How far apart should deck support posts be?

8 feet
In general, posts should be spaced no more than 8 feet apart. Some builders position them every 4 feet for a completely rigid frame. The maximum distance between footings is determined by the size of your joist material.

How many support beams do I need for a deck?

For a deck that is 15 feet wide with 2×10 joists spaced at 16 inches apart, you have two options. You can use two beams, one at 7.5 feet and one at 15 feet, to provide support.

How many supports 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. Using doubled boards, you will then need to build beams on the top row of the posts to frame the edges of the deck. These must be topped with adjustable post caps.

How often do you need posts for a deck?

Distance Between Deck Posts

Any deck that is 8-by-12 or larger will need a post installed at each of the corners. A line post needs to be placed between each pair of corner posts.

Can I 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.

What size post should I use for a deck?

Deck posts must be a minimum of 4×4 according to the IRC but many jurisdictions require a 6×6 post as a standard. To avoid code violations, many deck builders choose the 6×6 even if the 4×4 is acceptable.

Should you use 4×4 or 6×6 deck posts?

While there may be a handful of circumstances that only require the minimum 4×4 deck post, you will more than likely want to choose a 6×6 post for the deck. It provides more stability for larger decks, the ability to hold a heavier load, and more room for notching.

How do I support my deck posts?

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

For an attached 12 x 12′ deck, you’ll need at least 3 footings, plus at least 2 more if you’re planning on building stairs with it.

Should deck joists be 2×6 or 2×8?

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″.

How far apart should 6×6 deck posts be?

8 feet
For Building a Deck Railing, Deck Frame, or Fence

The maximum spacing of 4×4 deck posts should be 6 feet on center, while the maximum spacing of 6×6 deck posts should be 8 feet on center.

Should I set my deck posts in concrete?

A deck post should always be placed on top of footing, not inside concrete because it can break. … Concrete tends to absorb moisture and wood expands when it gets wet, so these two factors combined will result in the wood breaking the concrete.

How many joists do I need for a 12×12 deck?

10 joists
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.

How far can a 2×8 span for a deck?

Using this rule, a 2×6 will span 9 feet, a 2×8 will span 12 feet, and a 2×10 will span 15 feet. As you can see, the larger the depth, the longer the span.

Can I use 2×8 for deck boards?

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.

How many posts do I need for a 10×10 deck?

A freestanding 10′ x10′ deck needs 4 posts, supporting two pairs of 2-ply non-incised 2×8 beam, upgrading the beam to 3-ply using incised wood.

Can I use 4×4 for deck joists?

For most decks, 4×4 lumber is strong enough for structural posts. If a deck is raised more than 6 feet above the ground, codes may require 6×6 posts.

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.

Can I use 4×4 posts for a deck?

In the past, many decks were built with 4×4 support posts (also called structural posts). But these can bow seriously, even if a deck is only 3 feet off the ground. For that reason, we strongly recommend that you use 6x6s instead, even if your building department does not demand them.

What is the average cost of a 12×12 deck?

A 12 x12 deck can range in cost from $2 200 to $13 000, but the average will be $6 000. Costing $40 a square foot but can be as little as $15 or as high as $85, depending on the deck’s features. A pressure treated deck is the most economical, with composite being the more expansive option.

How do you calculate deck posts?

Draw a line through the mid-span of the joists. Then find the mid-span of the beam that the post supports, and extend lines from there back to the line at the joist mid-span. Find the area within the lines. To calculate the design load for the post, multiply the tributary area by the combined live and deceased loads.

Which is stronger 4×4 or 2×6?

The single 2×6 is 68% stronger than the 4×4 for vertical loads as you describe. However, I caution you that it may be a good idea to have someone design this beam properly so the job is done right. If you’re willing to have a 4″ wide beam, why not create a double 2×6 beam, this will be 237% stronger!

How much weight will a 4×6 post support?

2 Answers. Assuming it’s “Lodgepole Pine” (Idaho Pine and Ponderosa Pine is slightly less) and it’s grade is a No. 2 and better (no loose or missing knotholes), then a 4×6 spanning 18′ will support about 105 lbs.

How thick should deck posts be?

Assuming a minimum soil bearing capacity of 1,500 psf, 8-inch-diameter concrete piers bearing on square footings measuring 2 feet on a side and 9 to 11 inches thick are adequate for most single-story decks where beams are spaced 14 feet apart or less and joist spans are 14 feet or less (see table below).