Air Barrier

Energy Efficient Air Barrier

Stop air leakage and maximize energy efficiency.

Air leakage is one of the most significant causes of energy loss, because it works against expensive heating and cooling equipment by disrupting inside temperature. By forming a continuous, rigid air barrier, ZIP System® Roof and Wall Sheathing reduces air leakage, while outperforming traditional sealing methods involving house wrap.

Why ZIP System® Sheathing

By simply taping the panel seams with ZIP System Tape, the system effectively seals the building envelope, decreasing unwanted air leakage into and out of the home. ZIP System® panels are structural PS-2 rated panels with permanently integrated protective barriers. They’re engineered to withstand the demands of the job site and provide long-term performance within the building structure. That’s superior performance we ensure through extreme tests.

 



The Benefits of Reduced Air Leakage

Preventing the loss of conditioned air
The United States Department of Energy reports that over 30 – 40 percent of the cost of heating and cooling a home is lost to uncontrolled air leakage. This can hamper the performance of other building systems such as insulation and HVAC. Proper air sealing helps reduce uncomfortable temperature fluctuations and often allows for smaller, more efficient HVAC equipment.

Lower utility bills
Maintaining conditioned air means less energy is needed to recondition the air. Less energy means lower utility bills. And since all building systems must perform well together to optimize the energy efficiency of a home, the savings can add up.

Moisture
Wherever air moves, water vapor can follow. Proper air sealing reduces the risk of water vapor moving into the wall system where prolonged exposure can result in moisture issues such as wood rotting and mold, which can cause expensive structural or health problems.

Indoor air quality
Air barrier systems help keep out pollutants such as suspended particulates, dust, insects, odors and more.

 



Build Tight. Ventilate Right.

The building industry is abuzz right now over how tight is too tight when building a home. Can a tight envelope have a negative impact on moisture management or air quality in the home?

Some believe that a fair amount of 'accidental' air leakage is good for a home as it allows for a building to breathe. Unfortunately, this accidental air is uncontrollable and normally of poor quality because of its origin into the building—crawlspaces, attics, garages, etc.

Well-respected building science organizations such as ABAA (Air Barrier Association of America) and ASHRAE (American Society of Heating Refrigerating and Air-Conditioning Engineers) recommend that homes should be built as tightly as possible but with proper ventilation.

 



Keeping Up To Code

The energy codes are changing faster than ever so adhering to code requirements is critical when building. ZIP System wall sheathing has been designed to meet the growingly stringent building code requirements:

  • Current International Residential Codes (IRC) include the requirement of an air barrier to prevent air leakage through the building envelope (IECC Section 202).
  • Compared to 2009 when 7 air changes per hour (ACH) were acceptable in any climate, in 2012, this number must be decreased to 3 or 5 air changes per hour, depending on the climate zone. A 'blower door test' which measures ACH will also become mandatory to verify code compliance.
  • In order to meet EnergyStar certification on a new home, builders must prove that complete air barrier systems are in place throughout the house.
 



An Airtight Argument for ZIP System Sheathing

Independent testing labs have demonstrated the difference in air leakage between ZIP System wall sheathing and traditional housewrap through standard air barrier assembly testing. The results are clear. ZIP System wall sheathing outperformed traditional housewrap—proving the superiority of a ZIP System air barrier.

 



The Challenge of Protecting R-Value

One of the biggest challenges facing builders today is finding the perfect insulation method and maintaining the R-value of that insulation. Both can help you achieve a higher level of energy efficiency. And this is where ZIP System wall sheathing comes into play.

But what exactly is meant by insulation and R-value?

Insulation is the material used to create a thermal barrier between the interior and and exterior surfaces of a building. The R-value—also known as the thermal resistance value—is the measure of thermal resistance to heat transfer or heat flow. It is a popular way of comparing insulation because the higher the R-value, the greater the resistance to heat flow. In extremely cold environments, for example, a higher R-value is needed to prevent the warm air inside a home from flowing out through the walls into the cold air outside. In turn a high R-value helps sustain conditioned air in the home and thus reduce energy costs to recondition the air.

Remember that heat transfer is normally from high temperature to lower temperature. High temperature air or objects have faster moving molecules, which if coming into contact with colder temperature air or objects will cause them to move faster and heat up. So in the example above, the warm inside air in a home will cool down if it comes in contact with the colder air outside.

 

The Solution is ZIP System Sheathing

The revolutionary science behind ZIP System sheathing, and ZIP System tape, is the solution to this problem. By sealing panel joints and gaps, and thereby reducing air leakage, ZIP System wall sheathing protects the effective R-value of insulation so that builders and homeowners can:

  • Lower the rate of heat flow
  • Use less energy to heat or cool a home
  • Increase overall energy efficiency
  • Save on heating and cooling costs
 

The Result that ZIP System Sheathing Provides

Heating and cooling account for 50% to 70% of the total energy used in the average home. Managing air infiltration, exfiltration, water vapor and R-value will play an important role in the future of home building. Because air leakage is a significant contributor to energy waste, properly sealing the building envelope is one of the most critical steps in constructing an energy-efficient home, and therefore, saving on energy costs.

ZIP System sheathing has a built in air-resistant barrier that does just that, and ZIP System's proprietary tape helps eliminate gaps in the building envelope, reducing air leakage from areas such as wall joints.

To prove this, builders or homeowners can use a HERS Rater (Home Energy Rating System) or a BPI Auditor (Building Performance Institute). Either group offers trained professionals who can conduct a Blower Door Test on the home.

HERS primarily addresses new construction and is the method used to achieve Energy Star. BPI primarily addresses existing homes and weatherization upgrades.

Blower Door testing is typically done as part of a whole home energy audit. A blower door is a diagnostic tool designed to measure the air tightness of buildings, and to help locate air leakage sites. The test can identify the Air Exchange per Hour (ACH) of a home. This can be modeled to help determine how much energy is needed to heat or cool a home. The lower the ACH, the lower the energy bill. ZIP System panels help you ensure a lower ACH or a tighter home.

 

For a homeowner, a tighter home means:

  • Energy savings - Homeowners with ZIP System sheathing save an average of 10.5% on their utility bills.
  • Increased comfort inside the home - Protecting against air leakage and drafts leads to a more comfortable living space where it counts the most.
  • Improved air quality - Air barrier systems such as ZIP System wall sheathing keep families safe by protecting against harmful pollutants.

A Tighter Seal That Protects R-Value

Air leakage lessens the ability of insulation to resist heat fl ow, reducing its effective thermal resistance (R-value). By eliminating gaps in the building envelope for a tighter seal, ZIP System® Sheathing better protects the wall system and prevents air leakage from degrading R-value.