I like to think I’m a good DIY-er. I’ve always been good with my hands, and have worked hard to be the kind of man who knows how to fix things around the house. It’s not about being macho or trying to prove anything; it’s just important for me to be able to take care of myself. That said, I made a colossal mistake by tackling a cinder block retaining wall in my backyard. Not only was it more difficult than anything else I’d ever done before, but it also took me three times longer than anticipated, and left my back sore for weeks afterward. I learned the hard way that installing cinder blocks is no joke—and neither is building a retaining wall. But taking on that project did teach me how to successfully install them (and finish the wall) so hopefully you won’t make the same mistakes as me!
Gather The Materials You’ll Need
You’ll need the following materials:
- 4 cubic yards of soil
- 2 cubic yards of gravel
- 1 cubic yard of landscaping fabric
- 1 cubic yard of sand.
You’ll also need:
- Cinder blocks, which can be purchased at any home improvement store or online. You’ll want to purchase enough blocks to go around your retaining wall and fill in any gaps between them as well. The size of these blocks is dependent on the height and width you want for your finished project; however, most cinder block walls are built using 12″ wide x 8″ tall blocks with a 3/8″-thick face (or thicker). If this is what you’re going for, then make sure that’s what you purchase! Blocks can be found in various colors as well; I recommend using grey or red ones because they look nice against any color landscape or ground coverings like grasses and shrubs.
Make Sure Your Ground Is Flat
If you want your retaining wall to be straight and level, the ground has to be flat. This may sound obvious, but it’s easy to forget when you’re digging a trench or putting in stakes for posts. Use a spirit level at each end of the wall, and also check that it’s level in all directions by comparing it with another vertical line (like the side of your house). If there are bumps anywhere, use a shovel or garden hoe to smooth them out and make sure they’re not going downhill from left to right.
Lay Down A Base Row Behind Your Marked Line
If you’re using a spirit level to check the base row, place it on the ground and adjust it so that it sits comfortably in front of your first cinder block. Make sure that you have enough cinder blocks in your pile to reach the height that you need for this first row. If not, go back and get more until they’re all there.
Then use a shovel or rake to level out your base row. I personally prefer using a piece of wood as this makes it easier to line up my next block against where I’ve just leveled off.
Fill Each Block With Drainage Gravel
Once you’ve finished setting the blocks, fill each one with drainage gravel. The gravel should be about the size of a quarter and will help water drain through the blocks, preventing erosion and washing out of soil. A 10-pound bag should be enough for your entire wall.
Use Landscaping Fabric To Keep Dirt From Seeping Into The Drainage Gravel
Now that the wall is all in place, you’re going to need to use landscaping fabric to keep the dirt from seeping into the drainage gravel. This will keep any excess water from getting in there and causing your wall to become unstable. To do this, simply lay down a layer of landscape fabric across both sides of your wall and press it firmly into place so that no dirt can get underneath. Finally, use a rubber mallet or hammer (or even a spare block!) to tap each block into place: start at one end and tap along until you reach the other side of your retaining wall.
Place The Next Level Of Blocks On Top Of The Previous Row
- Place the next level of blocks on top of the previous row. Make sure that all of these blocks are level and square (use a level to check), and use a rubber mallet to tap them into place.
- Continue adding rows until you have reached your desired height.
Use A Rubber Mallet To Tap Each Block Into Place
Once you’ve laid out the blocks and drilled holes in them, it’s time to tap each one into place. This requires a rubber mallet, as well as some protection for your block.
To protect the block, use a piece of wood (the same size as the bottom edge) and lay it diagonally across each corner of your cinder block wall. Slide this wooden block under each layer of cinder blocks while they’re still sitting on top of one another on their pallet. This will keep them from getting damaged during transport.
Next, take a masonry bit that fits snugly into your drill and use it to drill holes into each end corner recesses of your cinder block wall so that you can easily fit screws through these holes later on during installation for added support and stability (see [this example](https://www.youtube/watch?v=0jK5JGWul4o)).
Continue Laying Rows Of Blocks Until You Reach The Top Of The Wall.
Continue to lay rows of blocks until you reach the top of your wall. You can use a level to ensure that it is straight, but if you don’t have one handy, look for any obvious issues as you’re building—if there are any gaps or places where it looks like the blocks aren’t flat against each other, fix them before continuing.
You’ll want to make sure your last row has at least 1″ (25mm) overhang on all sides so that rain doesn’t get into gaps between blocks and destroy those joints.
Create A Backfill Area In Front Of Your Retaining Wall Using Dirt And Bagged Gravel
- Once your excavation is complete, you’ll need to create an area in front of the retaining wall where you can fill in the dirt that was removed from the hole. This area is called backfill and should be made of soil that is similar to what’s beneath it so as not to cause any problems with drainage later on.
- If you have dirt available, use it! Don’t worry about getting too much—you can always add more later if needed. If not, buy bags of dirt at your local home improvement store or farm supply store (or borrow some from a friend). Use as much as necessary to fill out the entire space created by removing all those rocks!
- If using bags isn’t an option for whatever reason (maybe there aren’t any stores nearby?), use bagged gravel instead instead! Gravel will help keep everything level while also offering additional support for both plants and people walking across your lawn/patio/etcetera over time
Pour Gravel Over The Dirt In Your Backfill Area, Filling It In Completely.
Now that you’ve removed the top layer of dirt from your backfill area, it’s time to finish filling it in with gravel. Pour enough of this material over the dirt so that there are no gaps between each cinder block and also no drainage spaces between them. The gravel will act as a barrier against erosion, weeds and water seepage into your drainage system.
If you’re installing a retaining wall close to an existing building or structure, then you may want to include some wire mesh so that the dirt doesn’t erode away under the pressure exerted by gravity or heavy rainwater runoff.
Lay Landscaping Fabric Over The Gravel, Pinning It Place.
Lay landscaping fabric over the gravel. It’s important that you use a UV resistant landscaping fabric, so it won’t disintegrate in the sun or break down when exposed to moisture. For this reason, you may want to purchase special landscape fabric from your local hardware store or garden center.
If you don’t happen to have any on hand, don’t worry! You can easily find some at your local hardware store, just make sure it’s not made of any plastic or rubberized materials (they’ll melt in high temperatures).
Plant Flowers And Plants In The Backfill Area To Finish Off Your Retaining Wall.
Plant flowers and plants in the backfill area to finish off your retaining wall. Flowers and plants will help to soften the look of the wall. You can also add shrubs and trees to the backfill area. It’s important to use a variety of plants in your design so that they fill out your landscape as much as possible.
It’s not too difficult to build a retaining wall by yourself.
If you’re considering building a retaining wall by yourself, there are a few things to keep in mind. First, you should have the right tools and materials, including a spirit level, levels, shovels and wheelbarrows. Second, you’ll need some skills and knowledge—specifically in masonry techniques—in order to build the wall securely. Thirdly (and most importantly), your attitude will help determine how successful your project is. You can only get so far if your attitude isn’t positive or if you don’t care about learning new things along the way!
Conclusion
After reviewing the steps to install a cinder block retaining wall, you should be ready to go. You can find much more detailed information in your local building code. If you need to hire someone to do this work for you, the Retaining Wall Estimator tool can help you gauge how much materials you need and what it will cost. If at any point during the installation process you are unsure about something, talk with your building inspector or contractor for clarification on what needs done correctly before moving forward on any additional steps.
