Masonry Magazine April 2010 Page. 24
The usage of fluid-applied air barriers has become more prevalent as modern construction technology develops. When properly installed in conjunction with self-adhesive tapes, even small gaps are eliminated, providing total continuity of the air barrier.
Air Barriers: An Evolution
# By Christopher Bupp
The building envelope has become the focal point of architects, engineers and consultants during the very recent past. The wall assembly is now viewed with the same scrutiny that roofing systems have experienced for many years. In order to make a building energy efficient and to control moisture infiltration, air/vapor barriers are commonplace on almost all commercial structures today. Increasing awareness of the importance of the building envelope has occurred due to reports such as the United States Department of Energy's conclusion that up to 40 percent of energy needed to heat and cool a building is lost from air leakage. State building codes typically reference or adopt ASHRAE Standard 90.1 Energy Standard for Buildings Except Low-Rise Residential Buildings.
As with any other product or business, the air/vapor barrier business continues to evolve from its earliest forms of black tar paper found behind stucco systems, and siding in older residential homes. Roofing felt paper was used in residential and commercial construction for a number of years with varying degrees of success. The next step in the evolution was the use of building wraps that were more durable than roofing felts. Today's building wrap systems include detailing tapes for laps plus window and door openings to create an airtight barrier.
As the industry continues to mature, commercial construction has seen a dramatic growth in the use of fluid-applied barriers along with self-adhesive detail tapes. These types of barriers have distinct advantages over previous materials, with the ability to provide total continuity of the barrier, as we know even the smallest of gaps can significantly affect performance. The newer fluid-applied materials provide a "structural" building envelope barrier with continuous contact to the substrate capable of resisting forces from wind, mechanical pressurization and stack effect. One of the challenges associated with fluid-applied products is the ability to control application thickness, but with more contractors becoming experienced installing the fluid-applied systems, that concern seems to be diminishing.