The phrase "old barn" refers to a building that is no longer new, usually made of wood, used for storing hay, animals, or farming equipment on a farm. Full definition
I made one similar for my sisters new house where she used a ton of old barn wood from a family property which began as a dairy farm. (grandmashousediy.com)
What makes this one so unique is that it incorporates old barn doors. (morningchores.com)
I also made some great whale cut - outs out of old barn wood. (itsoverflowing.com)