April 9, 2010
City Council Adopts New Energy Code Amendments; Action Moves Austin Closer to “Zero-Energy” Homes
Energy code amendments approved by the Austin City Council this week will increase the energy-efficiency of each newly constructed home starting this summer by 1,650 kilowatt-hours of electricity a year saving $165 annually (based on a 2,300 square foot home). Combined with energy code amendments adopted three years ago, the efficiency of new homes will increase by 31% since 2007 and save each homeowner 3,630 kWh of electricity and $363 annually.
The series of amendments move Austin closer to the goal of the Austin Climate Protection Plan to make new homes built in 2015 65% percent more efficient than those constructed in 2007. The increased efficiency of the new homes due to the code amendments also will make them Zero-Energy Capable in 2015. Zero-Energy Capable is defined as being so energy efficient that it is cost effective to install enough on-site renewable energy collectors to make the homes truly net-zero energy homes.
Key amendments include requiring a duct blaster and blower door test of each new home to check for duct leakage and leakage from within the structure of the home. Other amendments include increasing the high-efficiency lighting in the home from 25% to 90%, which can be achieved by installing Energy Star rated compact fluorescent bulbs, light emitting diode (LED) technologies, indirect lighting and other high-efficiency lighting that replaces incandescent bulbs.
Also, the insulation value of walls was increased from R-13 to R-15 and the thermal efficiency of windows was improved to reduce heat that windows allow into the house. Hot water pipes also will be insulated with higher energy-efficiency standards than in past codes.
This second series of code amendments also increases the efficiency of new commercial buildings by between 13% and 17% over the current code. New significant commercial amendments include requiring timers for electric water heaters in multifamily properties, heating and air conditioning shut off switches when overhead doors such as bay doors are open, and commissioning of heating and air conditioning systems. Commissioning is the process of verifying that systems are installed as designed and that they function according to design and manufacturer’s specifications.