For relocating employees who are buying or selling a house within in the U.S., there’s another challenge they may face. We’ve been hearing about the challenges presented by composition board siding and exterior insulation and finish systems (commonly referred to as EIFS) for years. At the least, moisture issues can exist; at the worst, mold and structural deterioration of a house can occur due to improper installation.
Now, homeowners are encountering similar moisture and structural concerns with another siding material: stone veneer. Keep reading to make sure you’re in the know and able to help prevent any issues that may pop up for your relocating employees.
What’s the issue?
Stone veneer is appealing to builders and homeowners as a cost-effective alternative to authentic stone; however, if improperly installed, it can cause moisture issues and mold (more on that below!).
On properties that are going through a formal home sale process (i.e., BVO, GBO) during an employee relocation, an inspection should be performed on homes with stone veneer to determine if it was properly installed. If it wasn’t, the property may need further evaluation to determine if there is any structural damage to the property due to the improper installation.
As a result, the homeowner may be financially responsible for remedying the structural damage as well as the stone veneer in order to be eligible for the home sale process. Additionally, you might even consider eliminating these homes from the home sale program, consistent with the handling of homes with synthetic stucco or EIFS.
Home purchasers need to be aware of potential stone veneer issues and have the proper inspections conducted on a home they wish to purchase. Even if no issues are present at the time of inspection, you may want to warn the home purchaser that serious and costly structural damage may exist in the future.
As the problems associated with stone veneer become clearer, a home’s value and/or marketing time could be greatly impacted, as was the case with EIFS and composition board siding. Stone veneer is not a new product but one that has been on the market for a decade – but it is just now that we are discovering the long-term effects of improper installation.
So what exactly is stone veneer?
According to the International Association of Certified Home Inspectors, stone veneer is a lightweight, man-made concrete masonry product that is typically cast into random sizes in a variety of colors and finishes meant to mimic the look of quarried rock. It is generally applied as a masonry veneer to exterior and interior walls, columns and landscape structures. Thin stone veneer is lighter in weight, faster to install, and — in many cases — more economical to use than traditional, full-dimension stone veneer.
Stone veneer is also known as precast stone, simulated stone, manufactured stone veneer (MSV) and adhered concrete masonry veneer (ACMV). Cultured Stone®, a name that is sometimes used generically, is actually a masonry product manufactured by Owens Corning and is probably the most popular manufactured stone used in the U.S.
In most instances, the various names can be used interchangeably, but stone veneer is not synonymous with cast stone, which is a different product entirely. Cast stone is a refined architectural concrete building unit whose appearance is meant to simulate quarried stone, but it is generally built into a load-bearing masonry wall system. This is a different purpose from the lightweight stone veneer. These two products are manufactured according to different standards and are intended for different applications, although they are often confused with each other.
How is stone veneer often improperly installed, and what are the resulting problems?
As Lexicon’s service partner U.S. Inspect advises, concrete is porous and can absorb water as opposed to real quarried stone. This characteristic allows water to pass through the stone veneer and come directly in contact with the internal wall structure. Damage investigations often reveal that only one layer of building paper was installed, which is inadequate to protect the internal wall structure. Further, many installations lack proper details such as flashings, weep screeds and sealants designed to prevent water infiltration through the veneer, leaving the internal wall structure vulnerable to moisture damage.
Therefore, stone veneer must be installed with great attention to detail:
- Must have two layers of high grade building paper (only one layer is required with traditional masonry veneers that incorporate an air space between the material and the wall sheathing)
- Must have proper flashings over windows and doors
- Must have kick-out diverter flashings at roof-to-wall penetrations and other junctions where needed
- Weep screeds must be installed at the base of the wall as well as the tops of window and door openings
- Proper sealant details must be present where the stone veneer is in contact with another siding type
If any of this is neglected, the above issues may result. You can see how that could be common, since installation requires great care!
Here at Lexicon, we will continue to monitor the trends and issues with stone veneer and keep you informed. We always stay on top of such issues so we can provide guidance to our clients on how to structure and provide the best relocation benefits for them and their employees.