Next, pour an additional three inches of gravel into the hole, tamping down a second time. This simple measure goes a long way toward helping rainwater drain freely into the subsoil. It works so well, in fact, that in mild climates, builders sometimes elect to set fence posts with gravel alone.
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. Then compact and level the gravel using a post or 2x4.
Fill with Gravel or Concrete
The choice is yours. Gravel helps keep moisture from the fence posts, slowing the rot. Concrete can more sturdily set the posts, but the moisture in the concrete may collect and absorb at the bottom of the post, accelerating the very process you're trying to mitigate.
Once you've dug your hole, place about 6 inches of aggregate in the bottom of the posthole to allow for drainage. This will minimize the amount of water that comes into contact with your cedar fence post. Pro Tip: The bottom of the post should extend a few inches into the aggregate as shown.
If there are more than one rock or stone or if there are a series at regular intervals, rocks were used to indicate a turning or stopping point. Long before marking chalk, paint, strip markers and GPS were available, ranchers and farmers used stones as visible place or reference point markers.
The answer -— as it often does in fencing construction — depends. As a general rule, Fencing Direct recommends at least a 24-inch footing depth for a 4-foot fence, plus an extra 3 inches for every foot of height (for example, 27 inches for a 5-foot post).
Take a shovel and dig a hole roughly 10 inches beneath where the fence post will stand. Fill the hole in with gravel, this will help to support the post, as well as creating adequate drainage for water to pass through.
How long will 4x4 post last in the ground? A pressure treated 4x4 set in concrete should last about 20 years of more, depending on the soil conditions and drainage.
Purchase a wood preservative that contains copper naphthenate at a lumberyard or hardware store. Pour about 1⁄2 litre (0.53 qt) of it into a large bucket. Set the end of your post that you'll bury in the ground into the bucket and let it soak for 15–20 minutes.
Most fence posts require anywhere from one to 10 bags of concrete. Actual concrete amounts vary depending on post hole diameter and depth. Account for frost lines and gravel when doing calculations.
You can apply it to your wood to prevent rotting. But you can also use it to stop an active infection. After the fungi have been killed, you can apply pine tar wood to add an extra layer of protection to the wood. It even stops any moisture from seeping into the wood causing it to rot.
Pea Gravel. Pea gravel is one of the best materials for landscape drainage because its small size allows for outstanding drainage.
As a general rule of thumb, you'll need to place at least 1/3 the height of the post in the ground. For example, a six-foot tall fence will need at least two feet of post in the ground.
Stabilize Your Fence Post
You'll first want to dig a few inches of soil out from around the post's perimeter. From there, you can fill the hole with gravel and top the gravel with a rapid-set cement mix. Finally, pound the fence post back into place using a mallet.
In most applications, a wooden fence should be mounted at least two inches off the ground. Your posts and rot boards (if you want to mount them) should be the only fence components that come into contact with the ground. Wood pickets are never meant to touch it.
Back in 1961, two wood scientists planted treated-lumber posts in the ground of southern Mississippi. Sixty years later, most of those posts are still there—no rot, no fungi, no termites. Their experiment set the official statistical lifespan of treated lumber that the industry refers to today: over 60 years.
While cedar's tight grain, resistance to rot, and lack of knots make for optimal fence material – it is less durable against soil than pressure treated pine (in posts). For this reason, it may be a good idea to use pressure treated pine for the posts and cedar for the rest of the fence.
Your deck will not pass inspection with inadequate footings and the posts can be forced up by frost when the ground freezes, known as “heaving” which can destroy it. Dig each footing 48 inches deep and 10 to 12 inches across, centered on the location you marked when laying out your deck.
Use pressure treated wood in any situation where there's direct contact between the wood and anything that could supply moisture. This means posts in contact or buried underground obviously, but it also includes any lumber touching concrete or masonry since it's porous and wicks water like a sponge.
One of the most important reasons your fence posts should be set in concrete is to keep them plumb and level over time. If all supporting the fence post is loose soil or sand, a good storm with heavy rains and strong winds can leave your fence leaning and posts sagging.
Mix two 50lb bags of concrete with water in a mixing tub or 5-gallon bucket. Add concrete into the hole and around the 4” x 4”. Depending on your climate, let concrete set up for 24 - 48 hours.