Can you fill vinyl fence post with concrete

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The short answer is yes, you can fill vinyl fence posts with concrete but not successful if you don’t know the right process. If you’ve ever tried to fill in one of these posts with concrete by just dumping the bucket on it and tamping it down, you know what I mean. The posts just seem to want to suck that wet cement back out.

You should know that the process isn’t as simple as just filling the post with dry concrete mix. You also need to prepare the post for filling.

The vinyl fence post is a common sight in American suburbs. It’s not as sturdy as a wooden one, but it does offer some advantages over wood.

For example, it doesn’t require any maintenance and you can paint or stain them whatever color you want without worrying about whether they match your house or not.

When you are trying to fill a vinyl post with concrete, you need to follow a couple of steps or your effort will be wasted.

Let’s find out how to do it!

Our Pick

QUIKRETE 110110 Concrete Mix 

This Concrete Mix is designed to provide strength and durability to your projects. It is made of high-quality materials that are carefully blended to provide consistent performance every time. The quick-setting formula ensures that you can complete your project in a timely manner, without sacrificing quality.

How to Reinforce Vinyl Fence Post Using Concrete?

Here are the steps you need to follow to install a vinyl fence on concrete:

1.     Cut the post down to size

To fill a vinyl fence post with concrete, you will need to cut it shorter first, roughly two feet should do it. This is important because if you tried filling a full-length post with cement, the side of the wet mud mix would end up on top of your foundation and that can’t be good! If there are any jagged edges left over from cutting the post down, get rid of them by smoothing them off.

2.     Fill in around posts at ground level

 When you come to fill in around new posts, you’ll find that using a shovel or spade is not going to work for this project. the material won’t stay put and you’ll just end up all covered in mud.

3.     Use the right mixture of concrete

  You need to start with some dry ingredients that can be mixed into a cement-like mixture, then add water to get the consistency right.

A good starting point would be equal parts sand, pea gravel, and portland cement (or other cement/lime mix). Add enough water so it’s wet but not soupy; if you put your hand in there it should stick but wipe off without too much effort.

4.     Pour the concrete insert

  Mix up your concrete at least an hour before you’re ready to do any post-filling because once you open the cement bag (and assuming it’s not self-starting), you have about 60 minutes until it gets strong.

Once you’ve got that goop, pour the half-full bag into the bucket and carefully remove any lumps or dry pockets with a spoon or small trowel. Now dump in your gravel mixture along with some water to moisten the whole thing up again since the dry ingredients will soak up all the moisture pretty quickly.

5.     Fill each post

  When there’s no more room in the bucket for more mix, get rid of any extra water by slopping it around on top of your post where it can run out through holes in the bottom plate.

Then start shoveling that wet concrete into every void inside your posts working from top to bottom without worrying about getting any on the outside.

Once you’ve filled all four posts, go ahead and tamp them down as much as possible without making it impossible to set the u-shaped “toe-plates” in place around the bottom of each post.

Do this by grabbing a corner of each footer and wiggling it back and forth until it starts to settle against your filly tamped concrete insert. Then do that for all four corners before going to the next step.

6.     Let dry

  While waiting for your new fence posts to dry, you can check up on things from time to time by giving them a rap with your knuckles.

They should feel pretty sturdy but not completely hard yet. Give them at least 24 hours to dry before digging holes for your new fence.

7.     Pound in the u-shape plate

  Once the first day’s worth of drying time is up, you can set those toe-plates by pounding on them with a rubber mallet until they’re snug against the ground and won’t move around when you walk on them.

8.     Fill more concrete

  You can use the same mixture as before to fill in around those new posts, adding some water from time to time as necessary and making sure you don’t let it dry out too much.

Once each post is supported on all sides by concrete you can tamp it down a bit but leave some room for more concrete around it.

9.     Bring the fence

  This is the only step that requires a second set of hands, but don’t worry it’s not too hard to manage. Set up your temporary fencing to cover the construction area and then use scrap lumber or even twisty-ties to hold it in place until you’re ready to put in the new fenceposts.

10.     Put it all together

  Finally! It’s time to set the finished posts into their holes and attach them back to your temporary fencing with some sturdy wire or baling twine that’ll hold until you install your permanent post caps.

