Sustainability is a ridiculously over-used word. Its original intention and definition (by the UN Brundtland Commission in 1987) was admirable and true – unfortunately, it has been bastardized beyond recognition to now mean more about maintaining the status quo in order to sell products than, in fact, doing anything that is truly great for creating longevity for us to live happy and healthy lives in perpetuity as a species. As I once heard Cradle to Cradle architect and author William McDonough say in a lecture a few years ago at the University of Calgary, “If you go from smoking two packs a day to one pack a day, you’re still smoking one pack a day and not repairing your lungs.”
Buildings are directly and indirectly responsible for a significant percentage of greenhouse gas emissions. This is a result of everything from the mining/harvesting, production and shipping of materials to heating/cooling, lighting and general operations. And while steps have been taken in the development and implementation of technology in houses to improve the efficiency of this technology (e.g. HVAC), this improvement in efficiency still is like smoking a pack a day, especially in Alberta where the vast majority of power and heating is coming from carbon based non-renewables like coal and natural gas.
The key to changing our reliance on the technology (albeit much improved) so that we aren’t smoking comes down to actually designing a home so that it doesn’t rely on the additive necessity of technology.
The problem with your typical suburban builder home is that it wasn’t designed for anywhere in particular. It was conceived on a drafting board or on a computer based on a typical lot size for an area but there was no consideration for what direction it will face or what latitude it will be at on the globe or quite frankly, even the climate zone that it will exist in. It is the reason why a new suburban home in Edmonton, Calgary, the Greater Toronto Area and the outskirts of Phoenix pretty much look the same. No one took the time or had the inclination to think about anything more than lowest common denominator - Do you want the base vinyl siding or would you like to upgrade the garage corners to cultured stone?
What this means is that in order to create a comfortable indoor environment we have to rely on technology of heating and air conditioning systems.
Natural air conditioning - An example of how house design helps you to not smoke is a simple one that comes down to the size, placement and orientation of windows to use the simple, natural physical properties of warm and cool air. In complex engineering-speak, it is calledfluid dynamics, in laymen’s terms, it is called hot air rises.
By placing an operable window (one that you can open) at a high level on a wall in a second storey hallway, at the top of a stair or double volume space, the warm air in your house can escape as it rises. In order for this to be effective, however, it is necessary to also have operable windows at a lower and opposite location from the high window in order to create a draft. But to really punch up the natural effects, it is important to locate the lower windows on the north side of your house. This ensures that the air coming in has been in shadow and is much cooler.
So if both sets of windows (high and low) are open – the hot air rises and escapes out of the high window while the cool air comes in to take its place. Plus, because the air is moving and a draft is created, the air feels cooler. This is wicked simple. But in order to do it, the plan of the house must allow for this with the room layout, stair locations, and ceiling heights.
Our Westmount House uses this principle and, while still under construction, is already performing very well. The building envelope has already been buttoned-up and we are without the use of our HVAC system yet. In the past couple of weeks we have been experiencing +30C temperatures in Edmonton. I went into the house during this stretch of heat and the indoor temperatures were 10C cooler.
The air conditioning in this house doesn’t require any smoke.