subject: Green Building, Vancouver, Bc [print this page] When it comes to building technology in Vancouver, BC, no other color has been as abused as Green. Today there are green buildings, there is green energy, the green movement, green appliances, technologies and even points (LEED). What is green? How does one quantify what green means, define how green is measured, and place a value on the greenness of a particular product, technology or service?
Green is the color of Vancouvers natural world as reflected in our lawns, landscaping and trees. It is the color of health and vitality and has become a catch all for things good for the earth. Specifically, it is used to identify technologies that reduce carbon emissions and preserve our planet for future generations.
When it comes to homes in Vancouver, what makes a building green? Simply put, it is the energy it uses. Energy production in the United States and Canada is a dirty business. It does not matter if you are speaking of gas powered electric plants, coal driven energy, natural gas furnaces, heating oil or propane, even nuclear creates troublesome byproducts. A building therefore, is green if it accomplishes the task of providing housing while using less energy than a comparable home or building.
First, our homes must serve an essential purpose. A home must provide shelter and be structurally sound, it must prevent rain and snow from entry, it must be fire safe and create a healthy and comfortable indoor living environment. This is the bare minimum required of a building. In order to be a green building it must do this while consuming less energy.
Most green building technologies rave about the benefits of efficiency but this overlooks the more significant gains that can be achieved through conservation. Before you can efficiently condition (heat or cool) air in a building, you must first enclose it. The enclosure is more important than all the air handling systems inside it. Without an air tight building envelope you might as well try to condition the air in a nylon tent you cant, no matter how efficient your heat source.
A good enclosure is one that is air tight and has a high resistivity to heat loss. There are three building envelope technologies that achieve the highest level of performance; Structural insulated panels (OSB-Foam-OSB sandwich) known as S.I.P.s, Insulated Concrete Forms (Foam-Concrete-Foam sandwich) known as I.C.F.s and lastly, conventional framing insulated with spray foam insulation. You will notice that each of these building technologies utilizes foam and there is a reason for that. Because foam contains billions of tiny bubbles separated by micro thin plastic walls, it is the very best insulator available. Because it is impervious to air, it acts as an air barrier. Because it is impervious to water, it is a recognized vapor barrier. The air barrier and vapor barrier characteristics of foam are perhaps even more important than its high R-Value in Vancouver. No other material insulates or creates a better envelope than spray foam insulation, and in Vancouver, where moisture is a constant problem, that is critical.
S.I.P.s and I.C.F.s require special construction techniques and change the construction process. Many builders are unfamiliar with these. Because 99% of residential homes in Vancouver still use conventional framing, spray foam insulation is a much more readily available option for homeowners who want the best building envelope available. Building with one of these envelope technologies results in tight building envelopes and energy efficient homes. This is the real green.
