Concrete Retaining Wall – How to Build Functional Retaining Walls

Retaining wall construction into your front yard will enhance all the functions of your outdoor living room and increase the appeal of your landscape appearance, sliding-resistant ability, and reduce soil erosion of the sidewalk. Compared with other retaining wall materials, concrete provides much more benefits with a high level of technicality and structural requirement. Concrete walls in particular as well as all retaining walls provide protection against the steep slopes, especially with houses on the high hillside in Seattle WA.

steep slopes in Seattle WA2

When planning to have a concrete retaining wall installed, you should find out what to do first, and whether you should hire skilled workers or a geotechnical engineer to assess the area of your garden. In the steps of construction concrete retaining wall project, it will require professional engineering to keep its shape. In case that your wall in the Seattle area is more than four feet tall, you’ll need to consider finding contractors as well as a structural engineer for grading.

Or contact us for more details!


Lateral Earth Pressure

lateral pressures2hydrostatic pressure

Besides the lateral earth pressures which even overturn the wall, the groundwater behind each wall will cause hydrostatic pressure on the wall if the drainage system could not dissipate that groundwater. That’s why you must install a drain pipe into the retaining wall system.

Size of Footings

The footing depth should be kept at the minimum level of at least two feet and below the seasonal frost line. In some cases, the wall construction will include a footing key to increase the sliding resistance which extends to the bottom of the first course.



The concrete block retaining wall could be installed with any of the following joints, depending on your choice.

Construction Joints

Between two successive poured walls, there are both horizontal and vertical joints used to increase the sliding resistance ability of each joint. If you don’t use keys formed in the base, you should clean and roughen the surface of the first pour and the next one before each next poured concrete.

Contraction Joints

Contraction joints include vertical joints or grooves 0.25 inches wide and not exceeding 30 feet. These joints allow concrete blocks to shrink without any harm.

Expansion Joints

The vertical expansion joints are combined with a concrete retaining wall to calculate whether the temperature changes will make any expansions. These joints should be placed at intervals of at least 90 feet.


You have to check the local codes for requirements and check whether there are any underground utility lines before going to any steps of building the concrete retaining walls. In Seattle WA, retaining walls whose height of over 4 feet will need to have a building permit. In some cases, you want to build the wall at a property line that during the construction process, for example, there’ll be several potential damages to the property and the local government will require you a new construction permit.


The most common cause of concrete block retaining wall collapse is water. The concrete wall seen below failed because of insufficient drainage behind the wall. This wall failure was caused by a combination of the earth sloping toward the wall, no run-off stone behind the wall, and no apparent weep holes or drainage outlets.

weep holes

You need to have the weep holes to allow free drainage throughout the concrete retaining walls. The weep holes need to link with a kind of filter material and the adequate space will permit uniform drainage between the walls.

Keep checking the water runoff and drainage in mind during this construction process and ensure that the water systems from your house will not be puddled and reduce the endurance of stairs. Call 811 – DigSafe to ask about the local utility before you plan to dig anything up. Then determine whether there are any underground lines and mark the exact locations to avoid it during the process.

drainage line



To build a retaining wall DIY, make sure you have these right tools. The process will be easier for you and save your time with them:

  • Round point shovel: This is useful for moving plants, excavating, and establishing a foundation.
  • Square blade shovel: It’s ideal for laying down materials like gravel or sand and grading the region.
  • Tamper: Helpful to tamp down the area.
  • Four feet level: Check to see if the work area and the rows of retaining walls are levels.
  • Drilling Hammers: To drive stakes into the ground, a mallet and a 5-pound maul may be useful.
  • Adhesive and caulking gun: If you wish to attach finishing caps or add steps, these supplementary materials will come in handy.
  • Block chisel
  • Tape measure
  • Circular saw
  • Transit level

In addition, you should prepare safety glasses and a dust mask to protect yourself from physical harm.


You should plan a list of which material you need to buy ahead of time you go shopping. This will help you save a significant amount of money and time. This list will include:

  • Concrete blocks: there is a catalog of each manufacturer that you can opt for your different options of style, color, size, and pattern. Take a firsthand look and compare the prices.
  • Mortar
  • Concrete stone
  • Concrete adhesive
  • Concrete pavers
  • Masonry
  • Gabion Walls
  • Drainpipe

When you prepare all the tools and materials along with you, the next part will show you how to build a retaining wall DIY step by step.

Pouring Concrete Walls Step By Step

Once you first prepare all you need along with you for concrete retaining wall construction, follow these steps to create a wonderful outside living room in your location.

  1. You first design the block walls, including the shape, location, and size you’ve planned to install.
  2. Remove all unnecessary things around the building surface area: topsoil, plants, fragmented rock, gravel, etc.
  3. Excavate and level the base
  4. Digging the footings and building forms.
  5. Insert weep holes
  6. To reinforce the base, add rebar with each-16-inch on the center.
  7. Pouring concrete, footings, and wall
  8. Create joints with 4 – 6 feet (with any types of joints we’ve listed above)
  9. Remove forms and install a drainage system then fill with mortar to finish the surface walls with cap blocks (if you want).
  10. Install patios or other elements you want for your project in Seattle WA.

Feel free to contact us for a free estimate

Call us now – (206) 265-2940

block retaining walls

Note: if the poured concrete wall is applied, you need to have architectural contractors come up with the landscaping design for you to provide enough footings and steel for the project. If you let any problems happen to the poured concrete, that will be a disaster you never ever want! Pay attention to waterproofing and keep moisture at a good level so that it doesn’t strip the wall face, or worse discolor the wall. Although poured concrete might cause some negative effects if not in good maintenance, it still provides a natural look and achieves the organic for your landscape. Block retaining walls are positively worthy challenges!


Building a concrete retaining wall for our home can be simple work, however, it is not an easy one that you can finish within a few hours with little experience. In case you want to design step-by-step retaining wall construction in the Seattle area but you’re not sure about what to begin, the best thing you should do is to find skilled workers in this field to help you. There are many contractors which have experience and the right tools for each work of this constructed project.

Green Arbor Landscaping is the top-ranking company serving customers in the landscaping field in general, and the retaining wall installation project in particular. With 35-year of quality service in landscapingGreen Abor Landscaping is the superior choice for all of your outdoor living needs. Our team members can inform you that we provide a variety of services which vary depending on your different choices. You can search for other clients’ comments about the Green Arbor service site which will absolutely satisfy your expectations with their experiences and enthusiasm.

For more information about Green Arbor Landscaping, here is what you might need to contact us:

Leave a Reply

Your email address will not be published. Required fields are marked *