We have a preexisting deck above where we want to put a stone/concrete patio below. The existing footing are differing heights and in general are lower (6-12") lower then where we'd like the patio to be at. This leaves us needing to make adjustments to the deck post that will eventually have to be replaced (20+ years hopefully). What is the best way to build the patio to not prematurely rot out these posts? Better to use pavers then concrete? Should we do pavers so redoing the post in years to come won't involve busting up concrete? or would using pavers just rot the wood out sooner since there would be more water retained in the area? Is there something I could wrap the posts with that would protect them? More importantly, is there a cost effective approach?

I have just an aluminum patio cover & it has 4 posts bolted into the cement, I think it is 20 ft long. They are metal tho. I reinforced it couple of years ago as we are getting much stronger winds than we used to get. Doesn't sound like enough to me. But I'm not in construction, just helped my dad build our houses from time I was young. 1 good wind & you will have a twisted mess in my book. Much easier to add a post or 2 (at end of house where connected to house- never heard of doing that before.) don't you have any rules on adding a roof or patio cover in your town. Out here the posts have to be attached to metal brackets put into cement-usually when patio is poured. Hope you don't have a teen on a power ride-on lawn mower, just 1 backing into that 1 post & trouble!!!! Or if car or truck can get near it. Accident waiting to happen!! So your 1 post fails, what do you think will happen? How wide is it? Mine is 10 ft., I think It is also attached to house on 2 sides bolted unto the stucco every few inches. I live in earthquake country, I've seen a lot of them twisted, & they are a mess & try removing it once it is twisted & tweaked, almost impossible.

Idea two sounds better as far as cosmetics. You wouldn't have to use lags,2-1/2" deck screws would suffice.Place two screws about every two feet,sinking the deck screws in slightly.Also put two screws either side of the splice.

I don't understand where your question is going. "Well, I am not suggesting that the old wooden siding is all dry rot, just in some spots. And, besides, there fresh new wood will be installed to give a uniform "nailing" system of rails." OK if you're replacing rotten wood then you're not going to cover it. "My concern is that a house that has nice new siding on it may have a lot of rotten wood underneath, and if it is at least stable, I suppose it doesn't matter." If there is a lot of rotten wood under new siding then it probably isn't secured properly. This would matter. FWIW, before I bought an older house that had been vinyl-sided (and especially if I suspected rot under the siding) I would "unzip" a couple pieces in likely rot areas to check out the substrate. "And then there's the trim boards, which are almost always pine or fir and almost always have some rotten spots, which are just covered with an aluminum or other thin material." Agreed and localized rotted locations probably aren't a big deal except that the rot often occurs at the ends of the boards which need good material to nail the bent facia covering. Either the installer needs to do really good brake/sheet metal work or the boards beneath were replaced before covering. IMHO, putting new vinyl covering over old, deteriorated, siding is like putting a rug over a hole in the floor.