Origninal article by: Fox Blocks.

Fox Blocks, an Insulated Concrete Forms (ICF) manufacturer, in partnership with GreenBuilt Solutions, a sustainable design facility in Orlando, FL, has managed to build a Net Zero home that has an outstanding HERS Index Score of -22.



The Home Energy Rating System (HERS) Index is the industry-wide standard energy-efficiency measurement of homes. It is also used to determine a home’s energy performance. The lower the HERS Index Score on a home, the more energy-efficient it is. The national average HERS rating posted by RESNET is 58.

“Turning Leaf Construction’s Parade Home in Winter Park is an extremely high performing home achieving a HERS rating of -22,” says Nate Ritter, Director of Sustainability for GreenBuilt Solutions. “It is beyond Net-Zero. One of the most important features in high-performance homes is starting with a well-insulated air-tight envelope like ICF’s. [Using Fox Blocks], ICFs helps provide stable indoor air temperatures, significantly reducing cooling and heating loads and cost.



“When building a home, one only has one chance to get the envelope right. It makes sense to use the most efficient wall system available like ICFs. Homeowners can add PV to reduce their energy bills; with [Fox Blocks] ICFs they can add much less and still achieve Net-Zero.”