We need to find a nontoxic concrete sealer. We have a child with respiratory problems.

— Susan Blumberg Scarsdale, NY

Answered by Elizabeth DiSalvo on December 22, 2010

The attic in our 2004 house has no insulation. Will spray foam irritate my asthma?

— Marie Richmond Hill, GA

Answered by Danny Kelly on December 2, 2010

How do I install an exhaust fan in the garage to activate with the garage door?

— Josh Hallgren Pullman, MI

Answered by Raymond Pruban on November 25, 2010