Is caulking the ends necessary?

When installing tongue and groove siding, many homeowners wonder how to approach the edges of each board. Rather than caulking, many contractors suggest installing a joint flashing behind each tongue and groove joint. This intercepts and redirects the flow of water away from the building.

Furthermore, water should exit through the bottom of each board. While paint may stick the boards together, caulking the boards can lead to water buildup and damage.