Q Our church wants to floodlight the parking lot. Is it true that sodium-vapor lights are less expensive to operate and last longer than mercury vapor? Also, what should be the proper height of the poles? M. Langley Sarver
Sun City, Calif.
The efficiency of lamps is measured by the amount of light put out in lumens per watt of energy. Mercury-vapor lamps produce 56 lumina per watt.
High-pressure sodium lamps put out 102 lumina per watt and give off a pinkish light, while low-pressure sodium lamps produce 128 lumina per watt and give off a yellowish light. Metal halide lamps produce slightly less than the high-pressure sodium lights, and their light is close to the look of an incandescent bulb. Mercury-vapor lamps are rated as lasting 24,000 hours, compared with 18,000 hours for low-pressure sodium lamps.
To determine the pole height, seek the help of an electrical engineer or experienced electrician, as there are many variables that need careful consideration.
Q We expect to remodel our home and would like your thoughts on the correct height of wainscoting. I've heard that it should be to the bottom of the windows, but our windows start about 18 inches above the floor. Will the windows have to be raised?
A Connecticut reader
The height of wainscoting as used for decorative purposes is generally related to the proportions of the room. If the ceilings are around 8 feet high, I suggest that the wainscoting be about 30 inches high (this is chair-rail height). It's all right for the windows to project into the wainscoting so long as they are sensitively trimmed out around the entire window with wood that matches the chair rail or your paneling. Spend some time looking through magazines to see how others have done it.
Q We are getting a bad odor from our shower drain whenever we run the water down it. A lye treatment helps out, but after a few days the odor is back again. Any ideas? Also, in the winter the outside of the toilet tank sweats, as well as the sliding-glass door. We heat with a potbelly stove. Is there a way to stop the troublesome condensation? Last question: Our bathtub leaks around the drain and we can't get any caulking between the drain flange and the tub. What can we do short of buying a ne w tub?
Mrs. Diana J. Usrey
Sewer gas is getting up through the drain because it is not venting properly. You'll have to either run a ``snake'' or water from a garden hose down the vent pipe on the top of your home. The water pressure or snake should loosen the soap-film blockage. Be careful not to use lye too often, as it can, over a period of time, eat out the bottom of the plumbing trap.
The sweating is due to very high humidity inside your house. One of the byproducts of combustion is water. Thus, the problem can be attributed in part to the stove you are using. Either use a dehumidifier, or else bring a little more outside air into the house. Either way, the problem should be reduced.
Plumbers have special wrenches for removing the tub drain and replacing the washer under the flange. While it's a simple operation, it does take a little extra ``muscle.'' To the real estate editor:
You published a question from a person looking for stock plans with which to build a small passive-solar house. I recommend that Claire Cottrell check the February through April 1978 issues of Better Homes & Gardens magazine. There are three passive solar homes described and the magazine has available stock plans for each. My wife and I built our home from plans in the February 1978 issue and have been very happy with the result.
George R. Schultz
The Ask an Architect column is now called Home Fix-up. If you have a question about designing, improving, or maintaining your home, school, church, or place of business, send it to the real estate editor, The Christian Science Monitor, One Norway Street, Boston, Mass. 02115.