It’s nice to have a view. This fellow’s deck was beginning to deteriorate, with unprotected wood splitting and cracking, and in some places showing dry rot deterioration. The deck was built by a previous homeowner, and most like was done without a permit. It sits on sleepers laid directly on top of a torch-down roof.
His desire is make it like new, and he wants to rebuild it, but using a better support system, using new support beams with loads traced down through the structure below. I pointed out that he could do that only if he raised the deck, which would make it higher than the sill of the door leading onto the deck. Water problems would ensue, almost certainly.
He had some record plans, from which I examined the roof framing, and found it to be adequate to support the deck loads as built. After looking at costs for the options I provided, he decided to simply repair the deteriorated wood on the existing deck. He saved a bundle in my estimate – that new design would have been fun, but messy and expensive.