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"The type and level of activity in a room determine how much lighting is needed," Nelson said. "For example, a kitchen should generally have more lighting than a bedroom."
After deciding how much lighting a room needs, you must determine which bulb will provide this amount most efficiently. The efficiency of a bulb is related to the number of lumens it produces, not its wattage.
"This is where most people make mistakes," Nelson said. "They purchase high wattage bulbs, assuming that they are getting more lighting capacity."
Wattage measures how much energy a bulb will use. Lumens, on the other hand, indicate how bright a bulb is.
So, the most energy efficient source is the bulb that gives you the most lumens for the fewest watts.
For example, a 100-watt bulb produces approximately 1,800 lumens, or 18 lumens per watt. A 60-watt bulb, on the other hand, produces only 840 lumens, or 14 lumens per watt.
"In the above example, the higher wattage bulb is more efficient, but this isn't always the case," Nelson said. "You must divide lumens by watts to determine efficiency."
Nelson said that the greatest drain on energy dollars is over-lighting.
"Three-way lamps are an efficient lighting source if you use a three-way bulb and keep it on the lowest setting when you do not need bright lighting. Using a single high wattage bulb in a three-way lamp wastes energy as well as money.
"In areas which require more lighting, use one high wattage bulb (100-watt) rather than two 60-watt or three 40-watt bulbs. The single high wattage bulb will produce comparable lighting and use less energy," Nelson said.
In general, compact fluorescent light bulbs are significantly more energy efficient than incandescent light bulbs and can be purchased at your local hardware store or from specialty outlets.
"Exhaust fans are rated by their air moving capacity in cubic feet per minute, or CFM," Walter said. "The rules of thumb relate the required CFM to the volume of the space to be ventilated."
To size an exhaust fan for your kitchen, multiply the volume in your kitchen (length X width X ceiling height) by 0.20. A 12 X 12 foot kitchen with an 8-foot ceiling would require an exhaust fan rated at 230 CFM.
According to Walter, kitchen exhaust fans should move at least 200 CFM as a practical minimum. A bathroom exhaust fan should move 0.13 CFM per cubic foot of space, with a minimum of 50 CFM.
"Exhaust fans must be vented to the outside, not into an attic or crawl space," Walter said. "The venting duct should be as short as possible and have few right-angle bends. If you use a flexible ducting material, pull it tight between the exhaust fan and the vent terminal while avoiding sharp bends and cut off any excess material. Improper ducting can reduce exhaust fan air flow by 50 percent or more.
"I recommend a backdraft damper to prevent cold air from entering through the exhaust fan when it is shut off," he said.
This damper can be located at the fan or at the end of the vent.
"In Kansas, solar south varies from eight to 11 degrees east of compass south," Snead said. ''A good rule of thumb would be to turn 10 degrees east of compass south. This slightly reduces the exposure to hot western summer sun and increases morning heating in the winter,'' he said.
Though this is the optimum situation, homeowners do have some flexibility in orientation, according to Snead.
"Shifting the orientation up to 20 degrees to the east or west of solar south reduces the annual average solar radiation falling on your south wall by only about 10 percent," he said.
"The size or capacity of water heater you need is based on the maximum amount of hot water you consume during any one-hour period," said Doug Walter, president of Kansas Building Science Institute, Manhattan. "This is called your peak hour demand.
"To determine the peak usage hour for your family, list all the water consuming activities during that period," Walter said.
Typical hot water consumption in gallons per usage for various activities is as follows: shower, 20; bath, 20; shaving, 2; hands and face washing, 4; hair shampooing, 4; hand dishwashing, 4; automatic dishwasher, 14; food preparation,, 5; automatic clothes washer, 32.
The peak for one family might occur in the morning, and consist of three showers (20 gallons each, 60 gallons total), hands and face washing (5 gallons), shaving (2 gallons), and food preparation (5 gallons), for a total of 72 gallons.
"A water heater can provide more than its storage capacity during the first hour of operation, because it can also heat the water during this period," Walter said.
"This capacity, the total gallons of hot water the heater provides during this first hour, is referred to as the first-hour rating," he said.
In the sample above, a water heater with a first hour rating of at least 72 gallons would be required.
"Residential water heaters are most commonly available in 20, 30, 40 and 50 gallon capacities with first hour-ratings ranging from 22 to 100 gallons," Walter said.
"Gas and propane water heaters typically have higher first-hour ratings than electric heaters of the same storage capacity," he said.
"To eliminate this problem, you should periodically inspect supply and return duct work," Hayter said. "Tape any cracks with foil tape or seal with caulking or mastic.
"Detecting leaks is a simple procedure, and there are several methods you can use," Hayter said.
Shining a flashlight in the duct and observing where the light comes out is one method.
You can also use smoke from stick incense or smoke pencil to detect leaks. With the furnace fan running, hold the smoke near suspected leak areas.
"If there is a leak, you will notice obvious disturbance in the smoke," Hayter said. "A leak in a supply duct will blow the smoke toward you. If the leak is in a return duct, the smoke will be sucked into the duct."
Hayter said sealing the supply and return duct work in unconditioned areas such as crawl spaces and attics is important when guarding against leaks.
"Holes, leaks and duct work which has come apart will allow conditioned air to seep through, thus heating or cooling the unconditioned areas," he said.
Due to normal home construction practices, the return duct is more prone to leakage than the supply is. Sheetmetal is nailed over the open portion between wall studs and floor joists. Gaps between the metal and wood, plus holes for electrical wiring and plumbing, allow unconditioned air into the system.
"The unconditioned air that enters the system through the return duct dumps additional loads on your equipment," Hayter said. "Imagine 130 attic air returning to the cooling system instead of 75 conditioned air. Your air conditioner would have to run much longer to cool the space."
"Sone ratings for exhaust fans typically range from a low of one to a high of seven."
According to Walter, the smaller the number, the quieter the fan.
However, the quietest fans move the least amount of air.
"Don't sacrifice adequate air moving capacity for quietness," Walter said. "Make sure you choose a fan that can do the job.
"Once you have determined the capacity of fan you need, compare sone ratings on fans of equal capacity and choose the fan."