The time has come and the State of Texas has adopted the energy provisions of the 2015 International Residential Code as the minimum energy efficiency standard for all new residential construction. This will take effect on all homes permitted on or after September 1, 2016. As part of the adoption, the State of Texas cannot adopt a newer energy code more often than once every 6 years.
One major difference in the 2015 International Residential Code vs. the current 2009 International Residential Code is the additional of an alternative compliance method- the Energy Rating Index. Each home now has multiple compliance options available: Prescriptive, Prescriptive with UA trade-offs (insulation and sheathing), performance, or an Energy Rating Index. This is very similar to the HERS Rating index, and thus far all municipalities have accepted the RESNET HERS Index as a compliance option. The state adopted a less stringent target Rating Index for climate zones 2 & 3 (Dallas / Fort Worth, Waco, Austin, San Antonio, and Houston markets are included in these climate zones) of 65, and it will stage down over the next 6 years to rating of 59.
Another major achievement in this code is the flexibility in duct testing using the Simulated Performance Alternative or the Energy Rating Index options.
There are other items that will affect the performance of the home and several mandatory items that need to be changed in order to meet the 2015 requirements.
Listed below are some of the more impactful items:
- 75% High Efficacy Lighting
- Blower Door 5 ACH50 (2009 Energy Code 7 ACH50) Houston, Austin, San Antonio
- Blower Door 3 ACH50 (2009 Energy Code 7 ACH50) Dallas / Fort Worth and Above
- Whole House Mechanical Ventilation
- Advanced Framing at Corners & T-Walls
- Higher Insulation R-Values- Trade-offs Available
- Vinyl Windows Standard- Trade-offs Available
There is one major win for us in the building community. We have confirmed with the International Code Council that they do NOT require foam board insulation to be installed in header assemblies unless there is a voided cavity to be filled. For example: 2x member headers with OSB or plywood sandwiched in-between the members is code compliant and does NOT require foam board insulation.
There are many more items to consider, and we will be glad to provide performance analysis to help you determine what the best compliance option for your homes. Please feel free to reach out to me with any questions you may have.