Check local building code to see if you can attach a patio roof directly to your deck.
How to build a simple deck roof.
I show you the difference between a flush beam and a dropped beam how.
The simplest method and one that would work well against a two story house is a lean to type of roof.
Frame up a box the size of the outer dimensions of your deck using 2 by 4 inch lumber.
Step 1 build the frame of the roof on the ground.
The footings for porch decks must be larger than deck footings.
This video will show you every step you need to take to build a deck in a day or two.
Building on an existing deck.
Blow out the dust fill the hole with epoxy and insert the rod to the required depth.
Then run joists connecting the front of your roof with the rear every two feet along the length of your roof.
Many porches use 22 diameter corner and intermediate.
Building a shed roof over a deck.
Let the epoxy set leaving it overnight will assure that it is rock solid and then add the anchor bolt anchor washer and nut and tighten.
Install post base connectors.
Simply put a couple of posts in the corners of the deck farthest from the building with a header between them and add rafters up to the roof of the building or attached to a ledger fastened to the wall of the building.
For a solid connection you ll have to make sure the frame has the appropriate blocking.
These are used to attach the support posts to the frame of the deck.
Do not attach the post base to only decking.
Typical decks are designed to support 55 psf lbs per square foot.
As a result most decks have inadequate footings to support a new porch roof.
Make sure the frame has the appropriate blocking to ensure a solid connection.