How to Build a Brick Garden or Patio Wall

You can use a brick wall in your landscape for a variety of purposes, such as defining the limits of a flower bed, establishing a boundary between discrete areas or simply providing visual interest. Building a brick wall doesn't typically qualify as a DIY project because mistakes can lead to potentially hazardous instabilities, but if you keep the height of the wall to 3 feet or less, there's little danger of a serious accident. Nevertheless, a visit to the local planning department to inquire about any permits you might need is a prerequisite for any brick wall project no matter how high you plan to build it.

On the face of it, all it seems you have to do to build a brick wall is to stack bricks neatly with mortar between them, but the process of bricklaying is a bit more complicated than that. The wall has to be built on a solid, level concrete footing that is deep enough to support the wall and withstand seasonal freeze-thaw cycles. The arrangement of the bricks themselves and the number you use also affect stability. A half-brick wall consisting of a single course of bricks isn't as stable as a one-brick wall, which consists of two courses laid side by side. Half-brick construction is suitable only for walls no more than 18 inches tall.

The dimensions of a standard brick, according to the Belden Brick Company, are 3 5/8 x 8 x 2 1/4 inches. The width is approximately half the length, so a wall constructed with a single course of bricks laid end to end is known as a half-brick wall because the total thickness of the wall is equal to half the length of a brick. Another possible justification for the "half-brick" designation is that each alternate course starts with a half brick to create the alternating joint pattern.

A one-brick wall, on the other hand, is constructed by laying bricks side by side instead of end to end. A variation is to stack bricks alternately, placing two side by side, parallel to the wall direction and followed by one perpendicular to the wall, as demonstrated by Sikana English on YouTube. In this and other arrangements, the bricks running parallel to the wall are called "stretchers" and those running perpendicular are called "headers."

Bricks come in a wide variety of sizes, so you don't have to settle for standard ones. They range in length from 7 5/8 to 15 5/8 inches in length, from 3 5/8 to 7 5/8 inches in width and from 1 5/8 to 7 5/8 inches in thickness. Because a garden wall is typically visible on both sides, you'll want facing bricks as opposed to backing bricks, which the Constructor says are typically used inside a brick structure and aren't as cosmetically pleasing. Generally, you'll want all the bricks to be the same size, although it's fine to mix in some thinner ones as long as they have the same length and width.

Burnt fireclay bricks, which have the familiar red or terra cotta coloring, come in four classes, and although lower-class bricks absorb too much water to be useful in building construction, they're fine for a garden wall, and they are less expensive. In addition, you can choose concrete bricks or sand lime bricks, which are designed for ornamental purposes, such as garden walls. You can even use recycled bricks if you can clean off all the old mortar.

Some bricks have a more-or-less deep impression on one side called a frog, which makes the brick lighter. Some masons say the brick should be laid with the frog facing up so you can fill it with mortar and make the wall stronger, while others claim that it should face down to facilitate leveling the mortar for the next brick. A garden wall doesn't have to be as strong as a building wall, so it's probably fine for the frog to face down.

Construction of a brick wall begins with staking out the course of the wall and marking the ground. You then need to dig a trench for the footer (it's advisable to call 811—a national service that connects you to officials who determine where underground utility lines are buried so that you avoid causing any damage—before you dig). The footer dimensions are based on the height and thickness of the wall and also on the soil quality. It should have straight edges and extend below the frost line to prevent heaving in the winter that could damage the wall.

For a wall 3 feet or less in height, DIY Data advises that 12 inches is usually a sufficient depth in firm ground, while in loose soil, you should dig at least 18 inches. For a half-brick wall, the width of the footer should be three times the width of the wall or approximately 11 inches for standard bricks.

After digging the trench to the appropriate depth and leveling the bottom, drive a metal peg that rises to the height of the finished footing, which is typically one or two brick thicknesses below ground level. Once you've verified it's at the proper height, drive several more pegs along the length of the trench using a 6-foot spirit level to make sure they rise to the exact same height. DIY Home & Garden recommends dropping an inch or two of drain rock into the bottom of the trench followed by standard concrete mix, and when you pour the concrete mix, it should rise to the tops of the pegs.