Whether you are building or renovating, the green homes approach to housing reduces environmental impacts, reduces long-term building operations and maintenance costs, increases marketability and building value, and results in healthier indoor environments. Perhaps the most important aspect of building a green home is that it is not an “all or nothing” process. When carefully selected and implemented, even modest measures can result in significant conservation of resources. Green homes are also uniquely local as climates, customs, availability of materials and preferences vary so much throughoutCanada.
1. Living closer to amenities means greener transportation options. When choosing your property, consider access to work and amenities. Bicycle paths and walking distances to basic services can make a big difference to your gas bill.
2. Choose building sites that make eco-logical sense. Why build on the most beautiful spot? The most attractive place, a bluff area, ocean or creek bank, is often the most ecologically sensitive. And most of your time at home is spent inside your house.
3. Cluster buildings and share services. Clustering buildings closer to each other reduces the amount of land used and encourages sharing of driveways, parking areas, water, waste and power lines.
4. Minimize driveways and paved, compacted areas. Minimizing the driveway reduces compacted surfaces and storm water erosion, helps preserve open space, and reduces resource consumption.
5. Protect the natural landscape. Indigenous landscaping supports wildlife and biodiversity far better than conventional turf and does not require irrigation and chemical treatments. Traditional grass lawns are an expensive fashion hangover from Louis the 16th.
6. Respect and create community. Development patterns can either inhibit or contribute to strong community and neighbourhoods. nstruction
7. Integrated building design equals construction and operating cost savings. Integrated design includes the general contractor in early discussions with the architect, engineer, and other agencies.
8. Design for a smaller, more compact house. Sufficient is efficient! The size of your home has a greater impact on energy and resource use than any other factor. Building small makes so much sense; less cost, less materials, plus less housework! The trick is to achieve the house that you truly need, that is comfortable and feels good.
9. Use green building materials.
10. Optimize building material use by using standard dimensions. Design your home to work with standard sized materials: for example, 4×8 sheets of plywood, OSB, and drywall. Also consider “advanced framing,” a design technique that reduces or eliminates structurally unnecessary framing elements in wood framed buildings.
11. Reduce, reuse, recycle and resell waste materials. e
12. Design to reduce energy consumption. Green buildings use less than half, and sometimes as little as a quarter, of the energy as their conventional counterparts. Much of this is the result of an improved building envelope with better windows, draft sealing, more insulation, and energy-efficient appliances, but doing nothing more than simply creating smaller houses can save tremendous amounts of energy. Do design for solar gain through siting and window placement and consider solar water heaters, even off-grid solar and wind electricity systems.
13. Design your house to consume less water.
14. Build to last a long time.
15. Reduce indoor air pollution. The average Canadian spends approximately 90% of their time indoors. Many products such as vinyl flooring or particleboard contain chemicals that “off-gas” for weeks, months, even years after installation. Other products such as carpeting readily trap dust and odours and release them over time. House dust is now recognized as a major source of toxics ingestion for children. Building materials such as particleboard or drywall can also support growth of molds and bacteria, particularly if they become damp, potentially causing allergic reactions, respiratory problems and persistent odours – symptoms of “sick building syndrome.” Carefully examine the options for less harmful materials such as stone, tile, concrete, wood, or natural linoleum flooring, and water-based, zero or low VOC paints and finishes, and design for a continual source of fresh air.
Green building materials
(Greater Vancouver Regional District Best Practices Guide suggestions)
1. Select materials that will not adversely affect human health. Examples include zero or low VOC interior paints and flooring. Carpets generally have a high VOC and harbour dust and other allergens
2. Select materials that contribute to operating energy efficiency. Building envelope materials such as insulation, air barriers, and glazing (window) assemblies that contribute to efficient home heating and lighting etc.
3. Select durable lifelong materials requiring little or no additional finishes and minimal maintenance. Examples include exterior siding that doesn’t require paint, flooring materials such as wood and ceramics instead of sheet plastics, or structural materials such as concrete floor slabs that omit the need for conventional flooring. Roofing examples include clad sheet metal and 35-year asphalt shingles instead of wood shingles and low quality asphalt roofing.
4. Consider omitting unnecessary materials. Reduce quantities of all materials. Focus on compact, smaller houses designed to fit standard-dimension materials.
5. Select salvaged and reusable building materials. Examples include lumber, flooring, cabinets, certain plumbing fixtures and hardware. Make sure these materials are safe (test for lead paint and asbestos), and don’t sacrifice energy efficiency or water efficiency by reusing old windows or toilets.
6. Select materials manufactured from renewable resources and harvested in a sustainable manner. Use lumber from independently certified well-managed forests. Avoid lumber products produced from old growth timber unless they are certified.
7. Select materials that have recycled content and are recyclable. Building products bought new but made from recycled materials reduce solid waste problems, cut energy consumption in manufacturing, and slow down natural resource extraction and consumption.
8. Select materials that require minimal manufacturing and processing, and have low embodied energy. Heavily processed or manufactured products and materials require more energy to produce. As long as durability and performance will not be sacrificed, choose low-embodied-energy materials. Although off-gassing occurs in both
materials, traditional linoleum has a service life of 30 to 40 years and embodied energy of 17 MJ/kg as compared to vinyl flooring with a lifespan of 8 to 15 years and embodied energy of 98 MJ/kg.
