Installing Stone Veneer over a Metal Substrate
In just the past couple days we’ve heard from a handful of our clients and some of the installers that are working with our stone veneer products about how the product can be installed over a metal substrate. There is actually a couple different ways to approach this type of installation, and metal actually shows up more often than you’d think as a substrate. So let’s take a look at how stone veneer can be installed over metal substrates.
In terms of the types of projects that you see metal projects on, almost all of the folks we’ve talked to recently have been working on fireplaces, which is a popular project at this time of the year as we’re all getting ready for winter and to start cranking up those fireplaces for heat very soon. Most often the fireplace insert is going to have a metal flange, similar to a window, that extends out along the wall that the fireplace is mounted on and that provides vertical anchoring points for the unit. These flanges can vary in how far they extend out from barely two or three inches, to several inches. Fireplace units with larger flanges are the ones where a different form of adhesive needs to be considered. If the flange only sticks out an inch or two, and the overwhelming bulk of a stone veneer unit or natural stone tile is going to be adhered directly to the masonry wall substrate (block, brick, cement board, etc), then extra consideration about adhering stone to the metal substrate is probably not necessary.
Other metal applications that we tend to see natural stone being used on are exterior applications of prefab buildings which often have exterior steel shells. Our natural stone products have been used as a decorative top layer on prefab buildings of all kinds, including marinas, warehouse/industrial space, and even prefab railway sheds that sit along train lines in remote areas to house control and safety equipment. More often than not, the metal building is in place for a very practical reason, especially since metal buildings can be cost effective to construct, and then the stone comes along later in an effort to spruce up the overall look of the space.
Another very common application is prefabricated outdoor kitchens and grills islands, which often can ship straight from the manufacturer preassembled with a metal outer layer that can be clad with stone, or a variety of other materials.
As far as the actual installation of stone veneer over metal substrates, we recommend two different methods. With either method, the first step is making sure the surface is clean of any contamination, such as dirt, rust, paint, etc. Pressure washing and sand blasting are effective techniques to get a clean metal substrate.
Once the metal substrate is clean your two options for installing stone veneer are to either tack weld a wire lathe to the steel and then build out that layer with thick bed mortar mix, which will set and then the stone veneer can be applied to using a traditional cementious based thinset. An alternative option that eliminates the metal lathe and scratch coat is apply the stone veneer directly to the metal substrate using an epoxy based tile adhesive. Be sure to talk to the manufacturer of the stone, or a sales rep with good knowledge of tile setting materials for a specific recommendation on the epoxy adhesive to use. Set the stone veneer using the epoxy adhesive according to the instructions of the adhesive manufacturer, and if you have any of the epoxy adhesive left over, you can likely use it up over other more standard substrates since epoxy adhesives adhere to almost any type of substrate.
We’ve been fortunate enough to work on a lot of unique and different installation processes with our clients having operated Norstone over the past decade plus and seeing millions of square feet of stone veneer get sold and installed. Installations over metal substrates is just one example of a unique condition that a product like stone veneer can easily adapt to. If you have a unique installation condition you are considering stone veneer for, please don’t hesitate to contact our sales and technical teams for more information on how stone veneer can be successfully used on just about any project.