Why are bolt holes in wood structures sealed?

The sealing of bolt holes in wood structures is primarily aimed at preventing moisture entry and corrosion. Wood is a natural material that can absorb moisture from the environment, which can lead to deterioration over time, especially when combined with metal fasteners. If bolt holes are left unsealed, moisture can accumulate in these openings, leading to the potential for significant structural issues such as rot or weakening of the surrounding wood.

When moisture penetrates the bolt holes, it can also cause corrosion of the metal used in the bolts or nuts, which can compromise their integrity and ultimately affect the stability of the structure. By sealing the bolt holes, this moisture ingress is minimized, thereby extending the lifespan of both the wood and the metal components used in construction.

Improving aesthetics, facilitating easier assembly, or increasing bolt strength do not directly address the primary concern of moisture and corrosion, making them less relevant reasons for sealing bolt holes in wood structures. Therefore, the focus on preventing moisture entry and corrosion underscores the importance of this practice in maintaining the integrity and durability of wood in aviation and other applications.