How to Set a Post for a Fence or Deck

Setting a post is the foundational step for many projects, including building a fence or a deck. Learn how to dig post holes and set 4x4 posts with gravel, concrete or foam.

Tools & materials:

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[earlm]

Filling the top portion of post hole with dirt will definitely ensure future fence work as posts are sure to rot! Job security at its finest.

[gutworm]

Always fill the concrete to above ground level and slope it away from the post. Never have a layer of soil around a post. It will only last a few years before it rots through and breaks.

[anonymousperson]

Simplest and easiest to understand deck post setting video that I have watched so far. Thanks Lowe's!!

[flores]

Forgot to said to call 811 before you dig . Don’t hit the electricity or Gas

[hownotto]

I demoed a deck recently that was build using method 3 on here. With the anchors.
I have demoed many decks before in my business, but the 22 year old deck was rotted from decking to joists, but underneath the joists I found the beams (2x10s) and 4x4 posts all in perfect shape with no rot. The posts had never come in contact with ground and all that wood was still reusable after 22 years.. tennessee is wet and humid where I live so decking is a constant replacement, but i will be using method 3 from now on for low load bearing decks.

[MikeE-hbzb]

30 years ago I built my first deck, my father in law helped me. We dug our holes 3 feet deep with post hole diggers, poured 6 inches of concrete in the bottom of the holes and waited 48 hrs! then we put the 4x4s in the hole on top of the crete and filled the rest of the hole with gravel (57s to be exact)... The deck is still standing it gets used everyday, the posts are not rotted.. We have replaced the railing over the years but, only by choice cause mom wanted it changed!! lol....I have since built a bunch of decks in the same way, to my knowledge all of them are doing fine today!!! Dont buy into this crap.. it takes a 4x4 a lifetime to rot!!!

[ordomaliosangeloseterna]

I heard flex seal works wonders if you spray the wood down to keep it from rotting.

[NoRoadsAllRoads]

if you have to dig no matter what I never get why people set with a method that is going to rot. Just fill the whole thing with concrete - 3rd option - and use a bracket. Even if it rots (much longer than any of the other options) or breaks, it's a matter of just replacing the post in like 5 minutes. Try replacing the post on the other 2 options.

[pedullabass]

I learned more from the comments than the video. After 24 years I sometimes have to replace the 4X4 treated post around my backyard fence that were put in by method 2. Post are rotting at the ground and breaking off. Im about to build a deck and dont want the same problem!

[johnvossler]

The cattle ranchers doing posts will always know better than city deck builders. I have several MILES of fence with all wooden posts, and mine is a smaller operation. No rancher has time or money for concrete, and the posts need to stand up to wind, snow etc. plus 1200 - 1800 pound cattle rubbing up against them all summer. Remember a good fence needs three qualities: 1) horse high, 2) dog tight, 3) Bull tough. You can do a great job without concrete and have it last many years. Mine are doing great and were installed new in 1994. I expect them to outlast me. Carry on!

[zoltanlakatos]

Here in Europe we do the option 3. It is much safer and the post is proteected by roting and moisture.We even secure the concrete from moisture by adding bitumen after it is hardened

[strokerace]

I just bought an 8 foot long 4x6 and dug two feet and put concrete around it, I didn’t want to have to cut the post!

[JohnB-ppdn]

I've recently started spraying auto undercoating on the portions of the post that contacts concrete, soils, stone, etc. That does stop the post from absorbing any moisture.

[scottwitkowski]

Buy a bucket of roofing tar. Seal the part of your post that will be in the ground and about 3 inches higher than the the ground level. Just worked on an old man's house who did that in 1989 and his post are still good. He does paint his deck regularly and has replaced some decking boards, but the deck is still safe and solid overall.

[AlMartins]

You may want to use the Fence Armor Rot Barrier to sleeve (Postsaver) the posts before they go into the ground to protect them from Rot. Then, above ground, the Fence Armor Post Guard to protect from lawn equipment damage.

[wrongfullyaccused]

The foam does not work. Within two days it shrinks away from the pole and the circumference of the hole. You end up with a loose post

[smsfffi]

Cheer~~a barrier, railing, or other upright structure, typically of wood or wire, enclosing an area of ground to mark a boundary, control access, or prevent escape.😊

[m_heavy]

Why would you use half a method to prevent rot then go and use the other half to make it rot?

[michaelsix]

mix concrete in wheelbarrow, then pour it in the hole, or you might get air pockets in it

[boke]

I live up north in sub zero temps and our freeze line is about 3.5 feet deep. I use the cardboard tubing (cut 4 feet, insert in hole and fill with cement) to place my posts. Why ? Because doing it like Mr. Lowe above seems to lift the cement base a few inches every darn Spring so that after 10 years a few of my old fence posts were almost a foot higher than the others. Replaced those with the cardboard tubing method....haven't risen an inch after 5 years.