It's easy for small amounts of water to enter a home's wall cavity, both during and after construction. When water evaporates it becomes a gas (water vapor) that needs to escape. If the walls can't completely dry, a home is more likely to experience mold and rot.
A building material’s ability to let water vapor pass through is called permeance, measured in units called “perms.” There are two ways that the American Society of Testing and Materials (ASTM) measures permeance in its E96 test: Procedure A (desiccant or “dry cup” method) and Procedure B (water cup or “wet cup” method).
Here are some common misconceptions about building enclosure performance and the truths behind them:
TRUTH: “Whether a vapor-control material is 5 perms or 35 perms, the drying rate is usually limited by other materials like the cladding,” says John Straube, a principal at RDH Building Science and an associate professor at the School of Architecture at the University of Waterloo in Canada.
TRUTH: “The house wrap industry emphasizes the ASTM E96 Procedure A or ‘dry cup’ test,” adds Straube. “But the test that’s more appropriate for in-service use of wood-framed buildings is really Procedure B or the ‘wet cup’ test. I have a colleague who says, ‘Procedure A measures how much water vapor passes through when there isn’t any water vapor, while Procedure B measures how much passes through when there is water vapor.’”
TRUTH: It defeats the purpose of an air/water barrier if a home’s exterior flashing isn’t done properly. “There are far greater mold risks when sheathing gets wet after the home is occupied than when it’s being built,” says Straube. “If windows leak into the wall, that’s really scary because you can’t see it.”
Learn more about the LP WeatherLogic™Air & Water Barrier system, the latest addition to LP’s portfolio of structural solutions.
There are only two ways to boost your bottom line: increase revenue and cut costs. In this blog, we'll explore innovative ways for builders to cut costs in order to increase homebuilder profit margins - and we'll examine revenue enhancement in a future post.Continue Reading
According to the latest American Community Survey from the U.S. Census Bureau, about 4 million people now work in residential construction (both single-family and multifamily) - down from the 5 million who were employed just before the Great Recession. Although the workforce has shrunk by 20 percent nationwide, some parts of the country are experiencing less pain than others. Similarly, light commercial construction has been reportedly back on the rise post-Recession, with IBISWorld reporting that the recovery started just before 2014 and continuing steadily through 2019 (source).
It's frustrating when factors outside of your control cause you delays or unexpected expenses during a project. Those factors could be weather delays, insufficient staffing, breakdowns in cash flow and unreliable product availability. LP devotes significant resources each year to ensure that its product availability is second to none. Because even the most innovative building solution is useless to customers unless they know that it's available when they really need it.
It's a silly name, but a "butt joint" is an application technique where two pieces of material are "butted" up against each other. It is the simplest joint to make, and a butt joint can be either end to end or end to face. Depending on the width of the wall, butt joints will occur where two pieces of lap siding come together, creating a vertical seam. LP® SmartSide® lap siding products are available in 16' lengths, and can help reduce the amount of seams where a butt joint would normally occur when using shorter pieces.