A Guide To Exterior Insulation Finishing Systems

A Guide To Exterior Insulation Finishing Systems

Exterior insulation finishing systems first began to be used in the 1970s and have since largely replaced traditional three-coat stucco systems. These products provide homeowners with a variety of benefits, including energy efficiency and improved resale value. There are several options for insulating your home’s exterior, including EPS, drainage-free mineral wool, and Fiberglass mesh.


EPS is an exterior insulation finishing system that consists of a layer of foam insulation. The board is usually proprietary to a manufacturer and varies in thickness. Commonly, EPS is 3/4” thick with a maximum thickness of 4”. EPS boards are typically square-cut. Some manufacturers include mechanical fasteners, but these can act as thermal bridges and mirrors through the EIFS assembly.

EPS with drainage:

EPS with drainage is a popular choice for exterior insulation applications. EPS is a polystyrene foam material that can be applied over a variety of substrates. The board typically has a thickness of 3/4 inch, with maximum thicknesses of 4 inches. It is usually installed on a square-cut substrate. A variety of trowels are used to apply the insulation, with different sizes geared for different substrates. Three-quarter-inch-thick, U-notched trowels are commonly used for gypsum/wood sheathing, while a 5/8-inch square-notched trowel is used for concrete or masonry surfaces.

EPS with mineral wool:

In recent years, the use of EPS with mineral wool as exterior insulation finishing systems has increased significantly. These products are highly effective at providing both thermal insulation and water resistance. In addition, they are a cost-effective alternative to other construction materials. In addition, they offer flexibility in design and can help reduce air infiltration by as much as 55%.

Fiberglass mesh:

Fiberglass mesh is an innovative building material for exterior insulation. It is embedded into the base coat to reinforce the EIFS system and prevent cracking of the concrete. This mesh is flexible and easy to construct. It can also serve as a backing for tile, mosaics, backsplashes, and carpets. Fiberglass mesh rolls are 75 feet long and can be ordered in bulk quantities. Large orders are shipped via freight truck. There are two types of mesh: self-adhesive and adhesive.


Proper maintenance of exterior insulation and finishing systems is critical for their long-term performance. While they provide excellent waterproofing protection, these systems must also be cleaned regularly to prevent surface cracks and other problems. Even small cracks must be repaired, and the sealants reapplied periodically.