Friday, 27 July 2012

Pursuing Passive House certification

Canada's first certified residential Passive House, located in Ottawa, Ontario.
Designed and built by Chris Straka, Vert Design. This duplex silenced the
naysayers that thought a Passive House could not be built in Canada because
of the severe climate. Chris proved them all wrong with this house and he will
do it again. Chris is the architect designing Casa Tortuga at Turtle Falls.
We've been at the house design stage in this process of building a Passive House here at Turtle Falls for just about a month and a half now. From our initial thought of  building a completely off-the-grid, solar-powered home we have had a chance to research what is possible and available to us. Once we discovered passive solar design we incorporated that into what we wanted for this house. But the most exciting discovery we have made, and will strive to achieve, is Passive House certification.

Passive House is an approach to design and construction that relies on a super efficient airtight envelope, essentially minimizing heat losses to optimize gains from the sun as well as the smallest heat sources like body heat, cooking heat, and hair dryers. With a super efficient envelope, you get to keep all heat in, or out depending on the season. Construction of a Passive House employs meticulous attention to air sealing, reduction in thermal bridging (heat loss through framing lumber), optimizing site orientation (true south exposure), insulation levels (3-7 times more than standard), and installing high performance windows (triple glazed, insulated frame) and HVAC systems. There is also a component of Passive House that focuses on minimizing energy demands with highly efficient appliances and a mindset for conservation...eliminate those phantom loads! When all of this is done, the house will be 80-90% more efficient than a standard-built house and be substantially more comfortable, affordable and healthy.

Passive House can be thought of as the wiser, more experienced cousin of passive solar design, which has been in existence for about 5000 years. Passive solar design employs the use of solar gain through south-facing windows and large thermal mass, such as concrete floors or walls, to store and release heat. What was missing in the passive solar homes from the 1970's and 80's was, most importantly, the improved air sealing, thermal bridge elimination and high performance windows.

Germany's first Passivhaus
The first Passivehaus was built in Darmstadt, Germany in 1990 and the Passivhaus Institut was founded in 1996 in the same city. To date, Germany leads the way in Passive House construction with well over 20,000 buildings and growing every day. If you would like to know more about Passive House, visit the Canadian Passive House Institute website at or the Passive House Institute website of your own home country. There are almost as many websites about Passive House as there are Passive Houses in Germany so any search engine will find you plenty of info for those looking for more.

This is our destination to visit in Australia when we're
no longer wasting our money on heating fuel.
Thanks Lan & Treen for the beautiful photo.
It amazes me that we did not know about this brilliant Passive House way of building before beginning this journey. But then why would we? The building code standard in Canada is what most of us know because all we strive for is a satisfactory amount of energy efficiency for the lowest possible price per square foot. It is quite sad that the standard we aim for in this country is actually very sub-standard. Considering that Canada's home heating costs are one of the highest in the world you would think we would want to do a little better at keeping that heated air inside our homes. Part of the blame for not wanting to do better at this is the decades of low-cost fuels we have experienced. It probably won't take long for Passive House to become more mainstream now with the ever-increasing cost of the fossil fuels we use to heat our homes. It costs only 10% more to build a home to Passive House standards, and for the rest of the home's life it will use 80-90% less energy to heat. The extra cost to build will be recouped in 6-10 years from decreased need for heating and electricity. And a Passive House will last much longer than a standard-built home. Once we fully understood the Passive House concept, we went all in! Why wouldn't we? I'd rather spend the money we'd normally spend on heating our home elsewhere...somewhere like Australia, say...visiting friends also building their own little piece of paradise within a smaller environmental footprint.

An early version of the Casa Tortuga floor plan.
©2012 Chris Straka, Vert Design
Just over a month ago, Ras and I went with architect Chris to meet with Homesol Building Solutions, a premier Canadian company providing accurate and cost-effective residential energy design services. They provide all the modelling and testing services necessary to achieve Passive House certification. Homesol's list of services also includes LEED, Energy Star, Home Energy Audits, R2000 Certification and much more. In building a Passive House it is important to test for a super tight air seal during construction so any leaks can be fixed before the drywall is installed, not after, when fixes would be more difficult and costly. They handle intricacies of the building details necessary to achieve our goal while saving us time and money. Homesol also takes care of all the paperwork necessary for certification. And if all goes well, Casa Tortuga will become Canada's latest certified Passive House, an honour bestowed upon few presently. Fingers crossed...although we will probably not need it. We have a very experienced team with Vert Design and Homesol Building Solutions working on bringing Passive House Casa Tortuga to reality!

The following image is a screen shot of a Twitter conversation I had with Ross from Homesol Building Solutions. July 17th was that wicked hot day and it was sweltering inside Priscilla as well as on the dock. I wanted to know what it was like in Ross's Passive House.

Maybe the building of our little turtle palace, as one friend nicknamed Casa Tortuga, will help get the word out about Passive House construction just a little bit more. Feel free to pass this blog onto others you think may be interested in discovering the benefits of  living in a home that is low maintenance, durable, super energy efficient and sustainable.

Much more to come,


Sandy said...

You gals rock!! And guess what....your cookware is 86% more energy efficient than using the stove and you've been more green than u realize over the last 16 yrs!

C&M said...

You Ladies are too much. You may be building a Passive house but you are not passive girls. Once the house is complete, we can move in your out house. Is it rated passive?

Anonymous said...

Hi Cousin
You and Raz rock!
Good luck with the whole building process.
The more efficient you can be the better