Ask Energenie

October 1998

Table of Contents

1. Is there a simple way to stop a basement from leaking? I get water in mine every time it rains hard.
2. What are the suggested R-values for the various components of a new home?
3. What services should be included in a furnace tune-up?
4. The new compact fluorescent bulbs that can be installed in incandescent fixtures look like a good way to save energy, but they are expensive. Are they cost-effective?
5. I'm going to have my walls insulated. Are there any options to the plastic plugs that are used to fill the holes?
6. What should I do to close up a whole house fan for the winter?
7. What is the cost of operating a home computer system?

| Return to Ask Energenie home page |

1. Is there a simple way to stop a basement from leaking? I get water in mine every time it rains hard.

"There is a way to reduce basement leaks, but it may not eliminate them," said Doug Walter, president of Kansas Building Sciences Institute, Manhattan.

Basement leaks correspond to duration and intensity of rainfall. Large amounts of water exert enough hydrostatic pressure in the soil surrounding a basement to cause leaks if there is a sufficiently large crack in your basement wall.

"You can reduce hydrostatic pressure by directing rain water away from your basement walls," Walter said. "The first step involves the installation of a properly sized guttering system."

Downspouts should have extensions or ground gutters that direct runoff at least two feet from the foundation.

"Keep the guttering system clean so that it function properly," he said.

Soil should slope away from the foundation to drain the rain that directly strikes the ground. A grade of a least 5 percent for a distance of 15 feet is ideal. Dense turf grass also aids in drainage.

If you have a particularly troublesome leak, Walter suggests installing a foundation apron. This is an 18-inch-wide concrete apron poured at grade level around your home's foundation, or just where leaks persist. The apron directs water away from the foundation, reducing hydrostatic pressure along the basement wall.

Back to Top

2. What are the suggested R-values for the various components of a new home?

"The best, current information suggests the range of R-values in the table below," said Bruce Snead, extension specialist in residential energy at Kansas State University.

"The value in the range you should pick depends on where you live in the state," Snead said. "Lower R-values are more appropriate in southeastern Kansas, while homeowners in northwest Kansas should consider higher R-values. Those living in the central part of the state should aim at a value somewhere in the middle of the range."

R-value is the measure of a substance’s resistance to temperature change.

"Select a building system that will provide R-values within or above these ranges and see that materials are installed so as to create a well-sealed structure," Snead said.

Back to Top

3. What services should be included in a furnace tune-up?

"A thorough furnace tune-up should include checking the burners, blower and motor, controls and chimney," said Doug Walter, president of Kansas Building Science Institute, Manhattan.

"In the burner assembly, the heat exchanger should be inspected visually for soot, corrosion and cracks," he said. If there is any concern about a cracked heat exchanger, additional tests should performed to verify that it is safe.

The burners should be removed and cleaned and the air/fuel mixture adjusted if necessary.

The temperature rise through the furnace should be measured to make sure it is within acceptable limits. Excessive heat rise indicates insufficient air flow, which wastes energy and may result in poor distribution of heated air.

"The blower motor should be lubricated if it is designed for lubrication," he said. "The blower should be removed and cleaned by brushing. "If your blower is belt-driven, you should check the belt for proper tension and replace it if it is cracked."

You should inspect your furnace’s filter and replace it if necessary.

Controls include the fan switch high-limit safety cutout and the thermostat.

"The fan switch should be adjusted to turn the blower on and off at the proper temperatures and the high-limit switch should be checked to make sure it will shut off the gas valve should the furnace overheat," Walter said.

"Mercury thermostats should be checked for level installation," he said. "The anticipator should be checked and adjusted if necessary for proper burner run time."

Check your flue for proper draft and inspect it for corrosion or leaks.

After inspecting, cleaning and reassembling the furnace, you should run it through an entire cycle to verify proper operation. With the burners and blower running, check the draft hood for spillage using a visual indicator such as smoke. You should test the burner exhaust ports for the presence of carbon monoxide using a CO (carbon monoxide) detector. Finally, turn on all exhaust fans in the house, including the clothes dryer, and check the furnace vent for adequate draft.

