What is the maximum height for a 4x4 wood deck support post?

The maximum height for a 4x4 wood deck support post is indeed 8 feet. This standard is based on building codes and structural engineering principles that take into account the stability and strength of wood as a material. When a post exceeds this height, the risk of buckling under load increases significantly due to the slenderness ratio and the way the post bears weight.

At 8 feet, a 4x4 post is typically strong enough to support the loads imposed by the deck and resist lateral forces, such as wind. If the post were to be longer than this, a larger dimension or additional support methods would be necessary to ensure safety and compliance with local codes. Hence, keeping the height to a maximum of 8 feet helps maintain structural integrity and safety for the deck.