Can You Install Stone Veneer Over Brick?

Stone veneer fireplace

 

EricVega / Getty Images

If you have an uninspired brick fireplace or an interior brick interior wall that looks dated, you might be looking for ways to improve its appearance. Painting or staining your brick are two ways to give it a quick style refresh. Another option is to install stone veneer directly over the brick. Best of all, you can do this without ripping out the existing brick.

Preparing a Base for the Stone Veneer

In many ways, stone veneer is a better way than painting or staining to improve interior brick. It helps to bring your house up to date and increase its property value. None of the brick needs to be removed before you can install the stone veneer.

While you can install manufactured stone veneer over brick, it's not as easy as troweling mortar directly onto the brick and applying the stone veneer. As with other surfaces, the brick must provide a stable surface for the veneer layer.

One method starts with a wet scratch coat that's applied to the brick before you install the veneer. Another method avoids the scratch coat and uses cement board instead. Essentially, the cement board becomes the scratch coat.

Scratch Coat

A scratch coat is a rough coat of mortar that provides a firm, porous surface for the veneer to stick to.

How to Apply Stone Veneer to Brick With a Scratch Coat

Avoid applying the scratch coat directly to painted brick. Painted brick will not accept the scratch coat because the brick surface is not porous.

This does not mean that all unpainted brick is perfect, though. Smooth-surfaced brick or very crumbly brick still are not appropriate for a scratch coat and must be repaired first.

  1. Prepare Brick Surface: Sand- or water-blast the paint, dirt, or oils so that you have a raw, fresh, porous (but not crumbling) surface. Some masons say that this is an adequate surface for accepting a scratch coat.
  2. Install Metal Lath: Metal lath is an acceptable surface that will allow you to apply veneer to brick. First, apply corrosion-free 18-gauge metal lath to the brick with masonry fasteners. Make sure that the cups of the lath are pointing upward (think of the abrasive surface of a cheese grater). Overlap both the horizontal and vertical seams by 1 inch. Be sure to wrap the lath around corners (both inside and outside) rather than applying two separate pieces of lath. This gives the framework more stability.
  3. Apply Mortar: The scratch coat of mortar is troweled over the metal lath. Be sure to force the mortar through the holes of the lath. Trowel the top of the mortar smooth to accept the veneer stone.

How to Apply Stone Veneer to Brick With Cement Board

For do-it-yourselfers, a often better option is to install a layer of cement board over the brick, then install the veneer on the cement board. This serves the same purpose as the scratch coat but, in some ways, is better.

The cement board is already hard and flat even before you apply it to the brick. With a scratch coat, you need to work the surface with a trowel to flatten the mortar.

The cement board works essentially like the metal lath and mortar method, but installation is cleaner and allows you to begin veneering immediately.

Cement board is screwed or nailed to the brick, acting as a new underlayment and bypassing the brick. Most professionals recommend mortaring down the cement board on the brick. The cement board can even bridge over some minor gaps, cracks, and imperfections in the brick.

Finally, a mortar layer is applied to allow the manufactured stone veneer to stick to the cement board. You'll need to press each stone firmly into the mortar for several seconds for it to properly stick.

Type of Stone Veneer to Use

Manufactured Stone Veneer

The choice of most amateur masons, manufactured stone veneer is made from Portland cement, aggregates and iron oxide pigments.

Cultured stone or artificial stone are other names given to this product that looks much like the real stone (Cultured Stone is a trademark of Boral Stone Products LLC).

Manufactured stone veneer is heavier and more substantial than polymer faux panels, but not as heavy as real stone. It comes in individual stones that you fit together piece by piece and mortar onto the wall, just like real stone.

Stone veneer diameters range from 2 inches to 30 inches and have an average wall thickness of 1-3/4 inches.

Natural Stone Veneer

Natural stone veneer is carved from the Earth, beautiful, heavy, and difficult to work with.

Natural stone veneer is available only from stone yards and can be expensive. However, natural stone can be workable when sliced into a thin veneer in the factory. This makes the stone lighter and easier to handle.

Natural stone veneer is not common, but it is the most accurate and realistic form of stone veneer you can purchase.

Faux Stone

Faux stone has no stone products in it at all. It is a high-density polyurethane and usually comes in panels, rather than individual stones, for quicker installation.

Many faux stone products are cast in the shapes of real stones, so they are quite realistic. The similarity ends when you rap on faux stone with your knuckles—it feels hollow and lightweight.

One advantage of faux stone is that brick surface preparation is minimal. No lath or scratch coats are required. You can even apply faux stone to painted brick.