EIFS is an Exterior Insulation and Finish System. Some people call it synthetic stucco. It's made of lightweight, two-inch thick polystyrene panels with an acrylic coating that mimics traditional stucco. It’s a good idea to keep an eye on how it's holding up. Moisture that gets in through poorly caulked joints or surface punctures can get trapped and cause the framing and plywood sheathing underneath to rot, leading to costly repairs. With knowledge and proper maintenance you can prevent water and moisture damage from adversely affecting your synthetic siding.
Lightly knock on the surface. EIFS sounds hollow while traditional stucco is solid. Press lightly on the surface. EIFS gives slightly while real stucco is very hard. EIFS exteriors have caulking, while real stucco exteriors do not. And if you can place your hand under and behind the bottom edge it's probably EIFS. Don't ignore synthetic stucco used as a decorative element. EIFS always needs to be installed and maintained as if it were used to side the entire house.
Regular inspection is important to making sure seams are intact and the surface hasn't been damaged. Always check after a windstorm as tree limbs may dent or pierce the siding. Woodpeckers can also create holes that will let water in. And you should never attach anything to this siding that punctures the surface, such as mailboxes, hose holders, street numbers or planter boxes.
EIFS should not contact the ground or another surface where water accumulates. This could allow moisture to be absorbed through the bottom of the wall. Certain brands of siding may call for specific repair techniques. Don't hesitate to call a professional if they seem beyond your comfort level.
EIFS is not a do-it-yourself type of project. Proper installation is critical to the siding's performance. To qualify for a warranty make sure that the installer is certified by the manufacturer to install their product.