To date, the No. 1 topic of questions and comments about our building project has been our "green" commitment. We claim to be constructing an "eco-modern" home, but are we really being eco-friendly, or are we simply "green-washing"?
I wondered whether I should write about the topic at all for fear of stirring up further accusations and debate. Discussion is healthy, however, and I welcome the dialogue - if not for us, then for those who are considering a similar project.
When we began, our goal wasn't to build a green home. We simply wanted a larger dwelling, and while this remains true, our priorities have definitely changed along the way.
We came to realize that perhaps we should be building a "smarter" home, not just a bigger one. And so began a process of determining what it actually means to be "green."
I asked our architect, Cathy Garrido of Altius Architecture, what it means to build sustainably.
"This is a fairly complicated question" she replied, "and a lot depends upon your definition of sustainability."
The fact is, we wanted to be as green as we could afford to be, something that has proved easier said than done.
Ms. Garrido pointed out, however, that budget constraints usually win out over sustainability.
"We do our best to convince our clients to make a building as energy-efficient as possible and weigh the long-term operating costs against the upfront costs of the more expensive system," she said.
To achieve our goal of building smarter, we decided to invest in design, the heating and ventilation systems, and the building envelope. Of course, this meant we needed to forego a number of other niceties, such as a custom kitchen and high-end finishes.
Relatively speaking, though, these are things that can be changed at a later date for a minimal cost - that is, I expect it will be cheaper to replace an Ikea kitchen than increase the amount of insulation in the walls.
We recognized that the design of the home was critical to achieving our sustainability goals, and working with an eco-minded architect has enabled us to incorporate a number of green solutions.
"The first thing we look at are the opportunities to incorporate passive solar principles into the design," Ms. Garrido explains. "We also try to make sure every room has cross ventilation, and we try to vent the second floor through some clerestory windows or skylights whenever possible."
We designed a large opening in the middle of the house that extends to a clerestory two storeys above. Through a series of both fixed and operable windows, the clerestory will provide natural light and thermal venting. The idea is that day lighting will enable us to reduce our dependence on light fixtures, while the thermal venting will allow us to reduce our use of air conditioning. I expect, however, that we will still require air conditioning to some degree, so we've decided to invest in an ultra-high-efficiency furnace and heat pump system. (We haven't selected a specific brand yet.)
A furnace and heat pump combination is typically referred to as a "dual-fuel" system because it uses both electricity and natural gas. A heat pump is essentially an air conditioner that can both cool and warm a space, although it's not actually cooling the air but moving heat from one place to another. In the summer months, it extracts heat from the house and exhausts it outside. The process is reversed in the cooler months, with the furnace being used on only the coldest days.
Of course, we'd rather not rely on heating or air conditioning systems unless we have to, so building an airtight and well-insulated building envelope is critical. Our foundation was built with insulated concrete forms, which provide insulation on both the outside and inside of the walls.
