Human activities aren't the only things that move indoors in the winter. Pests and moisture problems also take advantage of the season to appear inside our houses, where the welcome is less than gracious.
Recent letters from readers remind us it's the season to be bothered. A reader in Baltimore has a pestiferous problem: recurrent spiders.
"We moved into an older house," she writes, "one that had been vacant for about 8 months. Spider webs formed everywhere! We figured after we lived here and cleaned regularly, they would go away. Not so. We've been here 1 1/2 years and we still see lots of spiders -- large and small -- and find webs growing on furniture legs, in corners, etc. Is there something we can do, besides using lots of chemicals, to rid ourselves of this problem?"
As is usually the case with a persistent problem, there's no immediately satisfactory answer. It turns out that spiders are not stupid -- they know a warm environment is nicer than a cold one, and when the weather begins changing in the fall, enterprising arachnids who have been living happily in the garden start looking for warmer quarters.
"Spiders are always worse in the fall," says Harriet Tinker, a horticultural consultant with the Baltimore County office of the University of Maryland Cooperative Extension Service. "You can't keep them out."
Spiders lay eggs in August and September, and if you've got a houseful of spiders, they're going to be hatching in the warmth.
Worse, Ms. Tinker notes, spiders are not technically insects, so insecticides don't work, unless you can give each beastie a Terminator-like direct hit.
There is one encouraging point: Once the weather turns cold, spiders stay put. The ones outside will be hibernating, so you will only have to deal with the population you already have indoors.
Continue to clean out the webs, Ms. Tinker says. If you figure out where they're getting into the house -- a crack around the foundation, or loose siding, perhaps -- you might be able to seal that and prevent new spiders from taking up residence in the spring.
And you might think about a little spider co-existence. The webs are ugly and sometimes spiders bite, but they're not all bad creatures. They eat a lot of less desirable insects -- flies and mosquitoes. Of course, that's only in the summer.
Another reader in Bel Air has a problem with moisture in a bathroom that has led to ceiling mildew.
"Two years ago I moved into a condo," he writes. "I installed a shower door. However, when we shower, we leave the bathroom door open for ventilation. I recently installed a new 90 cubic feet [per minute] fan, which is more powerful than the old one. The black spots on the ceiling will have to be removed and painted. What shall I do to remove these stains and how should I paint the ceiling, and what else should I do to correct the problem?"
The first step, according to Larry Horton, general manager of Baltimore Budeke's paints, is to kill the mildew. "If you don't, it will continue to grow under the new paint."
Mr. Horton says, "Use a quart of bleach and 3 to 4 ounces of trisodium phosphate to a gallon of water." (Trisodium phosphate, or TSP, can generally be found at hardware and paint stores.) There are expensive solutions designed to remove mildew, Mr. Horton says, but this formula is simple and inexpensive. Apply the solution with a sponge and rinse well with clean water, he says.
When the surface is dry, Mr. Horton says, it should be painted with a new type of paint designed just for kitchens and baths, which contains a mildecide. (Coronado and Zinsser are two good brands, he says.)
It's also important to use the ventilation available, Mr. Horton says.
We'd recommend, in addition to leaving the door open, running the fan during the shower and afterward for 10 to 15 minutes, or until the bathroom walls are dry. It may even be a good idea to dry off the walls after a shower.
One culprit in this problem may be the shower door, which has a tendency to direct moisture upward in a manner far more pronounced than with a curtain. Unless the bath was designed with enough ventilation to accommodate a shower enclosure, the door may cause more problems than it's worth.
Finally, when we wrote recently about new products we liked at the National Association of Home Builders recent Remodelers' Show exposition in Baltimore, we got a lot of calls and letters asking where to find the Screen Tight Porch Screening System, which uses vinyl channels to hold screening in place. For inquiries, call (800) 768-7325 to locate a supplier near you. Or write to Screen Tight, 221 N. Fraser, Georgetown, S.C. 29440.