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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 I use 4×4 or 4×6 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.
Can I use 4×4 posts for my 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.
How tall can a 6×6 post be?
Recommended Maximum Heights The AFPA recommends that six-by-six posts be no taller than 14 feet, regardless of the tributary load they’re required to carry.
How far apart should 4×4 posts be on a deck?
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 deck posts be 4×4 or 6×6?
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.
How much weight will a 4×4 post support?
4×4 can hold up to 4,000 pounds when laying horizontally with the right support. Vertically, a 4×4 should support 4300 pounds but can hold significantly more. The amount of weight that a 4×4 can hold depends on several factors like wood grade, species, and load type.
How far apart should posts be for a deck?
Layout and Footing Locations Starting with your perimeter, mark the location of each deck post to locate the fitting position. In general, posts should be spaced no more than 8 feet apart. Some builders position them every 4 feet for a completely rigid frame.
How deep should deck posts be set?
Set footers a minimum of 6” below the frost line for your area to prevent movement during freezing temperatures. Pour about 6 inches of all-purpose gravel into postholes and pack the gravel tight by using the end of a wooden post.
Is a 4×4 post stronger than 2 2x4s?
When used vertically, 4x4s are stronger than two 2x4s. However, if you need a horizontal surface, two 2x4s will be stronger than one 4×4. A 4×4 should not be used horizontally for anything structural. Always be sure that you’re using the proper size and strength of lumber.
What accounts for roughly 90% of all deck collapses?
About 90% of deck collapses occurred as a result of the separation of the deck ledger board from the house, allowing the deck to swing away from the house. It is very rare for deck floor joists to break mid-span. Many more injuries are the result of rail failure, rather than complete deck collapse.
How much weight can a 8×8 post hold?
That being said, a post can hold a tremendous amount of load! If a particular species of wood can support 1,000 psi, then an 8×8 post can hold 64,000 pounds! The limiting factor (reason to up-size) will likely be aesthetics and/or the number or type of joints needed.
How Tall Can decks be?
When Is a Deck Guardrail Not Needed? Some decks are not required to have guardrails, provided those decks are no more than 30 inches above grade. If you see a deck that has no guardrails (also called a low-rise deck), this might be the reason: its height is below 30 inches.
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 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.
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.
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.
Should you notch deck posts?
Say “No” to notching pressure-treated deck posts. We want you to build an outdoor railing system that you, your family and guests can enjoy without worrying about safety issues. In order to do so, you need to know this building shortcut is not advisable, and we recommend avoiding it at all costs.
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.
