Gap between terrace and house wall with expanding foam tape?

Hello everyone,

I've been looking for a while now but somehow I can't find anything suitable.

The situation is that we have built a terrace onto our house. To avoid damaging the plaster and insulation, we decoupled the terrace from the house. The wall beam basically rests on posts that are about 6cm away from the house wall. Part of the terrace serves as a shed.
Now the question: In the shed, we would like to seal this 6cm gap. What do you use for something like this? Is there swelling tape in this thickness? Or any mats?

Many thanks in advance,
Jana

Fill up with gravel?

No, it's about the gap between the post and the wall. So vertically 2.50m upwards. Gravel would trickle out on the right and left from a certain height.

What should it be sealed for, because of water or -Luft&Staub-? A swelling tape could then actually be a simple and quick solution

Yes, Quellband was my first thought but with 6cm I don't know what I should use there. That's why I thought there must be something equivalent for such large openings.

well, why not screw a wooden slat or something similar in front?