Wooden garden house: roofing felt instead of wall barrier membrane?

I have a log cabin garden house that I would like to set up spontaneously tomorrow. The foundation consists of terrace slabs and I do not want to lay an extra floor, so I want to place it directly on top. Now I have read that in such a case you should lay a wall barrier and place the first beams on it. Meanwhile, the hardware store is closed. Can I also use roofing felt? Is that equally suitable?

For a garden house, that works, it's basically the same in the end.

Great, thank you very much for the quick response.

The wall barrier is now slightly thicker than the wall, and when it rains on it, water actually stands on the barrier and can especially soak into the wood. My plan is to fold the barrier once and staple it to the house, and cover the edge with silicone. So something like in the side section (right is outside):

[ATTACH alt="mauersperrbahn.png" type="full"]44736[/ATTACH]
Does that make sense?
Is there anything else to consider that is often done wrong with garden houses or not thought of the first time?

In the resulting space, moisture may accumulate. Also, the thin cardboard quickly tears under low mechanical stress. I would rather install a drip edge there.

Google cove.
Your idea, as says, rather makes it worse.