A local family is in the process of building a net-zero house on the westside of Lethbridge. Brian Sexton agreed to talk about the project and answer some of our questions about the construction of their net-zero house.
Tell me a little bit about yourself?
My wife, Katrina, and I have always had an interest in energy efficiency, whether it was with our vehicles or in our home. We are both engineers by training and have been exposed to various energy efficiency projects through our work. Today we both work in environmental fields which fits well with our personal values. Outside of work time, we focus on our two young boys; Connor and Alex and enjoy outside pursuits, especially running. Spare time is rare these days but when there is time, Katrina enjoys quilting and I enjoy making biofuel for one of our vehicles.
What is a net-zero home?
A net-zero home is a home that, over the course of a year, produces the same amount of energy as it uses. This is achieved by incorporating four important factors into the design of the house:
This includes high levels of insulation and air sealing in the walls and attic. Energy conserving windows are also important.
This involves capturing as much energy as possible that is known to be leaving the home. For example, a heat recovery ventilator is used to capture some of the heat from exhaust air leaving the home.
This involves choosing high efficiency lights and appliances.
In a net zero home this typically means using solar panels to produce electricity for the home. When the solar panels are producing more energy than the home needs, the surplus is supplied to the electricity grid. Otherwise, the home draws electricity from the grid like any other home.
What made you want to build a net-zero home?
The first home we ever owned was very energy efficient but, being our first time paying energy bills, we didn’t realize just how efficient the house was. Our friends would tell us how high their bills were and we just assumed they were leaving the heat and lights on all day. Then we moved to a newer, similar sized house and our energy bills more than doubled. That’s when we realized just how efficient our first house was, and how inefficient traditionally built houses can be. We tried a few things to reduce our energy costs but to little or no avail. The cost of upgrading the home to an energy standard that we were used to was just too costly. So we decided to build new. After doing a bit of research, we discovered there were a number of home builders in Edmonton building net-zero homes.
What was the biggest challenge you encountered?
To date, there really hasn’t been any major challenge. There have been a number of small challenges along the way but I believe these are no different than the challenges encountered with building a traditional house. The net-zero home we are building uses all the same construction materials as a traditional home, things are just assembled a little differently and special attention is paid to certain details.
What was the most important thing you learned during the project?
We learned that “what’s behind the wall” is extremely important in net-zero home construction. Attention to detail, especially insulation and air sealing, is critical to the success of a net-zero home. In other words, the things that get covered up. The average home buyer tends to be more concerned with what they can see (flooring, paint, and countertops) than they are with the things they can’t see (insulation, air sealing, and energy loss) so there needs to be a shift in thinking here.
What words of advice would you have for others who are considering a net-zero building?
I think the most important thing is to find a designer or a builder who has lots of experience in net-zero housing. We were lucky enough to work with Peter Amerongen of Habitat Studio in Edmonton. Peter has a wealth of knowledge and experience in the area of net-zero housing.
What do you see as the future potential for similar projects in Lethbridge?