How to Build A Concrete Retaining Wall

A concrete block retaining wall is probably one of the most friendly do-it-yourself solutions to the home landscaper. You can safely and effectively grade a sloping yard or add a decorative feature to your landscape design by simply adding a basic concrete retaining wall over your next long weekend. The job will be a lot of work but it will add value to your home. This guide will walk you through the basics of building your own concrete retaining walls out of cement bricks.

Instructions

1. Contact your local utility company to inspect and mark underground wiring and piping. Because the first steps to building your concrete retaining wall require digging into the ground you will not want to accidentally damage these potential underground hazards.

2. Contact your local building code official before starting your dig. Your local requirements may differ slightly from what you believe them to be and you may need a permit before building a raised retaining wall.

3. Arrange for your local landscaping supplier to deliver the concrete blocks and materials to your job site. Depending on your brand of blocks each one can weigh between 50 and 100 pounds each.

4. Begin digging the trench that the base of your concrete retaining wall will rest in. The trench will have to be deep enough to accommodate half a foot of compacted base materials, an inch of leveling sand, and half the height of your first layer of concrete blocks.

5. Place roughly six inches of base material into your trench all the way across and compact it down with a tamper. Be very careful to finish the base off absolutely level. The integrity and strength of finished concrete retaining walls rely heavily on a firm and level base. Use a long level to ensure a perfectly flat and level surface before moving on.

6. Lay a one inch layer of leveling sand on top of the compacted base material. Again make very sure the sand is uniformly spread and level all the way across.

7. Lay your first layer of concrete bricks on your prepared base being very careful not to leave gaps between bricks. The finished retaining wall won't be as structurally sound if gaps exist. You may wish to use brick tongs for safety when laying the bricks.

8. For each successive layer of concrete brick overlap the vertical seams of the previous layer by a few inches and lay the entire layer of brick back by half an inch. This will retain the strength and durability to the retaining wall as well as make it more aesthetically pleasing. Your brand of concrete blocks may come with a system to align and fortify the vertical levels. Follow your manufactures instruction if these features are part of your system.

9. As you build the concrete retaining wall layer by layer, backfill the wall with gravel up to six inches from the final top of your finished wall. The gravel will fill the gap between the concrete retaining wall and the earth that is being held up.

10. Once you get to the desired height for your concrete retaining wall secure a concrete block cap to the top layer of blocks. The cap is set forward a few inches from the top layer and secured to the top with concrete adhesive which can be found at all home stores.

11. Backfill the remaining six inches of space behind the concrete retaining wall with top soil.

Tips & Warnings

• If you need to build concrete retaining walls higher than four feet you will have to take extra precautions and steps which are not covered in this guide. It is highly likely that your branded concrete block manufacturer has guidelines for tall retaining wall projects for you to follow.