Energy Star Homes

energy star logoIn 1992 Environmental Protection Agency of the United States developed the ENERGY STAR program. This program was designed to encourage energy-efficient practices to reduce greenhouse gas emissions. By identifying and promoting energy-saving products this initiative helps to protect the environment and lowers energy bills at the same time. In Canada, the ENERGY STAR program is administered by Natural Resources Canada since 2001. ENERGY STAR homes are designed and built so that their energy bills are on average 25 to 30% less than similar homes built to minimum requirements of the building code. They improve comfort for the occupants and reduce greenhouse gases.

In 2012 OBC was changed to reflect stricter requirements of energy efficiency and achieve the EnerGuide 80 rating. The ENERGY STAR technical specifications have also been changed to maintain the 25% – 30% over OBC advantage. The ENERGY STAR program is based on the same solid building science as the R-2000 program but it is designed to be easier for larger builders to implement. The main differences are in less administrative burden, the introduction of the prescriptive requirements, and less airtightness of the building envelope. The EnerGuide rating for the houses is similar to that of the appliances. The EnerGuide scale from 0 to 100 was designed to help consumers make wise energy choices by comparison old and new homes on the same scale. These ratings are generated by HOT2000 software based on insulation levels, window performance, mechanical systems, and airtightness of the houses. Prior to OBC 2012, the ENERGY STAR rating was 80 but after the new code was adopted it went up to 83.

There are certain administrative requirements for the builders to build ENERGY STAR homes. After taking a one-day builder’s workshop and signing an agreement with NRCan builders get certified as ENERGY STAR builders. However, they have to engage the services of an independently certified ENERGY STAR evaluator who will work with the builder from the design stage up until labeling of the house. The evaluator will review the builder’s plans and suggest the path to achieve ENERGY STAR compliance. There are currently two paths available for construction of the ENERGY STAR homes: prescriptive and performance. A prescriptive path is a set of certain requirements developed by Natural Resources Canada that must be present in the house. This includes but is not limited to certain levels of insulation in the attic and main walls, use of ENERGY STAR windows for our climate zone, certain efficiency of the mechanical equipment, etc. The role of the evaluator is to ensure compliance of the finished house with these requirements and perform a final Blower Door test that will determine the “pass or fail” mark for the house. If the house’s airtightness is within the prescribed requirements the house will be labeled as an ENERGY STAR home. Performance path requires modeling of the house in HOT2000 software and achievement of the score of 83 on the EnerGuide scale. In addition, all homes must meet electrical savings credits, ventilation requirements and have all the equipment and appliances labeled as ENERGY STAR.