Q - My bathroom vent fan sounds like a Boeing "747" preparing for takeoff. Although it isn't as efficient as a vent fan, I open the window instead. Are there any quieter and efficient methods to vent my bathroom? G.J.

A - It is very important to ventilate your bathroom, especially when showering or bathing. In an efficient airtight house, excessive moisture quickly builds up without adequate ventilation. This can deteriorate your house and cause mold growth and allergies. Opening a window wastes a lot of heated or cooled room air, plus you often forget to close it again.There are several new super-quiet designs of bathroom vent fans available. One design uses a powerful axial fan that mounts in your attic. It draws air through a typical small vent grill mounted in the bathroom ceiling. The other design uses a standard ceiling-mounted vent fan with a speciallydesigned super-quiet fan and motor.

The sound level of vent fans is rated in units called "sones." One sone of sound is about as loud as a new very-quiet refrigerator. For comparison, a sound level rating of six sones is twice as loud as three sones. The actual energy efficiency of the fan motor is similar for most models.

An attic-mounted axial fan is most quiet. Its sound rating is about 2.5 sones at the fan itself in the attic. However, in your bathroom, you just hear the squish of moving air. You can also use two ceiling air inlets, one over the shower and one over the sink, both connected to the same fan.

It is easy to install the axial vent fan in your attic. A 6-inch diameter fan is most common with an air-flow-rating of 270 cubic feet per minute (cfm). You just attach it with its mounting bracket anywhere in the attic. Then run 6-inch diameter flexible duct down to the ceiling air inlet grill. Run outlet duct from the top end of the fan.

New standard ceiling-mounted super-quiet bathroom vent fans are specially designed and constructed. These quiet fans (as low 1.5 sones) usually have slower motors and are better-balanced than standard vent fans. To further reduce the noise level, the motors are mounted in rubber bushings and bridge brackets are used to mount the motor out of the air stream.

Don't get a vent fan with too little air flow capacity for your bathroom. The fan should be able to quickly ventilate the bathroom. This minimizes moisture migration throughout your house and reduces overall energy consumption. Keep the door closed until the bathroom is clear. You may have to saw a half inch off the door bottom to allow for enough air intake.

You can write to me for UTILITY BILLS UPDATE No. 360 showing manufacturers, model numbers, sound levels, and air flow capacities (cfm) for attic-mounted and ceiling-mounted super-quiet bathroom vent fans, and recommended air flow capacities for various-size bathrooms. Write to James Dulley, The Deseret News, 6906 Royal Green Drive, Cincinnati, OH 45244. Please include $1 and a self-addressed STAMPED BUSINESS-SIZE envelope.

Q - We have been washing our clothes in cold water to save energy, but they just don't get as clean as in hot water. Do you have any hints to help us get better results with cold water washing? T.T.

A - Many detergents don't dissolve well in cold water. First dissolve the detergent in a small quantity of hot water to make a paste. You can also use some of this paste to pretreat badly soiled spots.

Often, you'll have to use a little more detergent with cold water. If you can control the cycle on your washer, let it agitate a little longer. As a last resort, use a hot water wash every other time. At least you'll save half of the energy to heat the water.