It’s 2012, and the biggest changes proposed for the single-family and low-rise residential construction industry are under discussion and open for commentary at the International Code Council (ICC). The 2012 International Energy Conservation Code (IECC) improves many key measures of the 2009 IECC, such as mandated whole house pressure testing with strict leakage allowances, increased insulation and decreased U-value requirements, hot water pipe insulation and limited hot water pipe lengths, and one change that will affect multifamily builders--the code will penalize electric resistance heating in the performance compliance path.

“Getting away from electric furnaces will add significant costs in gas piping and venting for our affordable apartments,” says Michael Blend, a Montana developer of affordable housing. Electric furnaces cost less to install because they require only one energy input, electricity, and no venting. In multifamily construction, all-electric apartments are popular because they not only cost less to install, but make it easier to meter utilities at the unit level, with a single electric meter required rather than both electric and gas meters.

While it’s true that electrical heating loses very little energy at the point of use when compared with sources that require a chemical reaction, such as oil and gas, this equation only works if you do not include the power plant supplying the electricity. A typical fossil-fuel power plant may deliver only four units of electrical energy for every 10 consumed, turning a 100% efficient electric furnace into, literally, a gas-guzzling SUV of a heater that burns more fuel than an inefficient oil or gas furnace.

Other cost impacts that some view negatively include higher insulation values in climate zones that have not traditionally required it, such as R-45 insulation in the Mid-Atlantic, and the requirement for insulation over exterior sheathing, complicating opening sizes. But the codes remain under consideration until adopted, and you have time to comment by logging on to the Federal eRule-Making portal at

The major changes to the 2012 IECC compared with the 2009 IECC that affect energy efficiency include:

1. Building thermal envelope improvements

a. Increases in prescriptive insulation levels of walls, roofs, and floors

b. Decrease (improvement) in U-factor allowances for fenestration

c. Decrease (improvement) in allowable solar heat gain co-efficient fenestration in warm climates

d. Infiltration control: mandated whole-house pressure test with strict allowance for leakage rates

e. Wall insulation when structural sheathing is used

f. Ventilation fan efficiency

g. Lighting: Increased fraction of lamps required to be high-efficacy

h. Air distribution systems: leakage control requirements

i. Hot water pipe insulation and length requirements

j. Skylight definition change

k. Penalizing electric resistance heating in the performance compliance path

l. Fireplace air leakage control

m. Insulating covers for in-ground hot tubs and spas

n. Baffles for attic insulation

Click here to see the draft proposal and a fully detailed discussion of changes to the IECC.