- Area of conditioned space 2904
- Btu/ sf/ hdd .51
- Peak heat loss design 11.6 kbtu/h
- Shell area: 5677
- ACH 50 4.23
- Total cfm of blower door 400cfm
- Date of blower door test 4/8/11
- Test performed by Arn McIntyre
- Electrical kwh per year 28.6mmbtu/yr
- Fossil btu per year 20.2mmbtu/yr
- Renewable Elec produced per year 33.5mmbtu/yr
- HERS index -1
"All of man's works intrude upon nature - It is man's obligation to intrude harmoniously."
Alden B. Dow, c. 1958
Tuesday, May 17, 2011
Friday, May 13, 2011
What is a HERS, or Home Energy Rating System score? Well it is basically a rating of how energy efficient a home is based on a number of things, including a blower door test, the HVAC system, energy usage, and so on. The HERS rating is what is used to qualify a home for the Energy Star Rating. The rating is based off of a standard new home built to code that was rated originally tested and used as the test case with the score of 100. A typical older home has a HERS index of 125-150. Most homes that qualify for Energy Star homes must have a HERS rating of 85. That means that those homes are 15% more energy efficient than the test house. This is really good and a step in the right direction. Most of our homes have been scoring in the 50's, which is where we would expect the to fall. That HERS score would qualifies our homes as 5 star+ in the Energy Star rating system. The "River Escape Project" came in at 12 (lower the better) making it 88% more efficient than a new home built to code.
- Certified: Up to 30%.
- Silver: Approximately 30%.
- Gold: Approximately 48%.
- Platinum: 50-60%.
As many know, I am a firm believer in Kaizen ( A Japanese philosophy), or continuous improvement. I am continually studying the building science of homes to make improvements to them so they are as energy efficient as possible within their budgets. So even though a HERS rating of 12 is the best we have achieved so far our goal are to continually improve upon that score with the ultimate goal of a HERS score of 0 or a negative score.