If you want to add a raised bed or patio to your yard, a retaining wall is the perfect way to hold it up. For this project, we’ll show you how to build a 4-foot tall retaining wall using manufactured stone on top of a gravel and concrete foundation.
1. Choose the wall location
The first step in building a retaining wall is choosing the location for the wall. The three most important considerations when selecting a location are that it be stable and secure, at least 3 feet away from any building or structure, and at least 3 feet away from the house. You should also make sure that your soil is level so that you don’t have to go back and add fill dirt later on.
You’ll want to dig a hole for your post foundation about 2 feet deep and 6 inches wide (or as indicated by local code). Make sure you use a post anchor if one is required by local codes. Pour gravel into this hole until it’s about 1 inch from being full; then pour concrete into it until they’re both filled with concrete all the way up to ground level (this should be done after all of the posts are set).
2. Discuss Your Plans with Your Local Bureau
Before you start your retaining wall project, it’s important that you check with your local bureau to determine whether a permit is required.
- If the retaining wall will be built on a steep slope, you may need a permit.
- If the retaining wall will be built in a wetland area or within 100 feet of an environmentally sensitive wetland area (ESWA), then you will have to obtain approval from the United States Army Corps of Engineers (USACE).
- You may also need approval from USACE if the proposed retaining or barrier structure is located within 100 feet of a floodplain or any regulated waters such as rivers and streams. In addition, if your plans require planting vegetation on any side of your slope, then they must be reviewed by an engineer before they can be approved by USACE.
3. Excavate the Area Where the Wall Will Go
Excavation is a process where you dig up the soil and rock that would be in the way of your retaining wall. Excavation is necessary for creating a foundation for your retaining wall, but you should also consider excavating the area if you want to create a patio under it.
- Start by digging out an area that is 4 inches deep. This will allow room for compacted gravel and concrete at least 6 inches thick, so that it can support the weight of people walking on top of it without sinking into mud or sand. Create levels from 0 feet above sea level to 30 feet below ground level using wooden stakes marked with numbers. Excavate around each stake until all soil has been removed from within its radius of influence. Remove any trees found growing within this radius as well; they may interfere with construction or pose safety hazards later on down the line
4. Dig Trench for Foundation
Next, you will need to dig a trench for the foundation. This should be wide enough and deep enough to accommodate your wall’s foundation as well as any surrounding plants that may be affected by its construction.
The trench should also be straight and level in order to ensure that your final wall will stand straight with no problems.
5. Pour Footing
You’ll need to make sure that the soil is compacted and firm before you start pouring. Begin by placing a few stakes into the ground at each corner of your patio and then stringing a level line between them. You can use chalk or string line spray to mark the ground, but it is important that your measurements are accurate since you won’t be able to move once you start laying concrete.
Because this retaining wall will sit on top of concrete footings, they must be poured before any construction begins on the actual patio itself. Once poured, these footings will support both earth and gravity loads from above as well as hold up any potential weight from behind (such as water).
First things first: Make sure that your base material is stable enough for this project! The worst thing that could happen here would be for everything else go smoothly only for partway through pouring concrete footing foundation broke through due lack stability underneath…that would just throw off entire balance calculations later down line when installing retaining wall posts etc., so double check first time around now! Then measure out where each post will go based upon how far apart you want them spaced out along length side; do same thing widths wise too (make sure both sides equal distance apart just slightly wider than widths dimension) so when we finally put together faces during next step later on everything looks nice straight lines all around without having uneven gaps anywhere along perimeter edge line
6. Level Wall Blocks and Mortar Them in Place
- If you have not already done so, mortar the blocks in place using a trowel.
- Use a level to check that each block is level before applying mortar to it.
- Spread the mortar over the surface of each block with your trowel, working from left to right across each row and then moving down the wall as you go along until you reach ground level or your desired height for this section of wall (which should be at least 1 inch higher than any other part of your retaining wall).
- Smooth out any wrinkles or bubbles using another clean section of your trowel and then let dry overnight before proceeding to step 7 below
7. Backfill Behind the Wall
After you get the wall built, it’s time to backfill the area behind your retaining wall with soil. This is where all that time spent digging and measuring comes in handy! Your goal is to have the ground level at the base of your wall, so make sure you use a level to check for accuracy.
Once you’re confident that everything’s level, pack down any excess dirt by hand (you can also use a tamper). It should look just like it does on either side of your new patio—no gaps or slopes! If there are holes left over from rocks or roots in your new patio bed but they don’t extend into nearby grassy areas, consider filling them in with topsoil before placing turf or mulch over them.
If water accumulates behind this type of retaining wall during heavy rains or snow meltings, it could cause erosion or silt-up near its base; avoid this situation by keeping rain gutters clean and free flowing while also making sure they’re sloped away from walls whenever possible—and don’t forget about drainage ditches beneath walkways leading away from buildings (or patios) too!
How To Build A Small Retaining Wall For Patio
To start, choose the location for your retaining wall. You should consult with a local building or zoning department and discuss your plans, but generally you’ll want to make sure that you’re not putting it too close to any utilities like gas lines or electric wires.
Next, dig the area where the wall will go so that there is an 18-inch trench on both sides of where the wall will be placed (about 3 feet wide). Make sure that this trench has a firm base under it so that when you pour concrete into it later on in this process, it doesn’t crumble away from underneath your foundation blocks. To do this properly requires digging deep enough so as not only make sure that there’s enough room for drainage runoff water but also for cement backfill material (called “mud”) later on in step 5 above).
Now dig another trench behind where you plan to place your retaining wall—this will be used for backfilling after laying down all those blocks since they won’t fit snugly against each other without some space between them first
These are just some of the things you need to know when building a small retaining wall for your patio. You can use it as a guide or you can also hire someone who specializes in this type of work if that’s what you want.