How deep should 4x4 deck posts be?

Dig post hole so diameter of the hole is 3 times the width of the post (i.e., the hole for a 4” wood post should be about 12 inches wide). The depth of the hole should be 1/3-1/2 the post height above ground (i.e., a 6-foot tall fence would require a hole depth of at least 2 feet).

How deep should a decking post be?

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.

How big of a footing do I need for a 4x4 post?

FOOTINGS: - Poured concrete footings should be a minimum of 8” wider than the posts (4x4 post – 12” min. width, 6x6 post – 14” min. width), a two level deck or deck with roof – 24”x24”. - The bottom of the footings must be a minimum of 36” below finish grade level.

How deep should a concrete be for a 4x4 post?

So, if you're planning on using a four-inch round or 4x4-inch square post, your post hole will need to be 12 inches in diameter. For our six-foot-high fence post, we would need a hole that's 36 inches deep and 12 inches in diameter. The depth of your post hole plays a key role in the strength of your posts.

How deep do you have to dig for deck posts?

Dig the holes six inches deeper than the required frost line depth for your area, and slightly wider than the concrete footer tubes you'll be using.

How to Set a Post for a Fence or Deck

Should deck post be set in concrete?

A deck post should always be placed on top of footing, not inside concrete because it can break. The photo on the left shows a post set in a bracket that has been mounted to the top of a footer. The photo on the right shows a post that has concrete poured around it, which can lead to a crack like you see here.

How deep should an 8 foot post be in the ground?

For an average fence post, about 6 to 8 feet tall, prepare to dig a post hole about 2 feet deep. To install a fence post, you'll need a shovel or post digger, a 6-foot level, soil, and gravel or crushed stone.

Can I use 4x4 for deck posts?

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.

Does a deck footing need rebar?

Plain concrete deck foundations without rebar are acceptable under the minimum standards of construction established in the International Residential Code. However, placing reinforcing steel within footings is a relatively easy and inexpensive practice that can provide increased performance.

How deep should a footer be for a support post?

Depth of Footings

Footings should extend to a minimum depth of 12 inches below previously undisturbed soil. Footings also must extend at least 12 inches below the frost line (the depth to which the ground freezes in winter) or must be frost-protected.

How big should the hole be for a deck post?

Dig an 8"-diameter hole at least 6" deeper than your area's frost line for each 4x4 post, using a power auger, hand auger, or post-hole digger. A 6x6 post requires a 10"-diameter hole. Shovel a 6" layer of gravel into the hole to provide drainage.

How deep should a 6x6 post be in the ground for a deck?

The depth of the hole should be 1/3-1/2 the post height above ground (i.e., a 6-foot tall fence would require a hole depth of at least 2 feet). Add about 6 inches of QUIKRETE All-Purpose Gravel into the bottom of the hole.

What size sonotube for a 4x4 post?

What size Sonotube do I need for a 4x4” fence post? The rule-of-thumb is to use a tube diameter 3 times the post width, therefore use a 12” diameter Sonotube for a 4x4” post.

How much concrete is needed for a post hole?

A: Finding the right amount of concrete depends on the size of the hole and the size of the post. The diameter of the hole should equal about three times the diameter of the post and the depth of the hole should be about ⅓ to ½ the total length of the pole.

How do I put a post in the ground without concrete?

Will pressure-treated wood rot in concrete?

Simply setting the posts in concrete does create a condition that will accelerate rot in the bottom of the posts. With pressure-treated posts, the rot will be slow.

Can pressure-treated wood be buried?

Yes. Pressure-treated wood can be buried in the dirt when used as a fence post or any exterior structure that requires underground support. However, it needs the most protection because continuous exposure to moisture in the dirt might cause the wood to rot and waste away prematurely.