There’s a pretty good chance you’ll need to adjust the depth of your post holes and maybe even cut out some excess concrete, but once you’re happy with them, tighten your wire/twine against the u-shaped plates and stand back to admire your new fence posts.

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Can you Install a Vinyl Fence Post Without Concrete?

You can install vinyl fence posts without concrete, but it is not recommended. Vinyl fencing is manufactured in standard heights and the majority of them have a requirement for concrete installation.

You can certainly use pressure-treated wood or cedar beams to support your fence. If you are looking for durability, easy maintenance, and low-maintenance costs then installing vinyl fencing is the best choice as it stands up to the toughest weather conditions and does not fade, crack or warp.

Some people want to avoid installing fence posts in concrete for aesthetic reasons. Concrete fencings require a lot of digging and this will render your lawn or garden area temporarily unusable.

With pressure-treated wood and cedar beams, you can install your fence quicker with less disruption to the landscape. A benefit of vinyl fencing is that you do not need to dig holes or mix cement.

Vinyl fence posts are designed for ease of installation and feature a snap base design which eliminates the need for digging, mixing cement, and embedding in your lawn.

Vinyl fence posts can be installed without concrete but the snap base will provide little support. Vinyl fencing is durable up to 80,000 cycles on some models, this is equivalent to 20 years of use.

Find the right fence contractor for your project

If you want to install a vinyl fence without concrete, here are some ways to do so.

  1. Dig a trench – Dig a trench that is deep enough so your post will be about three inches below the ground’s surface. This way, you can place gravel at the bottom of the trench and put sand on top before adding dirt back in. The pit should be as wide as your fence post, which will allow the post to sit flush with the ground.
  2. Install metal stakes – You can install metal stakes that are long enough to go into the ground about three feet. Pound these stakes in at an angle. When you’re ready to install your fence, attach it to the metal stakes.
  3. Attach wire – If you don’t want to use any posts or stakes, you can use wire instead. Attach the bottom of your fence to a metal stake, and attach the top to an existing pole. This will keep your fence together and prevent it from falling over or breaking.


What type of Cement for a Vinyl Fence Post?

Typically, a high-quality all-weather vinyl fence post can handle being filled with concrete that doesn’t have any additives. The problem with filling the vinyl fence posts is that it requires pouring hundreds of pounds of concrete into tightly packed small holes.

In general, avoid using cement mixes designed for below-ground installations. They need to be able to handle being outdoors, including the hot sun.

What are the Alternatives for Concrete?

Our Pick

Fast 2K Fence Post Mix and Concrete Alternative

Fast 2K uses expanding composite technology that’s stronger than traditional concrete and can be used with wood, vinyl, and metal posts. The product is hydrophobic, meaning it repels water, which helps prevent rot, rust, and other water-related damage.

However, if you’re looking for alternatives to concrete, there are several options to consider:

  1. Quick-Setting Cement: Quick-setting cement is a fast-drying option that sets in as little as 15 minutes. This makes it an ideal choice for fence installation, as you can quickly move on to the next post.
  2. Plastic Fence Post Mix: This is a pre-mixed product that comes in a bucket and can be poured into the post hole. It sets in just a few minutes and is a great alternative to concrete if you’re working in a location where concrete mixing is not feasible.
  3. Foam Fillers: Foam fillers are lightweight and expand to fill the post hole. They are a good choice if you need to fill a large area quickly.
  4. Gravel: Gravel is an affordable and easy alternative to concrete. Simply fill the post hole with a layer of gravel, and then set the post on top. The weight of the post will keep it in place.
  5. Engineered Fill: Engineered fill is a combination of sand, gravel, and other materials that have been specifically designed to provide stability to fence posts. This type of fill is ideal if you’re installing a fence in an area with poor soil or if you’re concerned about the stability of your posts.


Filling vinyl fence posts with concrete is a great way to save money. It’s also easy if you have the right materials on hand and know how to follow instructions. Make sure you do your complete research first.

It’s easy to get the mixture wrong and end up with a warped post that doesn’t stand straight up. If you get the ratio of sand to masonry cement right, filling fence posts with concrete can be fun and rewarding.

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