Deck footings are used to ensure the integrity of the construction as well as safety to anyone who may be on the deck at any given time. The deck footings are poured concrete that goes below the frost line so that it does not heave.
Reasons for Deck Footings
Building a deck over a concrete footing is done for a variety of reasons. They include drainage of water under the deck, keeping the timber away from the ground, stabilize the construction, and also to keep air flowing under the deck.
Decks without Footings
Building a large deck, that is attached to a house, should be built on deck footings. However, a small deck, that is a few inches off the ground, will be able to sit securely on concrete blocks. The block should be reinforced with some rebar through the center and Ready Mix Concrete.
Small Garden Decks
A floating deck that is built close to the ground will not need to have any kind of deck footing. You can use some small concrete blocks where you can lay planks into grooves that are already there, or a post that sets into a pre-formed hole.
Safety Rule for Deck Footings
For the most part, a deck footing must be used if the deck is going to be higher than your waist and/or larger than 100 square feet. The weight will need to be carried by the footings to ensure that the deck does not fall, tip, or rot away after only a few years.