Passive House: Everything you need to know
People are always looking for ways to save on their energy, but there are rarely new methods of doing it. Everybody’s heard about changing out your incandescent light bulbs for LED ones or turning down your thermostat when you’re out to improve energy efficiency. While those are tried and true strategies, they’re not exactly new or exciting. That’s where passive houses come in — not many people have heard about it, but this is a great way to cut down on your energy costs.
If you want to learn more about passive houses in Canada, here’s a full guide on how they work, as well as how they can be effective for reducing both your energy bills and your carbon footprint.
What is a passive house?
Passive homes are houses designed with a focus on minimal energy consumption and great air quality, according to OVO Energy. A passive house will save as much energy as possible. That’s why they are often described as ultra-energy-efficient homes. Be it in summer or winter, a certified passive house will consume the least possible energy, which means low energy bills and a small carbon footprint.
They’re similar to off-grid houses and buildings, which aim to lessen energy consumption by disconnecting from public utilities and create their own energy. At this point, you might be wondering what exactly qualifies passive houses for passive house certification. The main criteria that passive homes need to fulfill are as follows, according to Passive House Canada:
- Space Heat Demand max. 15 kWh/m2a OR Heating load max. 10 W/m2
- Pressurization Test Result @ 50 Pa max. 0.6 ACH (both overpressure and under-pressure)
- Total Primary Energy Demand max. 120 kWh/m2a
Those criteria probably don’t make much sense out of context, so we will explain them here for you. Space heating demand refers to the amount of active heating input required to heat a building usually expressed in kWh/m2/yr, says Passive House Plus.
On a rough note, heating load refers to the amount of heat energy that would need to be added to a space to keep the temperature in a viable range, according to BASIX. By acceptable range, they mean not having the temperature above 25 degrees Celsius for more than 10% of the given hours for a year, according to the Passive House Institute.
The pressurization test result is the result of an airtightness test. An article by Passipedia explains the airtightness test as one that measures how much total leakage occurs through a building envelope. Basically, a building envelope is the physical separator between the outside and inside environments enclosing a structure.
Finally, the primary energy demand refers to the total amount of energy used for domestic applications.
But there are even more common principles and features of passive houses, including heavy insulation, high-efficiency windows and efficient central ventilation, as stated by HowStuffWorks.
The Passive House Institute states having a ventilation unit in place helps fresh air to circulate and helps humidity and heat recovery. Also, heavy insulation helps reduce heat loss and gains, keeping the internal temperature of your home more consistent and comfortable.
Passive home heating and cooling also depends on home orientation. South-facing windows in the Northern Hemisphere can take advantage of the heat the sun provides in the winter while still easily being shaded by overhangs in the summer, a blog post by the International Passive House Association suggests.
Something interesting to note, however, is that there isn’t the ideal window for a passive house. Of course, there are some principles, but the industry hasn’t yet started to produce passive house-focused products. According to Neuffer, high-efficiency windows for passive houses are usually airtight, triple glazed and the gaps in the panes are filled with gases such as argon or krypton.
Windows for passive houses in Canada are available from several different sources — sites such as Passive Green list several dealers that provide windows suitable for passive houses.
How can passive houses cut down my energy costs?
Now that you know what the passive house standards are, perhaps you’d like to look at some examples of passive houses in Canada or even passive buildings in Canada. Maybe you’re just skeptical of whether they actually exist or not. Regardless, these passive house examples may help you decide whether looking into building or moving into a passive home is right for you and your lifestyle. They’ll also help you consider some of the benefits of living in a passive house.
One particularly amazing example is the passive house tower designed by Henson Developments to be built in Vancouver, British Columbia. Arch Daily describes this passive house tower as 60 stories high and a step away from the stereotypical image that a passive house projects, since this passive house design is atypical. If designing a passive home sounded like a little too much work for you, passive buildings like this one would probably be a dream come true for you. You wouldn’t have to put a lot of time and effort into designing a passive house and the cost would probably be a little less than if you were to live in a single stand-alone passive home on your own.
Another example of a passive house is the Windsor Park Net Zero House in Edmonton. Net-zero houses are houses that produce as much energy as they consume, according to the Canadian Home Builders’ Association. This passive home showcases the fact that a passive home can be both practical and aesthetically pleasing.
In addition to this, the Windsor Park Net Zero house shows that passive homes don’t need to be isolated. EcoHome states that this passive home is located conveniently near a subway station and near an urban core. Best of all, it also shows that passive homes aren’t necessarily unaffordable to live in, as part of this home is rented as a suite for student housing, according to the website.
At this point, you might be thinking that while a passive home sounds nice, it doesn’t sound like something that’s achievable for a typical family. A Calgary home inhabited by a family of four that was recently certified as the first passive house in Alberta would certainly surprise you then. This passive home is particularly amazing, especially given how cold winters can get in Alberta.
In addition, this Calgary home gives a little insight into the building process of passive house construction. While it is possible for a family to plan out and build a passive house, it’s a long process. It took this family about four years to be able to move into their passive home beginning from when they purchased the lot for their home, according to a CBC article.
The Calgary example of a passive home may have gotten you thinking about how to build a passive house yourself. Building a passive house seems like a daunting task — where do you even start? First, you may want to consider whether you want to build a passive house from scratch or if you’d like to refurbish an already existing building with passive house certified components.
Some advantages of simply refurbishing an existing building or home to fit passive house standards could include less design work and not having to move from your existing home. However, if you choose to refurbish, you may have less control over the design of your home if everything is to meet passive house standards. Sources like the Passive House Institute have several resources and publications on refurbishing to passive house standards.
For example, they have guides on retrofitting windows or affordable ventilation for retrofitting. If you want to build a passive home from the ground up, attending a course for passive house and design can help you get started. Passive House Canada provides several such courses available across Canada. If you’d like a more hands-off approach, hiring a passive house designer is also an option.
The passive house costs
Another important thing to consider if you want to build a passive home are the costs associated with it. Passive house costs are composed of several things such as hiring a designer, buying insulation materials or purchasing passive home compliant materials.
A misconception often associated with passive homes is that they’re more expensive than conventional homes. According to the Zero Energy Project, the cost for designing a passive house could cost between $175 and $200 per square foot. An article from ReMax shows that this cost isn’t too far off from regular detached homes — for example, a detached home in Toronto would cost between $110-$210 per square foot.
These costs, however, can change considerably depending on your location, the size of the home you’re designing and your energy efficiency goals. It’s also important to have in mind that, even though building a passive house can be costly, you will get a great deal of your money back in energy savings in the long run.
The pros and cons of passive houses
To sum things up, let’s talk about the overall pros and cons of passive homes. Passive homes have several advantages, including lower energy bills, better air quality inside, reducing your carbon footprint and low maintenance costs.
However, there are cons too. Passive home disadvantages include that the upfront cost of building a passive home can be quite high, according to Conserve Energy Future.
In addition to this, passive homes may or may not retain their value, depending on the neighborhood that they’re built in. An article by NewYork Engineers claims that in particularly harsh winters, a back-up heating system might be necessary for passive homes. That could be a hassle, as well as expensive to run.
While passive homes have several advantages and are a considerably novel way of saving energy, they do come with a few disadvantages as well. Hopefully, this post will have given you insight as to whether a passive house is right for you based on the criteria needed to qualify a house as a passive house, current examples of passive homes, as well as the advantages and disadvantages of passive homes.
To learn more about energy efficiency and how to save energy at your home or business in Canada, go to EnergyRates.ca. The website provides you with in-depth resources on everything energy savings, as well as a cost comparison tool for you to compare energy rates in your area.
