Adhered Manufactured Stone Veneer (AMSV)
You’re buying a home and it has Adhered Manufactured Stone Veneer (AMSV). What do you know about it? Better yet, what does your home inspector know about it?
The first thing you should know is the local building department doesn’t inspect it – not during installation and not at final. Chances are, no one has inspected it.
The second thing you should know is if the veneer looks like this picture, you have a problem; and it could become an expensive problem when moisture is trapped behind the stone veneer.
AMSV is a lightweight, non-load-bearing masonry cladding that simulates the appearance of natural stone or brick. It is applied like stucco over different types of rigid sheathing. The sheathing can be gypsum, plywood, or oriented strand board (OSB). Best practices call for two layers of water-resistant barrier (WRB), metal lath secured to the framing with corrosion-resistant fasteners, and a scratch coat and mortar setting bed.
Sadly, few builders or installers follow best practices during the installation of AMSV. We often find installers omitted the scratch coat and lath and the AMSV was installed onto a thin mortar bed without back buttering the stone. We refer to this as a “lick and stick” application. Drip edges on top of the stone and weep screed at the bottom are also often omitted along with proper grouting of the stone.
AMSV should be installed in compliance with ASTM C1780, Standard Practice for Installation Methods for Cement-based Adhered Masonry Veneer, and Florida Building Code – Wall Coverings (which incidentally includes best practices for controlling moisture). The National Concrete Masonry Association (NCMA) also publishes the Installation Guide and Detailing Options for Compliance to ASTM C1780 (5th Ed). Sadly, few building officials inspect wall claddings for compliance due to budget constraints. This is left to the builder who leaves it to their subcontractor who often assigns the work to minimally qualified workers.
AMSV is a long-lasting, attractive product that compliments the façade of most homes and like any wall cladding product, it requires competent installation practices. If you are buying a home with AMSV, carefully look at the stone/brick. Are corners capped or do you see grout lines on corners? We often find the subcontractor failed to order corner pieces, so they tie the stones together at corners using grout (which is porous). Now, while a true stonemason can do this and make it look good, this practice would require additional flashing (metal or membrane) at the corners, and I have yet to see this performed. Corner pieces and true stonemasons are costly, so they are mostly omitted in production building. I know, the home cost you $650,000 but you should know it is still a production home. The site development cost along with the builder/developer profit cost you half of what you paid so again; understand you have a $350,000 home on an expensive lot.
Moisture-wicking or pooling behind the AMSV will cause damage to your structure. On average, the evidence becomes apparent in 5-8 years after installation, but we have found moisture inside homes in as little as one year. Often the homeowner notices water staining on an interior wall or water entering below baseboards. Wet walls are also attractive to termites, cockroaches, ants, silverfish, and earwigs. Repairing faulty AMSV can be expensive, and it may not be covered by homeowners insurance which typically does not cover construction defects related to workmanship or materials. Regardless, you would most likely need the services of a good lawyer to pursue coverage, and construction defect claims can be very expensive and take years to resolve. Meanwhile, your home is rotting. You should also understand your recourse against the builder may be minimal, if at all. That would also require the services of a good lawyer.
Homebuyers are encouraged to hire a home inspector when buying a resale home but not as much when buying a new construction home. You’re told the builder provides a warranty on the new home. They do, but the devil is in the details and that warranty may not make you whole. In fact, it may just kick the can down the road for you to deal with later.
Even when homebuyers have the home inspected, oddly enough most home inspectors have no clue how to inspect AMSV or stucco. They don’t have to as their liability is limited to what is “visual” and their inspection is a “snapshot in time”. I know you tried to protect yourself, but you just didn’t know the inspector had no specialized training in AMSV or stucco or any background in home construction. Again, they don’t have to have any background in building construction to get a home inspector license. I know, your realtor referred them, but your realtor doesn’t have to know anything about home inspections to refer a home inspector. They generally refer who they like, who supports their office, who is cheaper, or who reports the way they like. Real estate agents rarely refer the most qualified inspector. If you are buying a home with AMSV or stucco and your agent refers an inspector with no real qualifications or experience in these products, maybe you should ask them why they are referring them.
Hire An Experienced Home Inspector
If you are buying a home with stone/brick veneer, stucco, or EIFS wall claddings, you should hire a home inspector with specific knowledge and experience in these products. As a minimum, the inspector should be Level II qualified by the Exterior Design Institute for inspection of EIFS/Stucco/AMSV. Ask for the inspector’s credentials. An inspector who also has certification as a General Contractor or Building Inspector is a big plus.
Property360 provides certified inspections of EIFS/stucco and stone/brick veneer wall claddings in the metro Jacksonville and Orlando, Florida regions. We provide forensic moisture, mold, and termite investigations throughout the State of Florida. For additional information or to request an inspection, please contact us at (904) 606-1570 today!