Back to Top

4. The new compact fluorescent bulbs that can be installed in incandescent fixtures look like a good way to save energy, but they are expensive. Are they cost-effective?

"Yes, fluorescent lamps are four times as efficient as incandescent lamps," said Doug Walter, president of Kansas Building Sciences Institute, Manhattan. "And, fluorescent lamps last nearly 10 times longer than incandescent lamps. Therefore, both longer life and increased efficiency contribute to their cost-effectiveness."

Throughout its 10,000-hour life, a 15-watt compact fluorescent lamp will consume $11 in electricity, at 7.5 cents per kilowatt hour. The lamp itself may cost $15, for a total life cycle cost of $26.

A 60-watt incandescent lamp would produce approximately the same amount of light, but would have to be replaced at least 10 times during the fluorescent lamp's life. The energy cost over the 10,000 hours would be $45 for the incandescent lamps, and the cost of the 10 bulbs would be about $5, for a total of $50.

So, despite its higher initial cost, whenever you replace an incandescent lamp with a compact fluorescent lamp, you will save $24 before you have to replace it again.

"From an investment perspective, the extra $10 you spend on the compact fluorescent will earn a 35 percent return each year over the four-year life of the compact fluorescent," Walter said. "And that's tax-free."

Back to Top

5. "I'm going to have my walls insulated. Are there any options to the plastic plugs that are used to fill the holes?

"Yes, you have options," Gene Meyer, extension mechanical engineer at Kansas State University. "Your best option involves removing a row of the siding and drilling the holes only through the sheathing."

Meyer noted an additional advantage to removing siding first — the drilled holes can be larger, allowing for tube-filling the wall. Tube-filling is a process where a plastic tube is inserted in the wall and the cellulose is blown further in the wall cavity. With tube-filled insulation, you get a more consistent job and higher density insulation, which helps slow air infiltration

A second approach is to drill through the siding and then use wooden plugs. To prevent the splintering of the siding, use sharp drills. If necessary, apply an exterior layer of spackling so the plugs are not visible through a coat of paint.

Back to Top

6. What should I do to close up a whole house fan for the winter?

"Because the hinged shutters in most whole house fans do not provide an effective air seal or appropriate R-value of insulation, it is necessary to take additional measures to reduce heat loss," said Bruce Snead, extension specialist in residential energy at Kansas State University.

There are three approaches to sealing up a whole house fan for the heating season.

You can mount a weather-stripped, insulating panel to the ceiling trim around the shutters with screws or hooks. You can construct this of a wood frame with several inches of foam insulation and gasket-type of weather-stripping attached around the edge.

"This is probably the simplest approach because it is installed inside the house, but it will also be visible," Snead said.

A second approach is to build an insulated and weather-stripped box that fits over the fan and seals down onto the wood frame around the fan housing.

"This box probably will require a greater depth, and it may be more difficult to achieve a tight air seal," Snead said.

this approach can be advantageous because the box is not visible from inside, and it can be left in the attic during the summer.

A third method is to drape fiberglass batts over the fan in the attic and use plastic or heat-shrink film to seal over the louvers from below. Reusable plastic kits for this purpose are available at discount and hardware stores.

| Back to Top |

7. What is the cost of operating a home computer system?

"At the average Kansas electric rate of 7.9 cents per kilowatt hour (kwh), a personal home computer system consisting of processor, video display monitor and printer will cost about 1.2 cents per hour of operation," said Doug Walter, president of Kansas Building Science Institute, Manhattan.

The energy use of each of the components per hour is: processor, 30 watts; video monitor, 45 watts; and printer, 75 watts.

Actual energy use will vary with the make and model of computer.

"A home computer system used eight hours a day, five days a week, would cost $2.11 a month to operate at 7.9 cents per kwh," Walter said.

When buying a new computer system or component, look for the Energy Star logo, which indicates that energy-saving features have been incorporated into the design of the system or component.

| Back to Top | Home |

Ask Energenie is produced by the Kansas Energy Extension Service through Kansas State University. This material was prepared with the support of the U.S. Department of Energy (DOE) Grant No. DE-FG47-92-CE60210. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the author(s) and do not necessarily reflect the view of DOE.