9. Select locally manufactured materials. Our pine, alder, maple, and other local species produce beautiful cabinets, floors, trim and furniture. Locally harvested and milled fir, cedar, and hemlock also provide structural components.
10. Select materials that can be disposed of safely. For example, metal roofing has manufacturing impacts but can be recycled into newly manufactured steel products; cedar siding can be composted and/or used for kindling. On the other hand, sheathing, decking and foundation materials made from CCA (chromated copper arsenate) pressure treated wood, leach toxic metals into the ground and water (and the air if incinerated).
Clean indoor air strategies:
• Install hard surface flooring (wood, cork, concrete, tile, linoleum) as much as possible. They are durable, easy to clean and won’t harbour mold, dust, dust mites, and other allergens.
• Minimize carpeting (holds allergens and off-gasses) and vinyl products (off-gasses).
• Pay particular attention to adhesives and sealants, paints and coatings, and composite wood. Use low or no-VOC interior paints and finishes (under 150 grams/liter).
• Exhaust odours and humidity with fans in the bathrooms and kitchen. Keep fresh air coming into your home with opening windows that provide good cross ventilation, a whole house fan, or a mechanical ventilation system.
• Wood burning is the traditional way to heat homes. The resulting smoke compromises indoor and outdoor air quality and can be mitigated by using well seasoned, dry wood and newer, efficient wood stoves. Always make sure that you have a fresh air source into your home when your stove is operating.
Space efficiency strategies:
• Share the use of each space. A home office and guest bedroom is a common combination. The hall or stairway can be a library or art gallery; a landing can be a reading nook.
• Build furniture into rooms. Cabinets, bookcases, benches and eating nooks can be recessed into inner walls. Large storage drawers can be installed under the stairs.
• Avoid showcase rooms and heat wasting vaulted entranceways and front rooms. Why have a formal living and dining room when most people gather in kitchens and family rooms?
• Provide ample storage. When people say they want a “bigger house” they may only need more storage.
• Plan for flexibility. House designs should allow for changes in lifestyle. A young couple may have children. Grown children will leave the nest. A business could be born in the kitchen and grow in the guest bedroom. Canada Mortgage and Housing Corp. has some great ideas on planning for change such as easily renovated plumbing, wiring and wall designs.
Energy conservation in appliances and fixtures:
• Washing machine: Front loaders use way less energy, water and soap than top loaders.
• Air-conditioner: On the coast, air conditioners are generally unnecessary. Opening windows for natural, cross ventilation and ceiling (paddle) fans to increase airflow is enough. Roofs and other surfaces such as playgrounds, courtyards and paths can be designed to stay cool in summer through the use of light-coloured surfaces or vegetation.
• Dryer: Try an old fashioned solar-power clothes line or an indoor clothes rack.
• Lighting: Replace lights that are left on for long periods with compact fluorescent bulbs and explore the new LED technology. Check the Energy Star ratings and colour tone for either type of bulb. Minimize outdoor lighting and consider using ground level lighting and motion sensors. Address safety concerns by designing outdoor spaces and landscaping with night safety in mind.
• Hot water heater: Demand heaters may work much better than conventional tanks.
• Fridge and dishwasher: For any new appliance, look for Energy Star or Energuide labels, and let dishes air dry.
• Stereo systems and electronics, including computers: Attach these to a power bar so that when you turn them off, they really are off.
Windows:
Locate more of the windows on the south side than other orientations and consider using window blankets on winter nights. Generally, low solar-heat-gain-coefficient (SHGC) glazings are designed to reflect heat, but admit light, and are used on east and west orientations. High SHGC glazings make sense on south orientations where windows can capture the lower angle of the winter sun for passive solar heating and day lighting. This keeps buildings warmer in winter and cooler in summer, saving energy.
Water conservation strategies:
• Purchase water-conserving appliances such as dishwashers, front-loading clothes washers, and on-demand water heaters.
• Install low flow showerheads, faucet aerators and low flush toilets. Consider dry fixtures such as composting toilets and waterless urinals.
• Use efficient irrigation systems (drip irrigation, soaker hoses and rain/moisture sensors) and use native plants that require very little watering.
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Excerpted from Living Green on Cortes: Building Your Home, a Friends of Cortes Island production available for download as a pdf file at www.watershedsentinel.ca/library.htm (go to Special Features).
Further Resources
Best Practices Guide: Material Choices for Sustainable Design. GVRD (Greater Vancouver Regional District), 2001
The New Ecological Home: Complete guide to Green Building Options. Chiras, CGP
The Home Energy Diet. Scheckel, NSP, 2005
Homes that heal and those that don’t. Thompson, NSP, 2004
Green Development: Integrating Ecology and Real Estate. Rocky Mountain Institute. John Wiley & Sons, Inc., 1998
The Natural Step for Communities How Cities and Towns can Change to Sustainable Practices. James/Torbjorn, NSP, 2004
Canada Mortgage and Housing Corporation. This site offers a very large library with many downloadable documents on design, construction, sustainability, affordable housing, and so on. You can also order free booklets, technical studies, and much more. www.cmhc-schl.gc.ca/en/inpr/
Green Buildings BC, Guide to Green Building Resources, www.greenbuildingsbc.com/new_buildings/resources_guide/