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An Introduction to the Flatrock Passive House

In Newfoundland, Canada, climbing energy costs drive a plan to build a new home to the Passive House standard

Posted on May 31 2017 by David Goodyear

Editor's Note: This is the first in a series of posts by David Goodyear describing the construction of his new home in Flatrock, Newfoundland, the first in the province to be built to the Passive HouseA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. standard. You can find Goodyear's complete blog here. This post was originally published in January 2017.

So, after 8 1/2 years in our home, we have decided to move on. Well, not right away! We have quite a bit of planning ahead of us. With the likely onset of a 233% hike in the cost of electricity from Muskrat Falls (when compared to today's rate of $0.0972/kWh), we decided it was time to take energy consumption seriously — before it's too late to do anything about it.

The land has been acquired, and the planning has started. I am planning on nipping my energy bill in the bud before it becomes a major sinkhole in my pocketbook.

Upon investigating current building standards, I realized that the Canadian building code is below the standards necessary to really make a difference in energy consumption. There are some standards, such as R-2000, which can make a difference to total energy usage. A R-2000 home can use up to 50% less heating energy compared to a code-built home; if built properly. A blower-door testTest used to determine a home’s airtightness: a powerful fan is mounted in an exterior door opening and used to pressurize or depressurize the house. By measuring the force needed to maintain a certain pressure difference, a measure of the home’s airtightness can be determined. Operating the blower door also exaggerates air leakage and permits a weatherization contractor to find and seal those leakage areas. will reveal the truth about that.

There is a better way

Now, imagine living in a home where you have employed five guiding principles during design:

(1) Super-efficient envelope: Superinsulated, thermal-bridge-free walls that are airtight.

(2) Efficient layout of mechanicals: Energy-efficient wiring and efficient plumbing layouts.

(3) Controlled ventilation: Use of a heat-recovery or energy-recovery ventilator(ERV). The part of a balanced ventilation system that captures water vapor and heat from one airstream to condition another. In cold climates, water vapor captured from the outgoing airstream by ERVs can humidify incoming air. In hot-humid climates, ERVs can help maintain (but not reduce) the interior relative humidity as outside air is conditioned by the ERV. to control the amount of ventilation and recapture energy.

(4) Integrating passive elements: Using large south-facing triple-glazed windows to capture solar energy.

(5) Use of renewable energy: This could be anything from PVPhotovoltaics. Generation of electricity directly from sunlight. A photovoltaic (PV) cell has no moving parts; electrons are energized by sunlight and result in current flow. to solar thermal to a wood stove.

If I told you that this home will use between 80% and 90% less heating energy than a code-built home, you would think I was off my rocker. If I told you that my hot water costs are now going to be the largest part of my electrical bill, you would say that's not possible. Well, it is possible. I didn't fall of the rocker. I stood up and started looking, and realized there is a whole lot of science that has gone into creating buildings with energy efficiencies you wouldn't think were possible in a cold climate. Such a crazy standard does exist. It's called Passivhaus and although the origins were in Canada, it was researched and refined in Germany.

To put the power usage for a house like this in perspective, most homes around the size of our house are using up to 30,000 kWh of energy per year. It's an early estimate, but we are expecting that our annual energy usage for the new home to be 8,000 kWh. That's a whopping 75% reduction in energy usage. How is this possible? Science — and a lot of it.

Do you need a Passive House consultant?

A home is more than a floor plan. According to Passive House principles, there are a lot of details to get right beyond a simple floor plan. If you want a high-performance home that has predictable energy usage, it comes at a price. That premium is a small price to pay. The final outcome is a predictable home.

Working with an architect and/or a Passive House consultant is probably the most important part of the project. Without their expertise, you'll still end up with a superinsulated house, which will decrease your energy bill, but other details may be missed. Will overheating be a factor? Do you need extra overhangs to minimize solar gain during the summer? Do your north-facing windows lose more energy in the winter than the solar gains on the south face? These questions can be answered up front, before the home gets built. That's the job of the Passive House consultant.

We wanted to keep our business as local as possible. There are no Passive House consultants in Newfoundland and Labrador, so naturally we looked to Nova Scotia. Nova Scotia has made leaps and strides in implementing Passive House. There already are many Passive House buildings constructed. Nova Scotia's provincial government has even funded Passive House projects for multifamily housing and provided up to $10,000 in incentives for homeowners wishing to build a Passive House.

Forget about the minor insulation upgrades that we received from the Take Charge program in Newfoundland. These guys are going all the way. And I can understand why: Nova Scotia gets most of its power from burning coal. They have a time-of-use system for charging customers based on the time of the day. Their energy costs vary from $.08/kWh to $0.19/kWh. Cutting energy use is a huge mandate on the province's list of "to-dos."

I doubt that we will see anything like this here anytime soon, given the state of Muskrat Falls. Giving people rebates so their power bills are lower just means that we'll be paying less to pay for the cost of the project.

Rounding up our Passive House team

I decided to contact Natalie Leonard, a professional engineer and a Certified Passive House Consultant. Natalie has been involved in over 40 projects to date and has been very successful. One of her architects, Mike Anderson, is the lead project designer. Mike has a degree in physics, which seems like a natural match for performance homes that involve a lot of physics. After several lengthy phone conversations, Natalie's company was an obvious choice. It seemed like a natural match.

I decided early in the game that I would have to complete the builders' course offered by the Passive House Institute U.S. myself since there are no Passive House builders in Newfoundland/Labrador. Natalie was teaching the course at Ryerson University in Toronto in December, so I had the opportunity to complete the course and meet Natalie in person. I can say that it was an amazing course. Natalie did a great job teaching it and her knowledge of the content was obvious.

I am glad that we have Passive Design Solutions working on this project with us. The contract spells out what is expected from me and what I can expect from them. All aspects of the building will be planned, from lighting to plumbing to ventilation, all optimized to minimize energy use. That being said, the first round of schematics, including lot placements, are completed. I'll discuss lot placement and the house schematics next.

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