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"For best year-round energy performance, the long axis of your house should run east and west, and the facade with the most window area should face within 30 degrees of true south," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
South-facing windows are net energy gainers. That is, during winter, they admit more heat from solar energy than they lose.
"In summer, you can protect them from heat gain with a properly-sized overhang or other shading device," added Walter.
Windows facing any other direction are net energy losers. Unshaded east- and west-facing windows admit unwanted solar heat during summer. Furthermore, they are difficult to shade effectively.
"Don't exclude windows on the east, north, and west sides of your new home, however," said Walter. "They provide natural light, cross-ventilation, views, and emergency exit from bedrooms. Simply limit the size and quantity of windows that do not face south."
"The vast majority of radon in a home comes from the soil underneath and around the foundation," said Bruce Snead, extension specialist in residential energy at Kansas State University. "It can enter through a variety of possible openings, like open soil, open sumps, floor cracks, joints between foundation elements, and any other penetrations through the foundation, such as for plumbing or utilities."
Radon enters the home primarily because of air pressure differences which create a suction effect.
"This suction can have a number of causes," Snead said, "warm air rising through the house, the operation of fans or equipment which take air out of the home or cause air pressure imbalances, and weather effects, such as wind and barometric pressure changes."
"A concrete slab floor should be insulated first at the edge of the slab where it is exposed to the outdoor air and then down the face to the frost line or below," said Bruce Snead, extension specialist in residential energy at Kansas State University.
A foam board type of insulation is most suitable, usually extruded polystyrene with enough thickness to achieve an R-value of at least 12.5.
"Insulating beneath the floor depends on a number of factors," Snead said. "If the slab is to be covered with carpet or other insulating materials, you don't need insulation underneath."
"You should definitely insulate the slab if you have any buried or in-slab heating systems, and do so in consultation with the manufacturer's and installer's recommendations," Snead further advised. "If the slab area is small or exposed on two or more sides, insulating the sides and underneath will tend to keep the slab warmer."
If the slab is to be used for direct-gain passive solar storage, insulation will reduce the heat loss to the earth below and keep the floor more comfortable. Insulate wherever the sun will strike the floor and where desired for comfort.
In larger slabs, a four-foot-wide band near the edge may be sufficient.
"If the slab rests on damp, wet soil, it will tend to lose heat more rapidly and insulation will help retard this loss," Snead said. "In general, one-inch thickness of polystyrene should be adequate for most installations."
"Both horizontal and vertical shading can be created by plants, but most will require a support structure," said Bruce Snead, extension specialist in residential energy at Kansas State University. Horizontal shading by wisteria, Concord grapes or roses requires a strong arbor or trellis. Silver lace vines will grow on rope with some training of the tendrils.
"Vertical shading of the west wall and windows is accomplished by training vines to grow on lattices or a network of string or cord," Snead said.
Virginia creeper, euonymus, ivies, and morning glories are some good possibilities for vertical shading.
"Overhangs, awnings, and some other fixed shade devices are somewhat effective," Snead said. "As the sun's path drops in August and September, more sun is allowed to shine in. This adds to the cooling costs."
Another advantage of using plants to provide window shading is they are better matched to the cooling season. Plants leaf out at the beginning of the cooling season and remain that way until late September, thus providing shade during the hottest months.
"Of course, plants require care and may need to be 'trained' to grow in certain patch if they are to be effective," Snead said.
Contact your county extension office or local nursery for more information about shading with natural vegetation.
"Turning lights off when they are not needed will always save energy," said Gene Meyer, extension mechanical engineer at Kansas State University. "The momentary power "surge" caused by turning a light on is so small and so brief, it won't even register on your electric meter."
Frequent switching of fluorescent lamps, however, will shorten their life, eating into the savings of turning them off. Even so, fluorescent lamps need only be off a short period of time for the energy savings to exceed the cost of reduced lamp life. Thus, if you plan to be out of a room for more than about 15 minutes, shut fluorescent lamps off.
"Practically speaking, incandescent lamps are not affected by frequency of switching," Meyer said. "You should shut them off whenever they are not needed, no matter how short the time period."
"Ventilation is one possible strategy you can use to reduce radon levels, but the solution you are describing may actually worsen your situation," said Bruce Snead, extension specialist in residential energy at Kansas State University.
"If you blow air out of the basement, you are creating a negative air pressure, or sucking action, on the foundation walls. You could increase the level of radon in your basement."
Snead said an initial screening measurement of 7.5 picocuries warrants a second measurement to verify levels before taking action.
"A long-term—three-month or one-year—alpha track test is one course of action to take after receiving these kinds of initial test results," he said. "Another is a second short-term test in the same location. If the average of the two short-term tests or the long-term result is four or more picocuries per liter, EPA would recommend taking action to reduce levels.
"If you want to use ventilation or a through-the-wall fan to temporarily reduce radon levels, use positive air pressure," Snead said, "by forcing fresh air into the space from the outside."
We have been advised to begin a chemical treatment program for the closed loop hot-water heating in our school. What should we use?
"Chemical treatment is beneficial for most closed-loop heating systems," said Gene Meyer, extension mechanical engineer at Kansas State University.
Corrosion in the system reduces equipment efficiency by limiting heat transfer and can leading to premature failure of the pipes and boiler. Chemicals can help control this corrosion.
Today's treatment chemicals often include buffered nitrate, molydate, and organic blends. You should contact a supplier of boiler treatment chemicals for specific recommendations. Factors that should be considered when choosing specific products include the age of the system, the materials contained in the system, and the tightness of the system.
If the system has leaks, these should be repaired prior to adding chemicals.
Chemically treating your water system requires little maintenance, but periodically testing the water assures that chemicals are at required concentrations," said Meyer. "Use a full-service supplier who provides complete operator training and follow-up testing."
"Chemical treatment is beneficial for most closed-loop heating systems," said Gene Meyer, extension mechanical engineer at Kansas State University.
Corrosion in the system reduces equipment efficiency by limiting heat transfer and can leading to premature failure of the pipes and boiler. Chemicals can help control this corrosion.
Today's treatment chemicals often include buffered nitrate, molydate, and organic blends. You should contact a supplier of boiler treatment chemicals for specific recommendations. Factors that should be considered when choosing specific products include the age of the system, the materials contained in the system, and the tightness of the system.
If the system has leaks, these should be repaired prior to adding chemicals.
Chemically treating your water system requires little maintenance, but periodically testing the water assures that chemicals are at required concentrations," said Meyer. "Use a full-service supplier who provides complete operator training and follow-up testing."
"Most detectors measure radon," said Bruce Snead, extension specialist in residential energy at Kansas State University. "They capture an amount of radon in the detector similar to that present in the air in the room."
For most detectors this is done passively, by the process of diffusion. This means radon gas leaks into the detector until it has reached a level equal to the level in the room. The amount of time this takes depends on the design of the detector, but usually no less than two days of exposure time.
"When the test period is over, the homeowner closes the detector and sends it to the originating laboratory for analysis," Snead said. "The lab then determines the amount of radon in the detector and sends a report back to the homeowner."
"There are temporary caulking products," said Doug Walter, president of Kansas Building Institute, Manhattan. "They are known as liquid or peelable caulks."
Walter said these types of caulk can be applied as a clear gel that dries to a nearly invisible bead.
"After seven to l0 days, you can peel this plastic bead off in much the same way you would a strip of tape," Walter said. "Temporary caulks are available in most hardware stores in squeeze bottles or conventional tubes."
Because most temporary caulks are water soluble, Walter said manufacturers do not recommend them for exterior use or where they are exposed to moisture.
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