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"First, inspect the envelope of your home," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
Various opportunities exist for improving energy efficiency, such as insulation, radiant barriers and weatherstripping.
The envelope is composed of your roof, ceiling, walls, floors, windows and doors. Insulation levels as high as R-38 in the attic are appropriate. It is permissible to mix insulation types, such as covering fiber glass with cellulose.
"Any exposed ductwork in the attic also should be sealed an the outside of the insulation," Hayter said.
Weatherstripping and caulking reduce both heating and cooling costs. Inspect existing weatherstripping for wear and possible replacement.
"In addition to caulking window and door frames, inspect for hidden cracks such as those that exist along foundations or where exterior wiring or air conditioning lines may penetrate the wall," Hayter said.
South-facing windows can be a real benefit during the heating season, but can add significantly to your cooling load.
"It is preferable to block the sunlight before it penetrates the window," Hayter said. "Although a drape will delay the instantaneous solar gain, it's more effective to stop the sunlight completely by using exterior shading or reflective blinds."
Deciduous trees provide an excellent means for natural shading in the summer yet allow exposure of the window in the winter. Removable exterior awnings can provide a similar advantage.
"Unventilated attics can reach high temperatures during the summer, contributing considerably to the cooling load in the home," Hayter said.
Attics should be properly ventilated by having sufficient openings along the low side of the attic, such as in soffits as well as openings along the high side of the roof for exhaust.
For ventilation, you should have at least one square inch of free opening for every square foot of attic space.
"Openings should be distributed equally between the low and high sides of the attic," Hayter said. "Remember that screens and louvers block up to 50 percent of the ventilation area."
You can move air in and through the home without relying on your air conditioner. When the outdoor air is cool yet the home is warm, a whole-house fan which draws air through open windows and discharges into the attic may provide all the cooling necessary.
Additional attic ventilation is necessary when using a whole-house fan.
"You should have one square foot of free opening for every 750 cubic foot per minute (cfm) of air moved by the whole-house fan," Hayter said.
Within the home, you can provide some cooling relief with portable fans or ceiling fans.
Household appliances can add considerably to the cooling load in your home. Your refrigerator condenser coils should be cleaned at least twice annually.
"Inspect the gasket around the refrigerator door to assure that it has not worn and needs to be replaced, " said Richard B. Hayter, director of Engineering Extension at Kansas State University.
Your cooking range and clothes dryer should be vented to the outdoors as should exhaust fans in bathrooms.
Heat loss from your water heater adds both to your water heating costs as well as air conditioning costs. A water heater that is warm to the touch should be insulated with a water heater insulating jacket.
"Thermostats on water heaters should be turned down to provide hot water at the tap no greater than 140 degrees," Hayter said.
You should prepare your furnace for summer by replacing or cleaning the air filter, and lubricating, where possible, any bearings on the blower or motor. You may wish to consider extinguishing the pilot light if your furnace is equipped with a pilot. Many new furnaces use an electronic device for igniting the flame whenever the thermostat calls for heat rather than using a standing pilot light.
"This will probably not result in a significant reduction in your gas costs, however, the pilot does contribute a small amount of heat to the home which then must be removed by the air conditioner," Hayter said.
Contrary to some earlier information, extinguishing the pilot light will not shorten the life of the furnace. Be sure that if your furnace is equipped with a central humidifier that it is turned off, drained and cleaned.
An air conditioner needs adequate air flow through the condenser for the unit to operate at maximum efficiency. Plantings and fencing should be no closer than three feet to the condensing unit.
"The condensing unit should be cleaned annually by carefully removing any debris from the fins of the condenser," Hayter said.
You may wish to consider hiring an air conditioning service contractor to clean your condenser thoroughly, particularly if it has not received maintenance in the last two or three years.
Service contractors will use a variety of cleaning solutions to remove any buildup on the condenser fins as well as straighten any fins which may have been damaged, lubricate any exposed bearings, and check for appropriate refrigerant levels in your air conditioner.
Taking advantage of these and other opportunities should help to reduce your cooling this summer.
High levels of many indoor pollutants are indicated by physiological symptoms.
