Q: I am planning to design and build a new house, and I want it to be energy-efficient. I want to try to make it a LEED house so I get reduced property taxes. What exactly is a LEED house and is it efficient?
A: LEED stands for Leadership in Energy and Environmental Design. LEED is a certification procedure developed by the U.S. Green Building Council (www.usgbc.org) to promote environmentally responsible and sustainable housing. These houses are not only efficient from energy and material standpoints, but they are more healthy to live in.
Building a LEED house will generally cost more than building a house to typical building codes. When you consider the energy and water savings and possible tax abatement, a LEED house will quickly pay back its higher initial cost. Contact your local tax authorities to see if a LEED house qualifies for any local tax abatement.
Even though this certification process was developed by a U.S. organization, it is recognized and used by many countries throughout the world. Environmental and energy issues are no longer just local or domestic. They are global issues that affect the entire planet.
In order to build a LEED house, you or your builder must apply for LEED certification through the USGBC. You must be able to verify the types of materials, equipment and appliances used throughout the new house, and it must be inspected by a certified LEED inspector. There is a fee for the inspections based upon the size of the house.
A house is given LEED points for various criteria. For a house, there are 108 possible points. If a house reaches 30 LEED points, it is a LEED "certified" house. At 50 points, it is certified "silver." At 70 points it is "gold" and "platinum" at 90 points.
It is not difficult to build a LEED house. Deltec Homes (toll-free 1-800-642-2508; www.deltechomes.com), makers of circular panelized houses that a homeowner can build himself, recently earned a platinum certification for a house built in New Orleans. This circular house looks similar to their other houses, and it was built in only about 100 hours.
Energy efficiency features gain the most LEED points (a maximum of 16). For example, extra insulation earns one point. Reducing air leakage from 0.35 air changes per hour to 0.15 yields two points. Installing windows that are 20 percent more efficient than Energy Star (www.energystar.gov) requirements provides two points. A better furnace gets three points.
Saving water is another area that affects the environment. These yield one point each: capturing rainwater for irrigation, installing a graywater system, and installing low-flow showerheads, toilets and bathroom faucets. If you install super-efficient ones, you get two points.
Many items that gain LEED points seem pretty typical today. Installing compact fluorescent bulbs in 80 percent of the light fixtures gets one point. Using low-VOC paint for less air pollution and healthier indoor air quality earns a point.
Proper ventilation for whole-house fans
Q: You recently wrote about installing a whole-house fan and mentioned there should be adequate exhaust ventilation in attic. How much ventilation is adequate, and where should the exhaust vents be located?
A: The minimum amount of exhaust attic ventilation is about 1 square foot of net free vent area for each 750 cfm (cubic feet per minute) of fan air flow capacity. The net free vent area will be listed on the vent packaging.
The best location for the exhaust vents are at the roof ridge, and it is easy to install ridge vents. Ridge vents are also most effective for venting an attic when the whole-house fan is not running.
Send inquiries to James Dulley, St. Petersburg Times, 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit www.dulley.com.