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There’s a lot to look for when looking at a home. So when someone says a home is green, what do they mean exactly?

Below are some of the questions you can ask to determine whether a home is green. Bear in mind, they address only some of the ways in which a home can be green. For more details, click on the logos

Is the home Energy Star® rated?
Is the home GBI (Green Building Initiative) certified?

Is the home Energy Star® rated?
Energy Star homes are 15% more energy efficient than homes built to code (the International Residential Code, 2004). These homes typically include energy-saving features that make them 20-30% more efficient than standard homes.

Make sure that the home has been verified by a third party verification service. And ask the seller for a copy of the Energy Star certificate.

QUESTIONS TO ASK:

1. Effective insulation
   • Is the insulation in contact with the air barrier behind it? (What, no air barrier behind it?)
   • Are the baffles at top plate properly installed to prevent air from seeping in?
   • Are the window and door openings properly sealed with foam or backer rod?
   • Is there insulation and rigid backing behind tubs placed on an exterior wall?
   • Is there rigid backing behind fireplaces, under stairs, behind attic knee walls, exterior chases and in skylight shafts?
   • Are the cantilevers properly blocked and insulated?
   • Are the plumbing and electrical penetrations sealed?
   • Does the insulation extend over the top plate of all the exterior walls?
   • Are the recessed lights rated air-tight?
2. High-performance windows
   • Do the windows and doors have low-E glass?
   • Do they have protective coatings?
3. Tight construction and ducts
   • Is the bottom plate sealed with caulk?
   • Is there an air-tight seal between the garage and living space?
4. Efficient heating and cooling equipment
   • Are the HVAC systems properly sized for the home?
   • Is there mastic on the HVAC unit and at the supply/return locations?
   • Is the duct work in attic installed at least one foot off attic floor?
   • Do all bedrooms have properly sized jumper ducts or air returns?
5. Efficient products
   • Is there at least one Energy Star appliance in the kitchen?
   • Are the lighting fixtures energy efficient?
   • Are Energy Star exhaust fans installed in the bathrooms?
6. Third-party verification
   • Has the home been inspected and tested by a third-party verification company?

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Is the home GBI (Green Building Initiative) certified?
GBI certified green homes are already Energy Star© rated. The GBI process is more involved and results in a “greener” home. If you’ve heard the expression “shades of green” related to green building, this is where it comes from.

For a home to be GBI certified it must earn a minimum number of points in these six categories plus additional points of the builder’s or homeowner’s choosing:

• Lot design, preparation and development
• Resource efficiency
• Energy efficiency
• Water efficiency
• Indoor environmental quality
• Operation, maintenance, and homeowner education

GBI is the verification system adopted by the National Association of Home Builders. Look for the GBI logo. And ask the seller for a copy of the GBI certificate.

QUESTIONS TO ASK:

1. Lot design, preparation and development
   • Was the site selected to avoid environmentally sensitive areas? Is it an infill site? A greyfield site? A brownfield site?
   • When preparing the lot, were natural resources conserved?
   • Is the home sited to optimize solar resources?
   • When the home was built, was it done so to minimize slope disturbance? Does the driveway align with the topography?
   • Is storm water managed properly?
   • Does the landscaping include only native plants? Does the landscaping require low water use?
   • When being built, was there an on-site supervisor to ensure green practices were implemented?
   • Were sediment and erosion control plans implemented?
2. Resource efficiency
   • Is the floor efficient and will it maintain the homes functionality over time? (Homes that become functionally obsolete are eventually torn down. Not green.)
   • Were advanced framing techniques, like 19.2” or 24” on center floor systems and bearing walls, used to reduce the amount of materials?
   • Was there a detailed framing plan with cut lists to reduce the amount of wasted lumber?
   • Are there any pre-cut or pre-assembled building components in the home?
   • Does the building design minimize degradation and weathering, like a covered entry and wide roof overhangs? Were termite resistant materials used?
   • Were any materials from pre-existing buildings or any salvaged materials used?
   • Is there any recycled content in the home?
   • Are there renewable materials in the home, like bamboo floor, cotton insulation products, or certified wood products?
3. Energy efficiency
   • Has the HVAC system been properly sized using the Manual J load calculation?
   • Is there continuous insulation along all outside walls?
   • Was an air sealing package implemented?
   • Are the windows Energy Star rated?
   • Was the HVAC design and installation verified by a third party verification service?
   • Are the ducts and plenums sealed with mastic?
   • Is there an Energy Star exhaust in all bathrooms?
   • Did the water heater design, equipment and installation must meet minimum requirements according to the third party verifier?
4. Water efficiency
   • Is there on-demand hot water delivery or control-activated hot water recirculation?
   • Is there a water heater within 30 feet of all bathrooms and kitchens?
   • How many Energy Star appliances are there?
   • Are the shower heads water-efficient?
   • Are all the toilets low-flow toilets (≤ 1.6 gpm/flush)?
   • If there is an irrigation system, is it a low-volume system using drippers and soaker hoses and not spray irrigation?
   • Does the irrigation system utilize different zones for yard and beds?
   • Is rain water collected and used?
   • Is there any innovative waste water technology?
5. Indoor environmental quality
   • Are the heating and water heating equipment direct vented?
   • Is there a tightly sealed door between living space and garage?
   • Were the particleboard, MDF and plywood products certified to have low formaldehyde emissions?
   • Are “green label” carpets and rugs installed?
   • Were the HVAC ducts masked during construction? Were they vacuumed before the system was turned on?
   • Were low-VOC paints and wallpaper used?
   • Is the kitchen range exhausted to the outside?
   • Is a humidistat installed to control the whole-house humidifier?
   • Is there a timer on the bath exhaust fans?
   • Is a moisture-resistant backerboard installed under the tile in wet areas?
   • Are the cold water pipes in unconditioned spaces insulated with ½” insulation?
   • Are the ducts and plenums in unconditioned spaces insulated?
6. Operation maintenance and homeowner education
   • Is there a manual available to the owners on the use and care of the home?

Remember, the greenest homes are certified green. Ask to see the certification.

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