Deck Footings and Deck Posts

How deep should deck footings be?

What size deck posts should be used on a deck?

The answers vary depending on several variables. Here are some of the things that may be addressed on a deck inspection. Some of the items may not be accessible at the time of inspection.

• Deck footings must be at least 12″ below the undisturbed soil surface.
• Size and thickness of the footings are determined by the tributary area that they support, and the load bearing value of the soil.
• Where decks are attached to a frost protected structure, the footings must extend below the frost line, be erected on solid rock, or use other approved methods of frost protection.
• Deck posts must be centered on the footings.
• Maximum height of the posts are determined by the size and species of the post and the tributary area.
• Lateral restraint must be provided where the posts bear on concrete footings.