Masonry Magazine July 2009 Page. 34
AIR BARRIERS
Each type of air barrier product has specific characteristics that may provide benefits over another type for certain projects or climates; this very topic is grounds for another article unto itself.
Briefly, key design considerations in specifying the appropriate product include:
* The type of construction materials being used (e.g., brick cladding and CMU backup)
* Overall climate for the given location and temperature during installation
* Compatibility of the materials being used
* Timeframe for construction completion
* Product durability
* Efficient application
* Code compliance.
"From an installation standpoint, it really depends on the type of application as to which product makes sense," Bupp says. "Also, with the different climates that we have in the United States, it really has to be determined by geographical area what types of products work best in any given application. I wouldn't tell an architect firm in San Antonio, Texas, to apply a vapor barrier in the same area of a wall system as I would for a firm in Boston. Most designers understand that, but I still think it's important to stress"
If there is any doubt as to the appropriate material to choose for a particular project, your air barrier manufacturer can assist you in specifying the correct product.
Going green
NOT ONLY DO AIR BARRIERS make sense in creating a healthier environment by limiting the potential for moisture-related problems, but they are also a great addition to a building's overall sustainable design. Masonry buildings already provide significant energy and lifecycle savings, but air barriers are an additional improvement to both of these areas for owners and occupants.
The U.S. Department of Energy determined that 40 percent of the energy consumed to heat or cool a building is due to air leakage. However, according to a 2006 National Institute of Standards and Technology study, a properly specified and installed air barrier system can provide an energy cost savings of approximately 32 to 39 percent, with the largest savings going to buildings in colder climates. Also, due to this significant energy efficiency capability, air barriers can provide points toward a building's LEED certification.
In addition, air barrier products themselves are getting greener, such as Hohmann and Barnard's TextroFlash™ Green, a multi-purpose, flexible, self-adhered membrane manufactured from 45 percent recycled content, and TextroFlash™ Liquid, a VOC- and HAPS-free liquid air-vapor barrier.
Basic installation steps
JUST AS WELL RESEARCHED and exact designs and specifications are important to the successful implementation of an air barrier system for any given project, installation is equally important for the overall satisfactory completion.