retaining wall blocks why bury first course

by Dr. Hailie Bogisich Published 3 years ago Updated 2 years ago 9 min read

To keep the bottom row of blocks from pushing outward, bury the lowest section of a retaining wall. The general rule of thumb is to bury about one-eighth of the height of the wall. For example, if your wall will be three feet (36 inches) tall, the first course of blocks should start five inches below soil level.

Full Answer

How deep should retaining wall blocks be buried?

Apr 23, 2021 · Step 1: Dig for the First Row of Block. With the layout marked, you can begin digging the trench. To bury the first course or first row about halfway, dig the trench about 4 to 6 inches deep and 12 inches wide or twice the width of the block. Caution.

Do you have to bury retaining wall footings?

Sep 03, 2020 · The industry recommends that your first course be buried a minimum of 1ft (2.5cm) for every foot (.3m) in wall height, or 6ft (15cm) (whichever is greater) if the ground in front of your wall is flat. For unique applications where a slope is running away from the face of the wall (pictured below), the industry has a different recommendation of ...

How to build an interlocking retaining wall?

Fill the hollow cores and a minimum of 12 in. (300 mm) behind the wall with wall rock. Install the wall rock to be level or below the receiving notch of the anchoring unit. Use approved soils to backfill behind the wall rock and in front of the base course. Use a plate compactor to consolidate the area behind the blocks.

How do you lay the first course of a retaining wall?

Dec 28, 2020 · The general rule of thumb is to bury about one-eighth of the height of the wall. For example, if your wall will be three feet (36 inches) tall, the first course of …

How deep should the first course of a retaining wall be?

about 4 to 6 inches

Dig a Trench and Level the Ground

Begin digging into the ground with a shovel. The trench should be deep enough to bury at least half the height of your first course of blocks as they sit on a 2- to 3-inch base of gravel. Depending on the size of your blocks, this depth will be about 4 to 6 inches.

How do you set a first course on a retaining wall?

Part of a video titled How to Install a Retaining Wall Base Course - YouTube

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Place the blocks tight together checking each block for level and alignment from side to side andMorePlace the blocks tight together checking each block for level and alignment from side to side and front to back. Make minor adjustments by tapping the blocks with a dead blow hammer.

How do you prepare the ground for a retaining wall block?

Prep and Lay the Retaining Wall Block

Step 1: Dig for the First Row of Block. With the layout marked, you can begin digging the trench. ...
Step 2: Adjust for Sloping Ground. If the trench slopes, you'll have to step up or down to keep the blocks level. ...
Step 3: Level the Ground. ...
Step 4: Add Paver Base.

What do you put down before a retaining wall?

Part of a video titled How To Build a Retaining Wall (Step-by-Step) - YouTube

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And get it slightly damp to help it pack down a little bit better and once you've built up sixMoreAnd get it slightly damp to help it pack down a little bit better and once you've built up six inches of gravel base.

How do you put landscape blocks on uneven ground?

Part of a video titled Building Retaining Wall Step-Ups into the Slope - YouTube

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Make sure that the blocks in the base of the second step up are level compact behind the block in aMoreMake sure that the blocks in the base of the second step up are level compact behind the block in a path parallel to the wall working from the back of the block to the back of the backfill.

Do I need to put landscape fabric behind retaining wall?

You should use landscape fabric behind a retaining wall because the fabric supports the bricks, wood, or other materials that make the wall. Wet soil can push against a retaining wall, weakening it. By placing a strip of landscape fabric under the soil, the wall won't have as much pressure on it.

How deep should a footing be for a block wall?

Normally a foundation wall with seven rows of blocks will be 24 inches wide and 12 inches deep and should have a footing 30 inches below grade. Remember to build a leveled footing where the cinder block will be placed.Dec 13, 2021

Does a retaining wall need a footer?

Every retaining wall needs a footing, but what type depends on the design, material, height and weight of the wall. Large masonry retaining walls built out of rigid materials like concrete, cinder blocks, cement or brick need a concrete footing. Solid masonry walls are stiff and unable to flex because they'll crack.

How deep should a concrete footing be for a retaining wall?

Concrete retaining wall footing size

The depth to the bottom of the base slab should be kept at a minimum of two feet. However, it should always be below the seasonal frost line, and that often is much deeper in northern climates.Jun 26, 2020

Do I need drainage behind retaining wall?

Behind the wall, a drain system must be placed to prevent water from pooling and undermining the structural integrity of the wall.Aug 9, 2021

How do you backfill a retaining wall?

