There's currently no dedicated roof blocks. There's not even any in other mods, at least not without an OP tech/magic mod attached to it.
As is such the reason for my suggestions: Roof Tiles in various styles and colors.

Below are a few example textures I threw together. They're not really the right style, but they're what I came up with.

They are very bright, but I would like to see some more classic and medieval type stuff

I have been working on this since I saw your request on curseforge @VermillionX :)

I like the third and fourth textures as well as the last one.

Are all these 16x?

Yes, they are 16x.
I did a bunch of other ones but they weren't as "normal" (Thatch as well). (3 other below)



I also noticed that there are (seemingly unused) Roof Shingle textures already in chisel.
EDIT:
Here's a remake of those roof tiles in vanilla style: