Pro Tips for Constructing a Block Wall

The construction of a cinder block wall.

A quality block wall can add both functionality and aesthetic to your landscape. But while these enclosures offer security, style, and privacy to the yard, building them is not an easy task. With a little hard work and lots of determination, however, putting up a block wall is something you can accomplish. From prepping blocks to striking the joints, here are eight professional tips for constructing a block wall.

1. Prepare a Solid Footing

A good footing is key when constructing a successful block wall. The footings should be around twice the width or more of the block and be placed below the freezing line. You also might need a special permit for constructing block walls, so make sure you double-check the building codes in your locale and make the necessary adjustments.

2. Start With the Corners

You usually want to construct the corners of the block wall first and then work your way inside on the courses. The corners are typically referred to as the “leads” and should be at least three to five blocks high before you start the courses. You can snap a chalk line for each course to keep everything nice and straight.

3. Construct a Dry Run

Before you start buttering blocks with mortar, do a dry run of the layout. This will ensure you have enough blocks to finish the job and have the proper spacing between units. You should have about 3/8 of an inch spacing between each edge. Once the blocks are in place, count how many make up the perimeter and figure out how high you want the wall. A little bit of math will tell you how many blocks you need to finish the job.

4. Mortar Mixture

It can be tricky to determine when the mortar is ready to place. One trick is to flick a full trowel in a downward motion to remove excess material. If the mortar hangs on the trowel at a 90° angle, then it's ready to use. Before you lay down the first layer of mortar, make sure you dampen the footing to provide better adhesion.

5. Buttering Techniques

The construction of a cinder block wall with a trowel and mortar.

It's easier to butter a set of blocks at the same time rather than individually. Simply place them on one end in a row and butter them together, using a downward motion with the trowel will help place the mortar in a uniform pattern. When you reach the inside edge of a block, press down on the trowel to keep the material from slipping off.

6. Cleaning Mortar

You should always allow the motor to set a little before scraping it off the surface. If you try to remove the mortar too soon, you run the risk of smearing it, which makes it harder to clean later. Once all the mortar has dried, use a stiff brush to gently remove dirt and fragments from the seams.

7. Measurements

The construction of a brick wall with a level.

It's always a good idea to check for plumb, square, and level throughout the build. This will help you avoid any major mistakes that can't be fixed without making big adjustments. You should also periodically check the mortar’s firmness by indenting it with your thumb. If you can barely make a dent in the mortar, it's time to strike the joints.

8. Striking the Joints

Striking the joints is easier than it sounds, though you need to make sure the mortar is properly set before doing so. To strike the joints, simply use a jointing tool to smooth and compress each and every joint. This process will also remove excess mortar and make the joints appear cleaner, giving them each a slight concave shape. It's a good idea to begin with the horizontal joints and then finish with the vertical ones.