Stone Veneer Problems: The inside story to manufactured stone siding

Popular and attractive, but not without its issues, Manufactured Stone Veneer, or Siding Adhered Concrete Masonry Veneer, is a thin siding, manufactured from molded concrete, to mimic the look of natural rocks and stone. Designed to be installed over wood framing, stone veneer can give a modern look to any home. However, stone veneer problems quickly arose a few years after the early installations.

The material gained popularity in the late 1990s and early 2000s as a replacement for real stone siding which was difficult and expensive to install. As with most newer siding products, the procedures of installation have changed and improved over the years. However, the basis is the same. Stone pieces are arranged together and adhered to the side of a home using mortar.

Much like brick veneer, the structure behind the stones is typically a wood framed wall. Because of this, if the stone veneer is not installed properly, it could allow moisture to intrude behind the material to the wood framing where it can impact the structure of your home.

How do stone veneer problems occur?

Manufactured stone veneer is typically installed on top of the wood sheathing on a house or over house wrap. Because mortar and cement are permeable, over time water can seep behind the material. Similar to the issues with EIFS stucco, if water penetrates the material and has nowhere to go, stone veneer problems begin to occur. Water makes its way to the substrate of the wall and begins to cause moisture damage and mold on the organic wood below. Basically, once water gets behind the veneer, then the enemy is within.

But, builders are still installing this material with increasing frequency? What gives?

Well, as I stated before, installation methods change and builders and manufacturers learn from the past. Thankfully that solution to this issue was already discovered in the stucco world. If water gets behind a material, the best solution is to give it a nice path out. Because of this, most newer installation methods implement drainage requirements.

Kick out flashing at the top edge of the material and a drainage plane for water to make its way out are now required on all installs. This is very similar to a hard coat stucco installation. A weep screed will be placed at the bottom edge to keep installers from sealing the bottom edge of the material and drainage mats that create air gaps help create a pathway for water to escape.

All of this has made stone veneer an acceptable and beautiful product to use on a home. But there must be a path created for moisture to drain and escape. Failing to do so can cause stone veneer problems.

But what about the older houses?

Here lies the root of the most well-known building issues. Whether it be asbestos, EIFS stucco, lead piping, aluminum wiring, FPE electrical panels, etc, etc, etc…

Before anyone realized the flaws that new building designs had, there were years and sometimes decades of time where these installations were standard and common. This leaves hundreds of thousands of houses with improperly installed stone veneer with the potential for moisture concerns.

Luckily, if you live in Colorado like us, the dry climate can dry out the material quickly, and the number of stone veneer problem cases in our state is very low. More humid environments have seen further issues where the product had to be repaired. But as we have seen with EIFS, no one is completely safe.

During our home inspections, we look for tell tale signs of water intrusion in the product. This ranges from cracking, to loose stones, to efflorescence. We can also take an even deeper look with our moisture inspections. This inspection is designed to look at stucco, but our EIFS stucco inspection can cross over to stone and potentially help determine whether any moisture issues are present.

Be on the lookout for these issues on your home or the home you intend to buy. It can save you a lot of money and heartache in the long run.