Texas Home Beating Utility Projections by 140%!
The latest Omni Block Home Energy Rating System (HERS) evaluation was recently completed in Alvarado, Texas. The 2512 sq. ft. single-story total electric house, owned by Mr. and Mrs. Pete Muzika, scored a 58 (see floor plan below). This basically means that the house should perform 42% better than the prevailing energy code. The certificate can be seen below. The HERS evaluation includes a blower door test and a duct blaster test as well as the make and model of all appliances and the HVAC system. The third-party testing company, TexEnergy Solutions, used an R-19.6 for the Omni Block walls. When questioned about why they used this lower R-Value the lead project coordinator responded, “That 19.6 was the highest R-Value that this region can input. Any higher R-Value inputed would not change the overall result.”
Notice that TexEnergy projected the energy consumption to completely run this house at $2,602 annually or approximately $214 a month on average. The owners have now lived in the home for over 11 months, keeping their thermostat set at 72° in the summer and 74° in the winter. The actual average monthly energy cost has been $89!
Statement of fact: This house, built with Omni Block is beating the utility projection by 140%!
The only variable is Omni Block. The reason that they are so far off on their estimate is that current software (REM/Rate) that is used to input the data does not adequately allow for Omni Block’s thermal mass affect on the ambient indoor temperatures.
Tighter is Better
“The 2012 IECC code mandates a maximum Air Changes per Hour (ACH) of 5.0. Many new homes struggle to make that target. To calculate the ACH of this Omni Block home, multiply the blower door test score of 1,380 CFM times 60 minutes per hour and divide by 44,312 (the cubic footage of the house). The result is 1.88 Air Changes per Hour, which is exceptionally tight. This is one of the tightest buildings that we have tested”, according to Bill Syfan, LEED AP HOMES, HERS Rater and NGBS Verifier.