Hi - am new to doityourself and have a question about building a proposed deck. Im attempting to design a deck that has about 9" of working height from the lip of the door that will open on to it, meaning Im stuck using 2x6 joists under 5/4 planking. 2 sides of the rectangular 20 x 14 ft deck will be anchored to the house.

My question is this: the deck will be covering an ancient mortared-in-place brick patio. Since the brick patio has been there forever, and has not broken up or cracked (I live in NY State, where footers must go down 48"), I assume that it must be installed adequetly (not heaving), meaning I that I should be able to place short 4x4 posts directly on it for supporting the deck. Is there anything wrong with this rational? If not, I will be tasked with drilling A LOT of 48" holes in the ground..

Please tell me you like my thinking!!

Dave in NY

 

You're thinking is correct. It's too bad that it doesn't match the code. You still have to install the correct footings as if the patio didn't exist. Some of my jobs are correcting that exact scenario. I just did one in the early spring. I'm in NY as well.

 

Not in NY but in my local if not attached to house then deck blocks can be used for low decks, maybe same in your area with the old deck being your deck block.

 

If it is attached to the home, the deck must be supported by a foundation (usually piers or Sonotubes) that are below the frost line to avoid differential settling and heaving or damage to the house or deck. If not attached, you can get away with whatever the code allows and just be willing to live with the results.

If it is attached on two sides, you certainly do not want the outer portion to heave upward every winter and possibly not go back down.

Dick