A floating deck does not require footing installation. Instead, the deck floats on concrete blocks set on top of the ground. Concrete block manufacturers offer special blocks for supporting floating decks. These blocks often include metal inserts that support the posts of the deck.
The only excavation the deck requires is removing enough dirt to ensure the blocks are level. The installer usually removes the sod from the location of each block, packs the soil and adds gravel for drainage under the block. Therefore, floating decks are not appropriate in areas where high winds could lift them off the blocks.
The absence of the footing limits the size and height of the deck. Most building codes require installers to provide footings for decks attached to a house or over 30 inches tall. Decks over 100 square feet usually require footings. Most codes do not allow the builder to include any structures above the surface of the deck with a floating foundation.
Once the blocks are in place, deck construction is similar to building with a footing. Support beams connect the blocks, and the deck stringers rest on top of the beams. The installer adds decking material across the stringers, leaving space for drainage between the boards.