How to Properly Backfill a Retaining Wall

Lay your base of compacted native soil (about three inches deep).
Tamp the soil to ensure that it is secure and firm.
Fill the next six to twelve inches with aggregate or gravel.
Tamp the gravel or aggregate to ensure a sturdy base.

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Nov 20, 2020

Do retaining walls need building regulations?

Independent, freestanding retaining walls may not require building regulation approval; however, any structures must be structurally sound and well maintained.Nov 4, 2021

September 3, 2020

One of the great things about segmental retaining walls (SRWs), is the fact that the installer does not need to excavate to frost depth and/or pour a concrete footing below the structures. This helps reduce cost and speed up the installation of the systems. SRWs are flexible in nature, and only require minimal burial below grade.

How Much of the Base Course Should I Bury?

Difficulty: Advanced

Retaining walls keep landscape soil from eroding, but they also make a beautiful landscaping feature. A well-placed retaining wall can create more usable space in your yard, especially when your yard is naturally sloped or hilly. Building a retaining wall is a straightforward project that offers many benefits and landscaping opportunities.

Construction Adhesive

Here are some things to know before you start buying material and building a retaining wall:

What materials are used to build retaining walls?

Retaining walls can be constructed using a variety of materials, from poured concrete and large timbers to natural stones, even bricks. For DIY purposes, opt for manufactured blocks that are designed specifically for building retaining walls; a locking flange along the bottom edge creates a secure attachment between rows.

How deep should a retaining wall be?

The exact depth of the trench depends on the proposed height of the wall, but follow this rule of thumb: Dig a trench to be an eighth of the wall plus three inches. For example, if you want the finished height of your retaining wall to be three feet (36 inches) tall, you’d need to dig the trench eight inches deep to accommodate three inches ...

What is DigSafe 811?

While you’re at it, do also place a call DigSafe (811), a nationwide service that will notify local utility companies that you plan to dig. These can determine whether their buried lines will be in the way and mark their exact locations. Advertisement. Photo: istockphoto.com.

How to Build the Base Course (First Course)

Begin the base course at the lowest wall elevation. More information on retaining walls where the wall steps up a slope.

For AB, AB Aztec & AB Europa Walls

Place all blocks with the raised front lip facing up and forward on the base material near the front of the base trench.

For AB Fieldstone Walls

Using AB Fieldstone's two piece system for straight walls is quick and easy.

Do retaining walls hold back soil?

Does your yard contain slopes, dips, and inclines? Then you likely have a retaining wall somewhere on your property. Used everywhere from highway construction to landscaping, retaining walls hold back earth that would otherwise erode or collapse. Homeowners often rely on retaining walls to keep soil steady in elevated yard features, but they can also use the manmade structures when planting tiered gardens on a sloped area of yard, controlling erosion on an incline, or creating an elevated sitting spot. If you’re thinking about constructing a retaining wall, here’s all you need to know about the supportive structures.

What is retaining wall?

Retaining walls have a wide variety of uses around the yard, all of which involve keeping earth from spilling off a steep slope. They’re indispensable in the creation of sunken patios, walkout basements, and any other hardscape with an abrupt separation of ground elevation. You’ll also find retaining walls in parks and public gardens, where they act as retainers for plants, statues, and decorative landscaping elements.

How much does a retaining wall cost?

A natural stone or brick retaining wall laid by a mason can cost upwards of $20 per square foot, and a poured concrete retaining wall will set you back $13 to $18 per square foot.

What is a step back wall?

This design, known as “step-back construction,” creates a sturdy wall structure that pushes back against the lateral pressure of the soil behind it . Step-back walls can be built by anyone with a strong back and basic construction knowledge, as long as they have blocks designed for retaining wall assembly.

What is gravity wall?

You could also add extra strength with a “gravity wall,” which is so wide that its weight serves as a buttress against the pressure of the soil behind it. This type of wall isn’t common, however, because it requires an extensive amount of stone or concrete for construction.

Does soapstone work on retaining walls?

The downside is that soapstone doesn't work as well on retaining wall wet blocks. You can find these inexpensive pencils at online retailers.

Who owns Blakeborough Hardscapes?

Joe Blakeborough (right) owns and operates Blakeborough Hardscapes in Prior Lake, MN, with the assistance of his younger brother, Jake (left). They run multiple crews that specialize in block and boulder retaining walls, paver projects, outdoor living spaces and other services.