Our web partners at Ecohome.net have recently taken passive heating and cooling to a new level, and released a program called Net Zero Heat [NZH]. It is a rating system unlike most others, as it is also a design service that promotes an entirely new philosophy in home design.
↦ SUBSCRIBE TO THE DIGITAL OR PRINT ISSUE OF ECOHOUSE CANADA FOR THE FULL VERSION OF THIS ARTICLE.
Rating system and design service practical way to save energy
According to Ecohome’s engineer Denis Boyer, in most parts of Canada with very specific building dimensions, orientation and window design, the sun can provide sufficient heat to keep a house around normal room temperature with no auxiliary heat source, even in the dead of winter.
Using regionally-specific climate data [average temperatures, sun hours and cloud coverage] and analysing it through Passive House Planning Package software [PHPP], Ecohome can determine the thermal performance and design parameters required to achieve 0 kWh of heat demand in a given location.
While they have several homes in the design phase, there is only one NZH house standing so far, and with that Ecohome already has a 2013 Home of the Year award under their belt from US-based Green Builder Media. The Kenogami House [featured on page 38] in Northern Quebec has an NZH rating of 14.6 kWh and holds the the highest LEED score ever achieved in Canada [106].
Despite the name and the concept, the Ecohome design team is quick to point out that aiming for zero heat demand is not always recommended for the good of the planet or your wallet. There may come a point where you are best to stop insulating and start heating, as in some cases you man not recoup the financial investment nor the energy used to produce added insulation.
“This is not a rigid system intended to chase a goal at any cost” says engineer Denis Boyer, “The shape, wall assembly, orientation and location of your home may mean your lowest impact and best return on investment happens by limiting insulation at a given point, and adding a bit of heat. The intent of this program is to help you find that point.”
The Net Zero Heat program pays homage to the Saskatchewan Conservation House built in 1977, and recognizes any home that can at least match its performance of 75 kWh per square meter per year of heat requirement.
With one house built in a very harsh climate that stopped short of zero heat demand, Ecohome is looking for the first person to build a cold climate home with 0 kWh of heat demand. As they point out on their website, the ability to do so is a mathematical certainty, it just hasn’t been done yet. This is a high profile prize waiting to be claimed by the builder that wants it the most. Learn more at Netzeroheat.com.
