No, it goes in now. It needs to be the entire thickness of the deck. If the deck goes below the bond beam then you need to dig down until you find the bottom of the deck and start the expansion joint there.Expansion joint goes in after they lay the mortar bed and before they lay the coping, yes?
You don't even have an expansion joint then. The deck will expand and push on the mortar bed which will crack it right at the joint between the old and new.Thanks @bdavis466 ... I should have asked that question yesterday as it appears that ship has sailed.
I just told them to put it in on top of the mortar bed (they just laid it) and in between the coping. I guess the mortar bed will be dry in a couple of days. At least they are going to finish it off with Deck O Seal... Hopefully it's better than no expansion joint at all.
That only works if the coping is the same thickness as the deck. Since yours is not, guess what it's going to take the force of the deck movement...Ugghhh, I just tried to talk to the guy and he said it never goes in on the mortar bed... always before the coping. Says that's how he always does it. Great, just what I need... get in an argument with the contractor.
Btw, there's definitely a bit of a language barrier as he only speaks Spanish and I barely understand Spanish... so one of his guys are translating.
I need to order a case of Bluetooth Babel Fishes for everyone....Google translate built my rear deck and stairs. Polish only guy would speak and google would tell Spanish only helper. And vice versa. It was fascinating to watch.