The construction world is a flutter with talk of energy efficiency. Substantial savings and a positive environmental impact make an energy efficient home a must for home owners. The Canadian government has been proactive about creating legislation to reflect this shift in the building zeitgeist and bolster their own efforts to create more energy efficient neighbourhoods. In a move to expedite this process, governments across the country are adopting the Energuide Rating System to demystify and standardize energy efficiency.
The Energuide energy efficiency rating will help home owners and buyers to get an accurate picture of just how efficient their homes are. The Natural Resources Canada site offers this definition; “An EnerGuide rating shows a standard measure of your home’s energy performance. It shows you (and future buyers) exactly how energy efficient your home is.”
The ratings are given on a scale from 0 to 100. For example, a net zero energy home (a home that produces as much energy as it consumes) will have a rating of 100, while homes built in the 1900s typically have ratings of 45 to 50. Modern homes ideally aim for a rating of 80 (E80).
In a method called the prescriptive approach, a construction company will mix green building methods and materials in a recipe that should result in a home with the ideal energy guide rating of E80. However, the proof is in the pudding as the skill with which the home is constructed determines its efficiency as much as the materials used. The lack of post-construction testing, however, means that homeowners cannot be sure that their home is built to exacting E80 standards.
Whether your home actually meets its E80 construction goals depends largely on the quality of your construction crew. Even if energy efficient construction materials are utilized, air leakage may be what scuttles your E80 hopes. Implementing post-construction leak tests will show how your new energy efficient home really shapes up.
Informed consumers are a plague upon those house builders who cut corners to save costs and construction time, but many construction companies embrace post-construction testing. They see it as a way to show the quality of their workmanship and allay the fears of those consumers who lack the tech-savvy to confidently navigate the relatively murky waters of green construction.
Homes rated with the Energuide Canada system reveal the limitations of traditional construction methods. Although it is possible to create an E80 timber frame home, this is already stretching the efficiency limits of this construction method. In addition, constructing a leak-proof stud frame building requires a very high level of workmanship and more construction time than many in the industry are willing to invest. Where does this leave the prospective green home owner? Well, they are running to the welcoming (and cosy) arms of non-traditional green construction methods such as ICFs (insulated concrete forms).
It takes some skill to build leaky ICF buildings, and the homeowner can easily inspect the joins between wall panels to see if they are sufficiently sealed. Construction time is significantly reduced and insulation is exponentially increased. ICFs offer massive savings on utilities and added protection from the elements. Longevity and strength makes these puppies a far more reliable option for the energy conscious home owner. What about after construction testing? Bring it on!