There are many things to consider regarding your do-it-yourself (DIY) fence installation and the use of concrete. According to an Angi survey in 2020, 24.7% of people in the United States have attempted a landscaping DIY project, which includes the self-installation of fences. Many of these fences use concrete to keep them in the ground.
At Northland Fence, we have been family-owned and family-focused since 2004. Our employees are in-house, paid year-round, and even work during the off-season, ensuring you can have your dream fence installed no matter the season. Using a fence company like Northland Fence can help make your fence installation more manageable; however, many people may wish to take on the task themselves. In turn, they may ask, “How much concrete per fence post?” when they are in the planning stages of their project.
The short answer is yes. Here in Minnesota, we experience harsh winters, which create problems for fences. One such concern is fence heaving, which occurs when the ground freezes. When the ground freezes, it displaces everything in its way, including fence posts. If your fence post is not at the proper depth nor has enough concrete to hold it in place, it can experience this displacement.
How big your fence post is impacts how deep you will need to dig for each fence post and how much concrete you will need per post. Concrete fence posts require people to dig each hole themselves. You will also need to plan your installation around the weather, as different types of concrete require different conditions for drying and curing. It is also essential to call utility companies before you start digging to ensure you won’t hit utility lines or pipes with your post holes.
For a 3x3 post, each hole you dig must be at least 9 inches in diameter. How much concrete you use per post will depend on how deep your hole is, which is determined by at least ⅓ of the height that your post is above ground. For example, a 6-foot-tall fence is at least 2 feet below ground. In this example, if you had 50lb bags, you would need 2 bags of concrete for every fence post.
If you were to use a more extensive post, such as a 6x6, the diameter of the hole would be 18 inches. Assuming you are still building a 6-foot fence, you need 2 feet underground. These numbers together mean you would need 7, 50-lb bags of concrete for every fence post. The more extensive the fence posts, the more bags you need, which can become expensive.
When you have decided to install a fence by digging holes and using concrete, there are several things you need to consider before you dig any holes. In the middle of your project, you don’t want to run the risk of running out of concrete and needing to make a last-minute trip to the store, which could lead to your project taking longer.
As detailed above, the depth of your hole for your fence post determines how much concrete you need. A 3-foot fence with a 3-inch diameter requires a hole different from an 8-foot fence with a 6-inch diameter. For the 3-foot fence, you would need a hole depth of 12-18 inches, while the 8-foot fence would need a hole of 32-48 inches deep. From there, you can figure out how much concrete you will need to buy per fence post. Following our example, the 3-foot fence will need approximately 1 bag of concrete per fence post, while the 8-foot fence will need 10 bags. Then multiply that number by the number of fence posts needed for your specific project, and you will have the total number of bags of concrete you need based on fence post depth. Below is a chart with common fence post-depth sizes:
Fence post depth is only one of many considerations when deciding to take on your fencing project. What your soil is like can also affect how much concrete you need to keep your fence upright. If you have dense soil, your fence will be more sturdy, which could require less concrete. However, if you have fine, sand-like soil, your fence posts will be more likely to start heaving. To prevent this from happening, you must dig your post holes deeper, which will require more concrete.
In Minnesota, it is essential to consider the frost line when installing your fence and determining the amount of concrete you need for your project. The frost line is how deep the soil will freeze. When the soil freezes, it shifts and expands, which impacts your fence posts. Your fence post should be at least 6 inches underneath this frost line. Having your fence post below the frost line will prevent it from moving when frost comes and goes. The frost line in Anoka County, MN, is 3 feet and 6 inches. If we take our 3-foot fence from earlier, we need a hole at least 4 feet deep instead of the typical 12-18 inches. Because we now have a deeper hole, we need more concrete bags to fill it. This project is getting expensive.
Many different concrete mixes exist, and determining which is best depends on your local supply, demand, and budget. Concrete with a shorter curing time will allow your fence-building project to go faster, but it may compromise the structural integrity. Many choose ready-mix concrete, but any concrete will do. You must be willing to mix, pour, and wait for it to dry.
The most significant downside to installing fence posts with concrete is that they need to be more manageable and accessible. It can also get expensive when you factor in how many bags of concrete you need for every fence post you want to install. You might wonder if there is an easier, cost-effective, and cleaner method to get your dream fence without worrying about what Minnesota’s weather will do to all your hard work.
The good news is that there is a better alternative. This alternative is driven fence posts, which you or a contractor drive into the ground instead of concrete. These fence posts go into the ground at a minimum of 4 feet. This 4 feet is where they need to be with Minnesota's frost line. Also, there is no need to worry about mess or concrete mixing, pouring, and drying.
Due to their depth and installation process, Driven fence posts have little to no risk of experiencing heaving. Concrete bases have a chance to heave, no matter how much concrete you use. In the winter, you won’t have to worry about your fence as it will remain solid and secure all winter. Installation is also faster for driven fence posts, as you don’t have to wait for concrete to be mixed, poured, and dried.
At Northland Fence, we install driven fence posts in vinyl fences, ornamental fence, and chain-link fence styles. The multiple styles available ensure you get the dream fence you have been looking for while avoiding the mess you would receive with a concrete-based fence. At the same time, you can rest assured that your new fence will last for several years and be able to withstand whatever Minnesota’s winters throw at it.
Northland Fence has been family-owned and family-focused since 2004 in Ramsey, MN. We always have supplies in stock and never have hidden fees. For more information, feel free to call us at 763-316-4881.
Whether you’re looking for a beautiful, maintenance-free vinyl privacy fence, a sturdy chain link fence, or a ornamental fence, we’re ready to show you why we’re Minnesota’s highest and best rated fence company.
Use this form to request a free estimate or call us at 763-325-8211.
6390 McKinley St NW, Suite 150
Ramsey, MN 55303
763-496-4813
Monday: 9 AM–5 PM
Tuesday: 9 AM–5 PM
Wednesday: 9 AM–5 PM
Thursday: 9 AM–5 PM
Friday: 9 AM–5 PM
Saturday: Closed
Sunday: Closed