Q: Our seven-year-old finished garage, built on a slab has mold on the ceiling in all three bays. One can see the outline of the ceiling studs. The walls are clear. There is an apartment over the garage. Where should we start, please.

MARY COTTER-LEMOINE, New Hampshire

A: Before starting, an explanation, complicated by the apartment above the garage, is this: The garage ceiling is not insulated, and the ceiling joists (not studs) are a bit cooler than the whole ceiling, and water vapor builds up in the garage and condenses on the ceiling under the joists, and mold grows, hence the mold is only on the outline of the joists. To start, treat the mold stains with a mix of 1 part bleach and 3 parts water. If the ceiling is not insulated, have cellulose blown in. If the garage ceiling is already insulated, then ventilate the garage to release all that water vapor outside. Q: I recently took 3 wool shirts out of the closet for winter wear, and found moth holes in two of them. I washed and froze both of them to kill any eggs, and hung a "Safer" trap to catch any live moths. What else can I do? I really don't like the smell of mothballs.

FRED BROWN

A: Go to a store that sells anti-moth products, and you should be able to buy a non-odor treatment.

Keeping rodents out of car

A caller recently asked if there is a way to keep rodents from chewing electrical wires in his car. The car is parked outdoors, and he has no garage. The Handyman suggested he find a garage he could rent and make rodent proof, or install deterrents in the car.

Here is what Dick Shohet of Carlisle suggested: "We find that fabric softener sheets work wonders to discourage rodent damage in our vehicles. We put a sheet under the hood, in the trunk, and a third somewhere in the cockpit. Shazam! No rodents. And they smell nice."

Thanks, Dick. Your answer went right into my archives.

Q: Several months ago, you recommended a company that can inspect, consult, and/or remove mold or mildew in residential property. Would you please list that company again?

PETER, Harvard, Mass.

A: Yes, of course: May Indoor Air Investigations in Tyngsborough, 978-649-1055, www.mayindoorair.com

Q: We have a very long ranch that is over 50 years old. We have forced hot air heat/air conditioning through floor grates and overhead ducts. Every year the furnace is cleaned, I ask about cleaning the ducts. No one ever recommends it. But, I have not understood why. Please let me know the company you would suggest and how often.

WORRYING ABOUT THE DUST

A: You are due for duct cleaning, which is recommended every 10 years. Hire a duct cleaner, not a dime-a-dozen company that charges $10 a duct.

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