Building or renovating your home and confused by the types of bricks available for purchase? Don't be. Buying and installing bricks for a variety of purposes is a satisfying and straight-forward DIY project. Depending on your needs, each type of brick offers its own aesthetic and structural integrity. There are four basic types of bricks to learn about before you begin your project: structural bricks, fire bricks, veneers and pavers.
Structural bricks are composed of various materials to achieve certain looks and properties. They come in a standard dimension of 3.5 X 2.25 X 8 inches, although other sizes are available. As the name implies, structural bricks give shape and strength to a building. In modern construction, however, bricks are typically added for aesthetic purposes, leaving wood, concrete and steel to do most of the heavy lifting.
One popular type of structural brick is called a calcium silicate brick. These bricks have a smooth finish on all sides and come in a variety of different colors, from deep red to pure white. Made from sand and lime, calcium silicate bricks offer only moderate water, fire and abrasion resistance.
But perhaps the most popular material for bricks is clay. Depending on how they are made, clay bricks can be extremely dense and capable of withstanding extreme conditions. Clay bricks made by hand will typically have an irregular (but attractive) face or outer surface, whereas bricks manufactured by a machine tend to have smooth faces. Clay bricks traditionally come in earth tones, reflecting their natural clay composition.
Installing structural bricks involves stacking the bricks between layers of mortar. Bricks are typically stacked onto a concrete foundation during the beginning stages of construction. Working in small sections at a time to avoid the mortar drying too quickly, a layer of mortar is troweled onto the existing bricks and new bricks are laid on top in a specific pattern (such as the "stretcher bond," in which bricks are offset with each row). The mortar is then wiped away from the joints before it dries, and the process continues.
Air bricks are a special subset of structural bricks. Instead of being solid, these bricks have about a dozen holes through their broad side. They are typically scattered through a building's foundation in order to promote air flow through a crawl space. This helps avoid moisture and heat build-up as well as slowing or preventing rot from invading the wood. They are installed like other structural bricks or embedded in a concrete foundation.
As the name implies, fire bricks withstand the intense heat inside kilns, ovens, fire pits, furnaces and fireplaces. They are clay-based bricks with a precise combination of silica and aluminum oxide that allows them to resist high temperatures.
If ordinary bricks are used in applications that call for fire bricks, the bricks will succumb to cracking and will absorb too much heat for effective cooking or heating capabilities. Firebricks often line the inside of a fireplace, but more attractive (and less expensive) clay bricks adorn the outside.
Fire bricks are installed in the same way as structural bricks.
Brick veneers give the outward appearance of brick without providing any structural support. They are for aesthetic purposes only and are about half an inch thick. Designers typically use brick veneers inside the home for accent walls or back splashes. However, they are suitable for some exterior projects, such as decorating a plain concrete foundation.
You can purchase veneers as individual bricks or mesh sheets. Individual bricks allow you to get creative with a design, but mesh sheets enable quick and easy installation with about 12 bricks attached in a pattern on each sheet.
Brick veneers are installed differently from other bricks. If you have experience installing tile, then installing brick veneers will be a piece of cake. Start with a tile adhesive designed for the surface you're working on (cement, drywall, wood, etc.) and trowel it on in a thin layer, working in small sections at a time. Firmly press the individual bricks or the mesh sheets onto the adhesive.
Once the adhesive dries, mix mortar according to the bag's instructions. For precise application, fill a mortar bag (which is like a large, heavy-duty pastry bag) about 3/4 of the way with mortar. Twist the top down and squeeze the mortar into the cracks. Again, work in small sections to ensure that the mortar does not dry before the next step.
Wipe away excess mortar with a jointer and use a paint brush to sweep over it a few times. Once the mortar dries, you can choose to give it a final finishing touch by applying a sealant.
Brick pavers come in dozens of shapes, sizes and colors, and are composed of a variety of materials, from clay to concrete (which can be dyed and molded to look exactly like clay bricks). These bricks have a flatter and more solid appearance than their structural counterparts and are made to be tough enough to endure plenty of foot traffic and other wear and tear.
Brick or concrete pavers typically create upscale patios, driveways, walkways and garden walls. Homeowners and builders choose brick or concrete pavers as an alternative to poured concrete for aesthetic and maintenance purposes. Poured concrete has a tendency to crack under certain conditions, but the joints that naturally exist between pavers reduce the tendency for such large cracks. When cracks do occur, it is simple to remove and replace only the damaged pavers.
Mortar is not required in order to install pavers, but a flat surface is a must. Start by covering a flattened area with crushed gravel or pea gravel to stabilize the surface and help keep weeds at bay. Smooth the surface as much as possible, then lay the brick pavers against each other very tightly. Once all the bricks are in place, cover the area with a layer of sand and sweep the sand into the joints. Repeat as necessary until all joints are filled.