Fences themselves have many intended uses ranging from privacy to safety. We use them to establish boundaries and provide some added security. So, can they also be used as retaining walls?
You should generally avoid using a fence as a retaining wall. Fences are not built to sustain the extra burden of holding back dirt and soil. Using a fence as a retaining wall requires extra planning and preparation to strengthen your fence to withstand the added pressure.
There are four things you will need to know before you use your fence as a retaining wall. Below, I laid out some of the main points for you to go through to help you decide what to do.
Point 1: What Is A Retaining Wall?
First off, let’s establish what a retaining wall actually is.
A retaining wall is basically a strong, rigid wall used for supporting soil laterally. They are designed to retain the soil in a shape it wouldn’t normally make on its own. Some instances where this might be used include: a height difference between parts of a yard (i.e. if you have uneven terrain in your backyard), in a garden, to create level areas for driveways, for decks, and even for a children’s play area.
Retaining walls are most often made of wood or concrete (either poured or in blocks) and typically range in height somewhere between 1 to 3 feet. Any taller than that requires extra planning and most likely a required permit of some sort to allow you to build it. So before you make your fence into a retaining wall be sure to check with your specific city to see if you need any permits.
Don’t forget to check with your neighbors as well, if you have any living next to you, because they might want to discuss the project with you. You want to be considerate as it might bring up some problems for them that you hadn’t considered yet.
Point 2: Kickboards
Sometimes called a “rot board,” kickboards are horizontal boards placed along the bottom of a fence panel and are used to keep fence posts from being on or too near the ground. Their main purpose is to help a fence last longer by keeping the pickets from making contact with the ground, thus helping them to prevent decaying and rotting as quickly.
Now, what do kickboards have to do with retaining walls? The thing is if you are planning on using a fence as a retaining wall make sure you do not use kickboards along the bottom. Kickboards are not meant to be used as retaining walls and will make your fence much less stable if you use them this way.
Point Three: Choosing The Type Of Fence
It’s important to consider the type of fence you plan to use for your retaining wall. Obviously, a chain link or wrought iron fence wouldn’t be very effective! But what about wood or vinyl fences? Wood is the most common material used for retaining walls besides concrete, so it would be the preferred option for a fence and in this circumstance.
If you use wood for your fence/retaining wall, it is strongly recommended that pressure treated boards be used. Since you really shouldn’t use a kickboard, pressure-treated boards work well because they work much better for contact with the ground. When these boards are made, the air is extracted when they are sealed and this space is filled with chemicals. Taking out the air allows the chemicals to be carried deep into the wood and thus improving the quality to be used for a fence.
If pressure-treated boards aren’t used, your fence will begin to rot and decay even faster than it already would with dirt being placed against it. Using this specific type of wood will help to extend its lifespan. You will still probably see the effects of the dirt and moisture on the fence over time, but it will take longer to actually affect the material.
It is required for retaining walls made of wood to have added posts placed every few feet (typically 3 to 4 feet), as a way to support it and provide a stronger wall for it’s intended purpose. If a fence is not properly supported and then has dirt put against it, it won’t be long before the wood (or maybe even vinyl) begins to warp and shift.
Something you can do to strengthen your fence while turning it into a retaining wall is by placing some horizontal planks along your fence for however high you plan to place your dirt; this is not like a kickboard because the fence planks are still on or near the ground, and not placed on top of the horizontal planks.
Point 4: Fences On Top Of Retaining Walls
This is probably something you’ve seen before. It’s known as a fence with an integrated retaining wall and is a great option where you can have a sturdy retaining wall and a fence. They are also a wonderful option because if you put in a small retaining wall, you probably won’t need to worry about as many permits and can still work on installing a fence on top for added height and privacy.
These types of fences are typically seen as a wrought iron or vinyl fence placed on top of a concrete or wood retaining wall. My elementary school had a fence like this. It was a concrete retaining wall topped with a wrought iron fence because our building was on the edge of a slope and something was needed to hold back the soil from spilling onto the sidewalk running along the ground just below.
The fence itself can be installed either in the wall or behind the wall. Difficulty doing either of these will also depend on if the retaining wall was already there or not.
While it really isn’t really the best decision to use a fence as a retaining wall, there are a couple of ways to make it a possibility if it’s a project you’d like to undertake. Just be ready for some necessary extra preparation! Source