Retaining walls can add dimension to your yard, allow for more use of space, and protect areas. There are several ways to use a retaining wall but building one involves some effort. You should list your specific reasons for needing a retaining wall before starting the project.
Why should I build a retaining wall? Retaining walls are used to change landscapes, especially if there is a slope. They are used to create flat spaces out of sloping hills and stop erosion. This could mean creating garden terrace landscaping, protecting lawns, pools, patios, and driveways from soil and water, and providing additional support for basements.
Read further about how retaining walls are used.
Substance and Structure of Retaining Walls
Retaining walls have one purpose and that is to hold back the soil.
The height of a retaining wall is typically under six feet. Most homeowners create walls that are four feet tall or less in DIY projects. Home advisers general state you should hire a professional to build a taller retaining wall.
Retaining walls can be made out of any number of strong materials including cement blocks, stone, bricks, and wood. The basic construction is the same no matter which of these materials you use but wood requires a few extra steps in the backfill, including waterproofing it with Liquid Rubber.
Waterproofing other surfaces are done with a membrane instead.
Ways to Use Retaining Walls
There are several ways to use a retaining wall to make the most of your slope. Here are a few. Creating Garden Terraces
You can take a yard that is completely on a hill and add several retaining walls to create terrace gardens. By creating layers of flatlands, you can use the land to plant flowers or vegetables and get great use out of the land.
Creating a Wall for Your Basement Walk Out
Many retaining walls are used to create a basement walk-out area. Since basements are built at least in part underground, you may need a wall or two to put in a basement door and outdoor patio.
Creating a Lawn or Pool Area
Those that have a sloped backyard may want a retaining wall to create a flat area near the house to have a lawn or pool.
Preventing Water Flooding House or Driveway
Sometimes, retaining walls are installed around areas of the home to prevent water from running down the slope and flooding the home. This can prevent enormous amounts of water damage in your home.
Retaining walls can change the shape of the yard while adding a lot of decor and dimension. They can be built curved or straight. The different elements can add visual interest. They can be a great landscaping asset that adds value to your yard.
Do’s and Don’ts of Buiding a Retaining Wall?
Some things work well while constructing a retaining wall. Likewise, there are things that home advisors say you should avoid. Here is a list.
Backfill is what you put behind the wall between it and the dirt. Typically, the backfill is either gravel or sand. You should never use dirt as a backfill because it doesn’t drain well enough, gets heavy, and adds pressure to the wall.
You should backfill a few inches with each layer of blocks.
Stack Blocks with a Backward Slope
The wall should slightly lean into the soil so it’s less likely for the soil to push it outward. A retaining wall should be designed to slope 1 inch for every 1 foot of height. Retaining wall blocks are the easiest to work with to make sure this happens.
Choose a Material Easy to Handle
Picking a material that is easy to work with is important to building a good retaining wall. Manufactured blocks are best for DIY work but you can use bricks and cement blocks pretty easily. Stone and woods make for more complicated materials.
Create a Good Foundation
The foundation is the most important aspect of your retaining wall. It needs good drainage and a foundation trend with at least three inches of crushed gravel for smaller walls. Your trench depth depends on wall height.
The general rule is to dig a trench that is one-eighth the height of the wall plus three inches.
Check with Authorities
Some cities and counties require those seeking to build a retaining wall to get a permit first. A retaining wall could affect water flow for neighbors, so Homeowners Associations and city permitting offices may require you to submit plans for any retaining walls and have a property inspection.
You will also need to call before you dig to notify local utility companies of your plans. They will mark where lines and pipes are so you won’t accidentally cut through them.
Don’t Lay Blocks on an Uneven Surface
This is crucial for the first row laid in the trench. It must be level for any of the other rows to be level. You can use a carpenter’s level to make sure the gravel layer is level before you set the first row. Keep checking the level with every row you add.
Don’t Forget Drainage
Drainage is an important part of the foundation. That is especially true if there is a lot of clay in the soil. Saturated soil creates pressure on the wall’s backside. Drainage should be included in the design phase of the retaining wall.
Besides putting in pipes along the base of the wall, you also need to make sure to drill weep holes. Weep holes are small holes spaced evenly along the wall’s base to allow for excess water to flow through. This relieves pressure on the backside of the wall.
Don’t Stop With One Retaining Wall
You can keep your DIY project by opting for more tiered walls to manage a tall slope rather than one large wall. Tiered walls have less soil weight to support so they won’t likely fail. They add visual texture too.
You will need to measure to build tiered retaining walls correctly. The higher wall should be built twice the distance away as the lower wall’s height. For instance, if the lower wall is 4-feet tall, the next wall up the slope should be constructed 8 feet up from the lower wall.
Do retaining walls help with drainage?
Retaining walls, which are properly built, help resolve many drainage issues. They control water flow and prevent erosion as well as make outdoor spaces more appealing.
Can you build a retaining wall on concrete?
No, a retaining wall requires that a trench be built for a foundation. The trench must have gravel and drainage in it to function properly. Concrete doesn’t allow for that.
Are concrete blocks a good material for a retaining wall?
Yes, concrete blocks are an excellent material for a retaining wall. They are easy to install, affordable, and incredibly durable.
Does a 2-foot retaining wall need drainage?
Every retaining wall needs drainage regardless of its height. This is key if you have poorly draining soils like clay. Water must have a way to escape or it will put pressure on the wall.
How thick should a retaining wall be?
Everything is depending on the wall height. The base width should be 1/2 to 1/3 of the height while the thickness should be 1/8 of the height but at least 12 inches. The stem thickness should be 6 inches plus 1/4 inch for each foot of the wall’s height.