What is the difference between traditional and synthetic stucco?

What is the difference between traditional and synthetic stucco? Now traditional stucco siding is made from Portland cement, sand, lime, and water, and the mixture is applied over three in three coats over a mesh. Synthetic stucco is multilayered with a foam insulation board, a coat of synthetic stucco, fiberglass mesh, and then a top coat. If you have stucco walls and you're unsure of whether they're traditional or synthetic stucco, it's no surprise the two look almost identical. The simple way to determine what you have is to push on the wall or knock on it. Traditional stucco will be rigid, while synthetic stucco will be a little bit softer and sound hollow if you knock. Also, if there's a light fixture event or a hole and you're able to see the layering, if there's a wire mesh, it's traditional stucco. If there's a foam core, then it's synthetic stucco.