(pronounced FER-ing strihps)
“Furring out” means setting off a new wall in front of one that is already built. If you have little space available, do not need to create a very deep dead air space between the old surface and the new, or just need to even out the existing uneven wall, you can use thin furring strips. These strips of either wood or metal attach to the existing surface, and then you attach the new surface of sheetrock, paneling, etc. to the furring strips to create a nice, level surface.
See also: furr out