of wood beam.

How long can wood beams go 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.

How far can a 2X10 deck beam span?

Dimensional Lumber Deck Beam Span Chart

Joist Spans
Southern Pine 3-2X10 7′-3″
3-2X12 8′-7″
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir, Redwood, Cedars, Ponderosa Pine, Red Pine 3X6 OR 2-2X6 2′-6″
3X8 OR 2-2X8 3′-5″

How do I know what size beam I need?

Design a beam depth based on the rule of thumb for estimating the depth of manufactured beams which is to divide the span by 20. Beam depths are typically 5 1/2 inches, 7 1/4 inches, 9 1/4 inches, 11 1/4 inches, 11 7/8 inches, 14 inches, 16 inches, 18 inches, and 20 inches.