9 Steps to A Greener Code
Recent spikes in energy costs have increased the attention on regulatory measures that limit energy waste. Those same energy price increases have also gained the attention of President Obama, who made energy efficiency central to his stimulus package, specifying the need to improve energy efficiency in 2 million homes.
STEP 1: AIR SEALING (Section N1102.4.2)
The code: Building envelope tightness shall be less than or equal to 7 ACH (air changes per hour) when tested at a pressure of 50 Pascals. Testing shall occur any time after rough in and after installation of penetrations of the building envelope, including penetrations for utilities, plumbing, electrical, ventilation, and combustion appliances.
What it means to you
A blower-door test, which measures the airtightness of buildings, will be required for all newly constructed homes, or other significant criteria must be demonstrated.
This requirement does not specify who must observe the test—local inspector or third-party evaluator. So it is likely that a variety of testing conditions will arise across jurisdictional boundaries. You may need to hire an independent third-party testing agency for a test and report that would satisfy the energy inspection. The implication is that leaks that are found must be sealed.
Proving that the house is tight may have associated costs (third party verification or the purchase of testing equipment), most of that will be in attention to detail during construction and sealing the leaks as you build.
For more information on blower-door testing, see “Blower Door Basics.”
N1102.4.3 New wood-burning fireplaces must have gasketed doors and outdoor combustion air.
N1103.2.2 Ducts, air handlers, filter boxes, and building cavities used as ducts shall be sealed. Duct tightness shall be verified through testing during rough-in or post construction.
- N1102.4.1 Attic access openings and rim joists must be air sealed.
The 2009 building codes reflect practices that not only increase energy efficiency—air-sealing measures and increased insulation, for example—but also address sustainable building practices, such as moisture control.
Other segments of this series: