The most sustainable way to build a structure is by renovating an existing one. This is the most eco-friendly option, but it still presents a host of challenges. The insulation typically needs to be installed if not upgraded, and the exterior walls often need to be revived. Instead of adding additional layers of heavy materials or doing a complete reclad, which increases the embodied and operational carbon of the building, construction stakeholders are selecting lightweight products that minimize carbon emissions, and also are less of a disturbance for the occupants of the buildings.
For the renovation of aging structures, lightweight EIFS assemblies are an ideal option. With EIFS, if the building has an existing brick or CMU exterior, contractors can overclad the structure by putting a liquid-applied weather barrier over the existing masonry, a layer of continuous insulation (ci), the application of a base coat and mesh, and then finally the finish that the customer desires. This is dubbed an overclad, and it can only be done with lightweight cladding.
The overclad method saves time and money for the owner funding the renovation and for the installation crews as well. It is also a much more sustainable option than demolishing a building, dealing with material waste, and expending considerable amounts of energy to construct a new one.
Another benefit is that if an existing exterior is already completed with EIFS, overcladding is still an option for the future because of how thin it is relatively to many other cladding options. For example, if a home or building has EIFS on it, but the owner decides they want to change the cladding to a wood alternative, they can simply install resin-cast wood over the EIFS. Both materials are lightweight, so the structural integrity of the building will not be compromised. This is an important consideration, because the thicker a wall gets, the more impact it has on other portions of the structure, such as the framing of the structure, windows, and doors. In sum, a wall can only be so thick. Therefore, thinner, lightweight claddings are advantageous for any potential building retrofits in the future.
Finally, repairs to an exterior are simpler with lightweight cladding systems such as EIFS. If there is a minor dent in an EIFS wall, an applicator can cut a section of the material out, fix it, and finish it without any visible inconsistency in the wall’s finish and without compromising the performance of the air, water, or thermal control layers. Compare this to having to replace a metal or fiber cement panel on a commercial building, where crews need to order a replacement panel, wait for it to ship, then uninstall the damaged panel and install the new one. This is more time consuming, and material production and transportation release more carbon into the atmosphere.
