A gambrel roof on an old building.
gambrel roof definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a roof with two slopes on each of its two sides, the lower steeper than the upper
gambrel roof definition by American Heritage Dictionary
A two-sided roof with a double slope on each side, the lower slope having the steeper pitch.