Seal the garage door at the bottom before screeding

Hello everyone,

our garage door at the back is now installed. The window installer participated, although EL. He sealed it professionally on the sides and top. Since screed will still be added to the garage, there is currently a gap under the door. It has to be at screed height. The window installer has occasionally placed a few wooden blocks underneath so that the door does not just "hang" for now. Today on the construction site, I was asked how the sealing at the bottom works before the screed. I assumed that the screed would be laid and then sealed on the screed. Hmm, he said it must also be sealed with such a tape before the screed. But how do I do that best when there is no floor below yet? Where and how should I seal it?

You have to foam the joint, and then there is a so-called EMPD BAND, with this band you have to seal your joint, or you go to the specialty store and get advice there again

By "unten am Boden" he means the concrete floor, so you have to install an EPDM STRIP (sorry, I wrote it wrong above) between the concrete floor and the door rail.

I understand about the tape. They also left something like that for me at the construction site. But the gap is about 10cm. Tape will be difficult there.

That's what I'm getting at. I thought they would extend the screed up to under the door and that way the intermediate gap would disappear. But somehow that doesn't seem to be the case. Or rather, I also have to seal before the screed. But how with such a large gap?

Actually, it is like this that the door installer has to ask for the height of the top edge of the screed so that the lower door finishing rail is flush with the screed. Maybe a photo of the door?

Currently no photo available. I will be on site again tomorrow and can provide it then.