I remember viewing a home on the ecosolar home tour a few years back that had just been expanded to 3000 ft.² plus a full basement. I walked away from that home shaking my head - can we really call 1000 ft.² of living space per person green?

The Mill Creek NetZero Home (MCNZH) is now fully framed, and it’s looking pretty big on the streetscape. We built a pretty big house, and I wanted to document some of the considerations that went into the decisions we made.

The official square footage of the MCNZH is 2280 ft.² With a full basement, that’s 3267 ft.² of living space. For four people, that’s definitely more space than we need. I am not a believer in the “techno-fix”. Technology will not save us from having to make changes to our lifestyle. We will have to considerably scale it down to start fixing the problems that we’ve caused.

So, while I acknowledge that our new home will be luxurious by world standards, here are some of the mitigating factors for its size:

• It’s actually only 2064 ft.² of living space by conventional measurements. Because the walls are 16″ thick, we lose 10″ of space per wall versus a regular 2×6 wall.
• Once it becomes legal to have suites in our neighbourhood, which should be in December 2008, two thirds of our basement will become a suite. This will increase the population density of the house by effectively making it two houses in one.
• The home is being built to “flex” to our needs. Once the children leave, we will be able to quite easily turn the upstairs into a separate suite. This way, there will always be four or more people living on the main and second floors.
• This house is a hedge against future uncertainty. I believe that we are going to have to move back to the multi-generational household at some point. Having more room will be better when the tough times hit.
• After much deliberation, we decided to add a loft - essentially a half-story - to the home. What put me over the edge in favour of the space was the heat-loss computer modelling that I did. It showed that the extra 306 ft.² from the loft would only cost us 400 kWh per year in heating energy. The flexibility that the extra space gives us was worth it.

I’m sure that we could have cut back on more space somewhere, but when you’re spending your life savings on something it’s tough. The incremental cost to add more square feet is so low once you’re building already…I guess that’s how everyone thinks, and that’s how our houses got so big.

We are very excited to move into the MCNZH. It’s going to be more space than we need, but we’ll try to use it fully and wisely.

(cross-posted at greenedmonton.ca)