Yesterday I went to the Georgia Department of Community Affairs (DCA) for a meeting of the State Codes Advisory Committee (SCAC). Wait, wait, don't leave yet! I promise there's good stuff in here.
OK, let's try that again.
Yesterday I saw a bunch of guys sitting around a table make a groundbreaking decision that will alter the lives of home builders, energy raters, and utility customers. Yes, I'm talking about the great work done by the Georgia 2009 International Energy Conservation Code (IECC) Task Force over the past year. The SCAC received the Task Force's report and considered it at their meeting today.
The tension was high in the room. Attendees glanced around nervously, keeping an eye out for last minute subterfuge. Groups of like-minded stakeholders gathered together for protection against enemy stakeholders, expecting at any moment to have to fend off the long-dreaded attacks on their hard-fought victories in the Task Force's report.
Actually, it wasn't like that at all. The room was full, the SCAC members and DCA staff sitting around the large table and interested parties like myself sitting around the edges of the room. Those of us who support the progressive changes I'll describe below did have some concern that debate could erupt during discussion of the report, but it turns out those fears were unfounded.
Jim Vaseff, chair of the 2009 IECC Task Force, presented the results of their work. Morgan Wheeler, chair of the SCAC, asked if there was any discussion, and there was none. The motion to adopt got a second and a unanimous voice vote. Hooray! The new Georgia state energy code passed (download at bottom). There will be a public hearing in September and final approval in November, but everyone seems to think it's a done deal now. The new Georgia energy code goes into effect 1 January 2011.
Now, let's get to the details. I won't go into the full 2009 IECC here, just the most interesting of the Georgia supplements and amendments relating to the residential energy code.
Blower Door Testing Required
I first broke the news of the requirement for all new houses to pass a Blower Door test back in early May. As I stated there, the 2009 IECC provides two paths for compliance with air-sealing requirements: a visual inspection and a pressure test. Georgia decided that the visual inspection was inadequate and went only with the Blower Door test. According to Paul Karrer of the Building Codes Assistance Project (BCAP), "That was an extremely interesting (and as far as I’ve seen, unique) addition to the state’s new energy codes." Task force member Mike Barcik deserves a lot of credit for getting the Blower Door test required.
So, how will this work? Starting on 1 January 2011, all new homes permitted for construction will have to get a Blower Door test for infiltration. The result must be less than 7 air changes per hour at 50 Pascals (ACH50). This level of airtightness is a good starting point. It's not that hard to achieve, so every builder can do it, but I expect to see that number come down in future versions of the Georgia energy code.
Only a certified Duct & Envelope Tightness (DET) verifier will be allowed to do this testing. Anyone certified as a HERS rater, Home Performance with ENERGY STAR contractor, or BPI Building Analyst automatically qualifies as a certified DET verifier. Everyone else will have to pass a certified DET verifier class approved by the Georgia DCA. (Energy Vanguard will offer such a class.)
Duct Leakage Testing Required
The 2009 IECC requires all ducts outside the building envelope (in unconditioned spaces) to be tested for leakage. The Georgia energy code requires that the duct leakage outside the envelope be less than 8 cubic feet per minute per 100 square feet of conditioned floor area if tested after construction, 6 cfm/100 ft2 if tested after rough-in.
Also, as I read the Georgia Supplements & Amendments document, mastic is required. HVAC contractors can use code approved tape, but they still have to put mastic over it.
Other New Requirements
I mentioned in my first article on the new Georgia energy code that power attic ventilators will not be allowed. The actual language doesn't say a builder can't install them; they just can't connect them
to the electric grid. One exception is specifically called out - solar powered attic ventilators. The building science still doesn't support these devices, but we're after progress, not perfection here.
Another biggie is that electric furnaces are no longer allowed as a primary heat source. Sorry, Georgia Power. I know those things generate a lot of revenue for you, but turning heat into electricity and then back into heat is just stupid, except on a small scale, like for the toast I'm about to make. (If anyone knows where I can get a heat pump toaster, please send me the details!)
Finally, builders will have to install high efficiency lights for at least 50% of a home's lighting. Alternatively, they could install occupancy or vacancy sensors or an automated control system.
The new Georgia state energy code is definitely breaking new ground. The 2009 IECC gave us a good start, but Georgia took another step or two forward, and anyone who buys a new home built under this code will benefit.
Download the 36 page pdf file here:
[Originally posted in the Energy Vanguard Blog, 30 July 2010}