weather-board

from The Century Dictionary.

• To nail boards upon, as a roof or wall, lapping one over another, in order to turn off rain, snow, etc.
• noun Nautical:
• noun That side of a ship which is toward the wind; the windward side.
• noun A piece of plank placed in a ship's port when she is laid up in ordinary, inclined so as to turn off rain without preventing the circulation of air.
• noun A board used in weather-boarding.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb (Arch.) To nail boards upon so as to lap one over another, in order to exclude rain, snow, etc.