Call Us: 214 929 7317

For Questions, Pricing, and Scheduling

DeCoding the 2015 IECC: Build it Tight, or Else!

DeCoding the 2015 IECC:  Build it Tight, or Else!

MANDATORY Air Leakage Testing

The 2015 IECC requires that each home or multifamily dwelling unit shall be tested and verified for air leakage using a blower door test.

The leakage rate, reported as Air Changes/Hour (ACH) measured @ 50 Pascals pressure, shall not exceed:

  • ♦  Climate Zones 1 & 2:   5 ACH
  • ♦  Climate Zones 3 to 8:   3 ACH


  • ♦  Testing must be done by the building official, or an approved third-party.
  • ♦  A written report of test results for the home, signed by the testing party, shall be provided to the code official.


Texas Climate Zones

Currently, Texas occupies 3 climate zones.

Climate Zone 2, shaded orange. Southern Texas. Major Cities: Houston, San Antonio, Austin and Waco.

Climate Zone 3, shaded yellow. Northeast to far west Texas Major Cities: DFW, Midland, Lubbock and El Paso.

Climate Zone 4, in green. Most of the Texas panhandle. Major City: Amarillo.

The Bottom Line:

The 2015 air leakage requirement is a much higher bar to meet, ESPECIALLY in climate zones 3 & 4!

Current polyseal standards are probably not enough!

For fiberglass or cellulose insulated homes, an AGGRESSIVE regimen of sealing of all holes, cracks, and gaps MUST be put into practice! Reaching 3 ACH will require high attention to detail.

Installed correctly, most spray foam insulated homes may meet 5 ACH for zone 2 compliance, but additional sealing will most likely be required to meet the requirement for zones 3 & 4.

Leave a Reply

Your email address will not be published. Required fields are marked *



7 + 9 =