When does MDF offgas? When the heat is on in the winter or throughout all seasons?

— Rachel Mitchell Rutland, MA

Answered by David Bergman on July 13, 2010

Are old appliances green because we are reusing, or not green because they are not Energy Star?

— Chris Tissot, North Hollywood, CA

Answered by David Bergman on October 2, 2007

Tankless water heaters: electric or gas?

— Michelle Allman, North Hollywood, CA

Answered by David Bergman on October 2, 2007