Air Barriers

Air Barriers, Air Barrier Systems, Green Building, Energy Consultant, Passtionate Green Builder, Energy Auditor, Energy-Efficient Homes, DFW, Dallas, Texas, Fort Worth, TexasPlease Note:This website explains green building for a climate zone comparable to North Central Texas, such as the climate of Arlington or Addison, Texas, or Dallas-Fort Worth, Texas. It is important to hire an energy consultant and a green builder who are experts in energy-efficient building in your climate zone.

Air-Barriers in Green Building

 

The Control of Air Flow

 

 

Note: This website is for the climate zone that includes North Central Texas such as the DFW area or Colleyville or McKinney, Texas. Regardless of your climate zone, the first priority for green building or energy-efficient remodeling is to hire an energy consultant and a green builder  who understand and use up-to-date green building practices for your area.

 

Air Barrier
The primary function of an air barrier is to control air flow between a conditioned space and an unconditioned space. Many performance problems of homes can be traced to air leakage through the building envelope. These problems include everything from high heating/cooling costs to poor temperature control in occupied spaces. The air barrier is a very important aspect of green building.  

Air Barrier Materials  

Air barrier materials are defined by their air permeance. Air barrier materials are combined with air barrier components to form air barrier assemblies. These assemblies are then connected to form complete air barrier systems. Air barrier material types for green homes include: 

Self-Adhered Sheet Materials  
Fluid Applied Materials
     Liquid Applied Materials
     Spray Foam
Mechanically Fastened
     Board Stock Materials
     Film Materials
Thermofusable Materials  

Air Barrier Systems
Air barrier systems consist of numerous materials which areassembled to provide a complete barrier to air leakage through all six sides of the building enclosure. They control the movement of air in and out of buildings. The air barrier system is the primary air enclosure boundary that separates indoor, conditioned air from outdoor, unconditioned air. 

This system essentially“wraps” the shell of the home and protects it fromthe effects of air leakage. Air leakage can have detrimental effects on how ahome functions and even reduces the life span of the structure. Air leakage mustbe reduced in a green home.

A properly functioning air barrier system provides a barrier against both theair leakage and the diffusion of air caused by 

  • Wind Pressure
  • Stack Pressure (sometimes called chimney effect or buoyancy)
  • HVAC Fan Pressure, although this is not a particularly important problem in warm climates like the Dallas-Fort Worth.

Air barrier systems also typically define the location of the pressure boundary of the building location. In multi-unit construction such as townhouse/apartment units, the air barrier system separates the conditioned air from any given unit and its adjacent unit or units. It is also the fire barrier and the smoke barrier which separates units and must meet the fire-rating requirements.  

There are many types of air barriers to choose from, and there are many important factors to consider when determining the best barrier for a green building. The complete air barrier system is comprised of materials and assemblies, each with their own performance requirements.

A well-designed and efficient air barrier system will:

  • Be impervious to air flow,  thus controlling air infiltration and exfiltration.
  • Maintain constant air pressure.
  • Be continuous over the entire building envelope or continuous over the enclosure of any given unit in multi-family construction.
  • Reduce HVAC systems.
  • Reduce home energy consumption
  • Control moisture within the building envelope.
  • Prohibit the growth of mold.
  • Reduce harmful air pollutants.
  • Protect the health of the home’s  occupants.
  • Be durable during construction.
  • Be durable over the lifetime of the home.
  • Lower noise coming from outside the home.
  • Will make all components, including light fixtures, airtight when installed through the air barrier.

One way to test the effectiveness of the air barrier system is with a portable pressurization fan which is also known as the "door rater" test or "blower door" test. This test is generally the first step in renovating a home for energy-efficiency.

In summary, air barrier systems are essential components of the home enclosure. They control concentrated condensation and the associated mold,corrosion, or rot, they improve durability & sustainability, and they allow reduction of the HVAC system when the"fudge factor" covering infiltration and other unknown factors is reduced or eliminated.

Do you need an energy consult
or energy audit or
green builder/remodeler
in North Central Texas
or the Dallas-Fort Worth area?
Contact Terry Jensen
Frugal Energy, LLC
817 443-2553 or 972 251-1532

 

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Note: The opinions expressedherein are exclusively those of the writers or other participants and do not necessarily reflect theposition of CyberParent,LLC. They are not intended to take the place of advice of ahealth, legal, or other professional whose expertise you might need to seek.This website explains green building and green remodeling for a climate zonecomparable to North Central Texas or Dallas-Fort Worth, Texas,  It isimportant to hire a green builder and an energy consultant who are experts inenergy-efficient building in your climate zone and who use the most up-to-dategreen building information.