I have a large concrete patio at the rear of our house - 12 inches thick, with no settlement noticed (it's been down for about 7 years now).
We're considering extending our deck out; at the moment we have a simple 5x5' deck which just leads to a set of steps down to the patio. We want to now build a 12x22' deck, and extend the roof out over the new deck.
Question; For the deck footings, do I need to cut through the patio and dig to below the frost level (~36inches in Utah), and then build back up with concrete footings, or can I just attach the 6x6" support pillars of the deck direct to the patio?