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  • Writer's pictureJessica Foster

How Wall Coverings Keep Water Out

The walls of any renovation project are a crucial structure, with multiple functions and different parts, such as wall covering. An important aspect of wall coverings, both interior and exterior, is keeping water out of where it doesn’t belong. Interior covering can be made of a variety of materials but all need to be a certain standard to ensure water is kept away from vulnerabilities in the house, such as areas near showers/tubs. Meanwhile, exterior wall coverings should be constructed in a way to keep rainwater from entering the building. The International Residential Code has minimum regulations to ensure both interior and exterior wall coverings can provide water resistance.

For interior coverings, backer boards placed in tub and shower areas must meet the IRC’s minimum requirements to ensure water resistance to keep out mold and mildew. Backer boards are a substrate material for tile.The necessary quality for the type of material used to construct a backer board are given by the IRC, with manufacturers rating their own products to IRC standard. By following these guidelines, the backer board can help keep water in the tub or shower, reducing water damage and displacement.

Exterior wall coverings are subjected to outside forces such as weather, and protecting vulnerable spots of the house from wind-driven rain is one of their crucial functions. Flashing is installed as a thin sheet to act as a barrier, keeping water away. The flashing must be corrosion-resistant and approved by IRC standards to keep water from entering into the wall cavity or the building’s structural framing. Where flashing must be installed is dictated by the IRC, with locations such as at exterior windows/door openings, intersections of chimneys, where porches/decks attach to a wall, wall and roof intersections, gutters, and so on. For fenestration such as doors and windows, the manufacturer can have their own flashing installation process that should be followed when using their products.

Water-resistant barriers are utilized in both interior and exterior coverings to further contribute to keeping water out. The IRC calls for a layer of No. 15 asphalt felt to be applied over studs/sheathing of all exterior walls. The felt must be placed horizontally, with the upper layer lapping the lower layer no less than 2 inches. This design choices helps close off the structure from wind-driven rain. Other approved materials aside from asphalt felt can be used but must be installed adhering to the guidelines of their manufacturers. Regardless of the approved material, it all must serve the same function as being a water-resistant barrier.

Ultimately, exterior and interior coverings share a goal of keeping water out of the wall cavity. This is achieved through the IRC having different standards based on what material is used as the covering, so the wall covering keeps water out. This function is heavily integrated in every design choice when it comes to siding, as the top piece will overlap the bottom piece in order to be water-resistant. Though different types of siding exist, all of them strive towards this function of keeping water away. Here at Fine Remodeling, we are your Delaware contractor experienced with the different requirements based on varying wall covering materials and how to install them. We are dedicated to making sure that your wall coverings not only meet the IRC standard, but go even beyond so that your remodeling project is more than just safe and satisfactory. Call to review your next project with us so you can be sure it’s done right the first time.

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