If you’ve decided to design with stone, you’ve no doubt done your homework and selected the best quality stone veneer products and accessories to realize your design dreams. But there’s still some important legwork left to do. Even if you chose a top-of-the-line product, if your walls aren’t correctly prepared, or if the material is not installed correctly, your new stone won’t look correct. Here's how to avoid the fear factor and make sure you understand the preparation and steps your installer will need to go through to do the job right.
Here is an overview of the steps involved in installing stone veneer to help you understand the process. Homeowners who are skilled at remodeling projects may feel comfortable installing stone on smaller projects themselves. Here is an overview of the basic steps. Remember, the installation manual should always be read in detail before beginning a project.
*Most styles are sold in boxes of 10 square feet of coverage with a half inch mortar joint. Drystack applications will yield 8.5 square feet of coverage. True Stack cartons cover 10 square feet with no mortar joint.
Your installer will measure the linear feet of corners needed, as well as the square footage of each wall for flat stones. To arrive at the total square footage of flat stones needed, he will subtract the square footage of any openings like windows, as well as the linear footage of the corners. To compensate for jobsite waste, he will order at least 10% more than the final square footage. He will also determine how much premix mortar or mortar and masonry sand are needed for the project.
Preparing the walls is key to a quality application, and a weather-resistive barrier is a requirement for both interior and exterior applications. This consists of a Weather-Resistive Barrier (WRB) of #15 felt (one layer for inside applications, two coats for exterior applications), metal wire lath and a scratch coat of pre-mix mortar like Quickcrete or type S or N mortar. When these are installed, the scratch coat is left to dry for 24-48 hours.
Once the walls are prepared, it’s time to apply the stone. Your installer will lay out stones from multiple boxes to ensure the broadest range of stones for variety and a lower repeat rate. The corner stones are usually applied first, alternating long and short sides. Next, the flat stones are applied on the wall, working them into the corners. Stones are applied by adding mortar to the back and wiggling them onto the dry scratch coat. To fit stones into the space, your installer will size them as necessary using anything from a wet saw to a chisel or back of a hammer.
To finish the look, after the stones are on the wall, your installer will go back and add a mortar joint in between stones for non-dry stack applications. For a standard joint, as you would see with a Fieldstone style, for instance, the installer uses a grout bag to add mortar in the space between stones. When the mortar is thumbprint dry, a pointing tool is used to smooth out the spaces. Drystack applications are designed to show no visible mortar joint between stones. For more information on grouting styles,