These symptoms often include headaches, nausea, dizziness, eye irritation and respiratory infections. When you experience these symptoms regularly inside your home, but feel them diminish or go away when you are outside your home, poor air quality may be the cause.
"Because air sampling and analysis are difficult, expensive and often ineffective unless the type of pollutant is known, identifying and eliminating a pollutant usually is done by trial and error," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
You can help this process by identifying conditions or circumstances that seem to cause or increase the irritation. When did you first notice the irritation? Can any change in the home be tied to that point in time, such as installation of new drapes, new carpet or a new furnace? Does the irritation become worse when the furnace is running? Is it worse in one part of the house? Do certain weather conditions affect the irritation?
Some indoor pollutants may give no physiological evidence of their presence.
"Radon gas, for example, is colorless and odorless and causes no immediate symptoms, but may cause lung cancer years after the exposure," Walter said.
Radon levels in a home are easily measured using inexpensive test kits that are exposed to the air in the home for about three days. Contact your county extension office or county health department for more information on obtaining radon test kits. Some county extension offices have the test kits for sale.
If you have any combustion appliances in your home, it is wise to install an electronic carbon monoxide detector to alert you if carbon monoxide levels ever become elevated to dangerous levels. These detectors are readily available at many hardware and building supply stores and at larger department stores.
"The most energy efficient doors are those that seal tightly when closed," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
This requires a quality weather-stripping system and a door that resists warping.
The insulating value of the door is also important.
"Metal and fiber glass doors are available with urethane foam cores that provide R-values up to 4.4, compared with an R-2.1 for a solid wood door," Walter said.
"A metal door has the added advantage of using magnetic gasket weatherstripping that works much like the seal on a refrigerator door."
It's important to keep door-related energy costs in perspective.
"In Kansas, a typical solid wood door with average-fitting weather-stripping contributes only about $9 a year to heating costs," Walter said.
"This term, like wind chill, is an attempt to combine various environmental conditions into a single index indicative of cur comfort or discomfort," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
The heat index combines relative humidity and dry bulb temperature (temperature of the air) into a single measure. The index is given as an "apparent temperature."
"The apparent temperature indicates the way a person would feel under various temperatures and humidities compared with a standard or specified condition," Hayter said.
For example, at a temperature of 90 degrees and 60 percent relative
humidity it would "feel like" 100 degrees based on the apparent temperature.
The apparent temperature was developed in 1979 by R.G. Steadman at Colorado State University.
"Steadman used a meteorological standard condition for defining the point of comparison in developing the index," Hayter said.
The index was based on research involving numerous test subjects as well as physiological measurements in response to various environmental conditions.
"Certainly individual differences will significantly affect the sensation you may experience," Hayter said.
Similarly, your clothing and activity level have a major influence. Therefore, the heat index is only an approximate indication of the severity of the hot weather as it may affect you.
"It can indicate, however, the potential stress you may experience when you are exposed to high temperatures and humidities," Hayter said.
Yes.
"For any residential structure which is heated, the edge of the slab should be insulated," said Bruce Snead, extension specialist in residential energy at Kansas State University.
This insulation should isolate the concrete from the cold outside air and frozen ground below grade down to the frost line.
"Insulation underneath the slab near the perimeter is also recommended," Snead said.
'This insulation will keep the floor warmer, making it more comfortable for people."
Whether to insulate under the floor depends on a number of factors.
If the slab is covered with insulating materials and finish materials such as carpet, no insulation is needed underneath.
"You definitely should insulate if there are any buried or in-slab heating systems," Snead said.
If the slab area is small or is exposed on two or more sides, insulating underneath the entire slab will reduce heat loss and improve comfort. For a slab used as direct gain passive solar thermal storage, insulation will reduce heat loss to the soil and keep the floor more comfortable.
"With large slabs, a four-foot wide band of insulation under the perimeter of the slab may be sufficient," Snead said "Remember, there is only one opportunity to install this insulation."
Expanded or extruded polystyrene tend to be the best products for this application. Generally, one inch of thickness is adequate for most under-floor installations. Insulation at the vertical slab edge should be a minimum of two inches thick.
'This insulation will need to be protected from sunlight and weather where it is exposed above grade," Snead said.