Q I want to use a stocking with salt in it to melt the ice dam on my roof. But where do I put this contraption?

A Do not put salt on your roof! Sodium chloride, or rock salt, is highly corrosive. It will damage the roofing, siding, gutters and downspouts, and the poisonous runoff will kill foundation plants and more.

If you are going to try any homemade approach for breaking an ice dam, use deicer. This method does work, I'm told. It breaks the ice dam, which allows water backed up behind it to drain.

Fill old pantyhose with deicer. (Calcium chloride and corn-based formulas are preferred, but they still may damage your home and lawn.) Place them on the ice dam vertically (perpendicular to the roof's edge) to create the drainage channels.

Frozen garage door Q Our garage door froze to the concrete floor. What can we do to prevent this?

A If there's no drainage problem, apply a liberal coating of petroleum jelly to the bottom gasket or weatherstrip. If there's a drainage problem (water collects or pools under the door), you'll have to fix that before you can solve the freezing-door problem.

Depending on the cause, you can raise the area with concrete coatings (make sure the door will still fit), or grind the apron in front of the door. In either case, it's a job for warmer weather, and you'll probably want to consult a concrete contractor. In the meantime, try to keep the area dry by sweeping or pushing the water from under the door.

Send your questions to Fixit in care of the Star Tribune, 425 Portland Av., Minneapolis, MN 55488, or call 612-673-7032, or e-mail fixit@startribune.com. Sorry, Fixit cannot supply individual replies.