HOW TO BUILD GREEN A Cost-effective Guide to Contructing a Sustainable Building
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This hierarchical structure allows you to focus on areas that are going to offer you the most substantial energy savings and sustainable future. By following our simple methodology you can ensure your resources are allocated in the most efficient and cost-effective manner.
Energy Efficiency Sustainable Materials
S A V I
Building Envelope Design
N G S
DESIGN DESIGN ENVIRONMENTALLY • Plan your home with designer or architect who is experienced in green design. • For greatest energy efficiency, a house should have a basic, compact shape, with the long axis running east to west. • Place 40 to 50 percent of the total glass area on the south side of the house and minimize window area on east or west-facing walls. This will help provide year-round moderate temperature control without excessive solar heat gain in the summer. • Use a “time-of-day” room layout. Keep activity areas away from the east in the morning and away from the west in the afternoon, to avoid unnecessary heat gain.
DESIGN
THINK PASSIVE SOLAR • As energy costs rise, it is critical to use building orientation, window placements, stone floors, roof overhangs, reflective barriers and other techniques to control natural solar energy. • In colder climates, solar heat can be captured and stored in materials such as concrete or stone to be slowly released during the evening. An open floor plan optimizes the effect of passive solar heating or cooling. • Doors and windows should be placed to catch the prevailing breeze and allow cross ventilation. • Double and triple glass panes provide an insulating air space between the panes, reducing heat transfer. The metal oxide coating on Low-E (emissive) glass helps to keep solar heat out, and interior heat in.
Roselind Hejl
BUILDING ENVELOPE GREEN UP FROM GROUND UP FOUNDATION • Consider alternative materials for foundations: Insulated Concrete Forms (ICFs) are modular polystyrene forms which are stacked to create a foundation wall and concrete is poured into the void for rigidity. Also consider Durisol, it is a fossil fuel-free alternative to ICF’s, strong and energy efficient. • Reuse forms as much as possible: Modular forms are made for most foundation applications. Keep as much material out of the landfill as possible can reduce landfill costs. Clean and stack used forms after use and reuse them on another project. WALL SYSTEM • After your foundation is in place, the walls go up. Energy efficiency is achieved by increasing the R value and preventing air infiltration to reduce your energy use. You also want to use local and natural materials, and create as little waste as possible. • A greener alternate to the conventional ICFs, SIPS and Stud Framed walls are rammed earth and straw bale walls. Both materials offer high levels of insulation, perform well as wall systems and are cost effective.
BUILDING ENVELOPE
WINDOWS MATTER Here are a few things to look out for in windows: • Window Technology: the U-Factor and Solar Heat Gain Co-efficient; both are measures of the window’s energy efficiency. • The construction material of the window: the most energy efficient material is fibreglass because of its inherent ability to be a non-conductive material. The next best material is natural wood. Avoid vinyl and aluminum products, which transmit temperatures directly through their materials. • The type of window: whether encasement or double hung, contributes to energy efficiency. Encasement windows have a better seal than double hung windows. • Window Film: This a far more efficient solution than replacing windows. Window films block up to 99% of UV light that comes through windows, helping to cut down on heat gain. Depending on the window film, there is a 15 – 25% difference in heat loss. Window films can be tinted or clear, giving them the ability to block heat without blocking light.
Carrie Purcell
SUSTAINABLE MATERIALS THERMAL MASS Thermal mass is a property that enables building materials to absorb, store, and later release significant amounts of heat. These materials absorb energy slowly and hold it for much longer periods of time than do less massive materials. This leads to three important results: • There are fewer spikes in the heating and cooling requirements, since mass slows the response time and moderates indoor temperature fluctuations providing greater comfort. • A massive building uses less energy than a similar low mass building due to the reduced heat transfer through the massive elements. Thermal mass can shift energy demand to off-peak time periods when utility rates are lower. • Since power plants are designed to provide power at peak loads, shifting the peak load can reduce the number of power plants required. When looking for materials to build your next project, make sure high thermal mass is a necessary condition.
SUSTAINABLE MATERIALS
RENEWABLE, RENEWABLE, RENEWABLE • Use locally produced, and easily renewed, materials when possible. • Consider alternative building materials, such as rammed earth or straw bale – they are cost effective, sustainable, durable and even carbon capturing! • Concrete floors utilize the foundation material as finish floor, saving materials and labour. • Recycled wood floors are a very attractive re-use of materials. • Try avoiding carpets – hard surface floors do not hold dust, moulds, and allergens, and are very durable. • Use materials with recycled content when possible, such as cellulose insulation, Thermo-ply, and lumber composites.
Roselind Hejl
SUSTAINABLE MATERIALS
KEEP IT SAFE • Use products that are biodegradable, non-toxic, water based, and cold water compatible. • Avoid products that contain dyes, ozone depleting chemicals, heavy metals, formaldehyde, or known carcinogens. • Avoid solvent based finishes, particleboard, adhesives, some carpets, and other products that release volatile chemicals into the air. • Avoid polystyrene insulation usually found in Structural Insulated Panels (SIPs), there are plenty of affordable alternate insulation materials that do not contain toxic chemicals, such as rigid mineral wool, polyurethane and straw to name a few.
ENERGY EFFICIENCY
• Look for the Energy STAR rating when selecting appliances, fixtures, HVAC, water heaters and more. • Along with windows and HVAC, the other place you’ll find the Energy Star seal in a LEED-certified home is the appliances. • There are several Energy Star products on the market right now, ranging from refrigerators and dishwashers to dehumidifiers and air cleaners. • Regularly check up on and replace furnaces and hot water systems to get the most efficent new age technologies. • Replace incandescent lightbulbs with compact fluorescent lamps (CFLs). The lighting cost of the CFL is less than one-third of the cost for the incandescent. • Schedule an energy audit for more expert advice on your home as a whole.
Here are some great resources to support your project’s sustainable future: www.greenbuilding.com www.greenbuildingadvisor.com www.greenhomeguide.com For more information don’t hestitate to contact us at: www.n a t u re b ui l t wa l l. c o m