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Business Advice5 min

The Importance Of Vapor Permeability In Building Envelopes

Since 1898, the American Society for Testing and Materials (now called ASTM International) has developed technical standards for a wide variety of building materials. They test for things like burn resistance. For weather-resistant barriers (WRBs), ASTM has developed rigorous tests for water resistance and water penetration, plus an air barrier assembly test. But an equally important test is ASTM E96, which measures water vapor permeability over a 24-hour period.

Even after exterior cladding goes up, walls can get wet. Small amounts of moisture in the wall turn to gas (water vapor) that needs to escape. If walls can't dry out thoroughly, the home is susceptible to mold and rot.

The term vapor permeability (sometimes called "breathability") refers to a material's ability to let water vapor pass through it. ASTM E96 measures this in units called "perms" - and today's building codes require WRBs to provide 5 perms or higher.

The Difference Between House Wrap and WRB

Since the 1960s, many builders have relied on plastic house wraps to achieve superior vapor permeability. But house wraps are applied after traditional sheathing is installed and approved by code officials. Then a crew has to return to wrap and tape the whole house.

In contrast, a product like new LP WeatherLogic Air & Water Barrier requires fewer steps. The sheathing and weather-protective layer are combined in a single panel that can be installed just like regular sheathing. The panel seams are then securely taped with an advanced acrylic tape that features one of today’s highest quality adhesives. And because the vapor-permeable overlay is permanently integrated into the panel, it won’t tear or blow away.

One of the best ways to get a tight building envelope is to use a structural panel like LP WeatherLogic barrier where the sheathing and vapor-permeable layer are tightly bonded during the manufacturing process. It's a breakthrough that involves fewer steps and less waiting than using house wrap.

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Business Advice4 min

FIRE-RATED SHEATHING INSTALLATION: SOFFIT & EAVE DETAILS

When it comes to how to install fire-rated OSB sheathing, ensuring the soffit and eave details are aligned with code requirements can be a challenge. Here, we'll take a look at two methods that can help you install this part of your wall assembly accurately and in line with codes for fire resistance.

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Business Advice4 min
ENERGY-EFFICIENT BUILDING MATERIALS FOR HOT CLIMATES

In hot climates, energy efficiency can be a top concern for homeowners. Increased needs for cooling alone can lead to higher energy costs, so builders and homeowners alike are typically on the lookout for ways to mitigate energy spend and create energy-efficient house designs for hot climates.

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YOUR GUIDE TO LP® SMARTSIDE® EXPERTFINISH® TRIM & SIDING ACCESSORY PRODUCTS

Available in 16 prefinished colors, LP® SmartSide® ExpertFinish® Trim & Siding can help you bring greater efficiency to your builds alongside a look your clients are sure to love. But did you know the LP SmartSide ExpertFinish collection includes more than typical siding materials?

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Better Together: Add Strength to Your Sub-Floor System with LP Legacy® Products

When it comes to sub-floor systems, building with products designed to complement one another is critical for a smooth project. That's why LP's powerful pair of sub-flooring products, LP Legacy® Premium Sub-Flooring and LP Legacy Premium Sub-Floor Adhesive, offer a great solution to any sub-flooring project.