Frame up slanted roof

[eddiw]

I'm planning to frame an old slanted ceiling and install a wooden interior panel instead. (It's Moelven's interior panel by the way). The studs I plan to use are 45x45. The slanted ceiling currently has tongue and groove boards under a 3mm board covering the slanted ceiling. I'm thinking of framing with c/c 60. A potential problem is that I don't think I'll hit the ceiling joists if I frame with c/c 60. Will it hold if I set up the studs as planned, i.e., only in the tongue and groove boards which are in turn attached to the joists? Since the board is over the tongue and groove planks, it's also not entirely easy to find the joists. I've managed to find and mark a few, but not all. Should I perhaps attach to a ceiling joist and ignore the c/c measurements? It will be what it will be in that case.

How would you have done it? What is customary? The house is from the 1940s, and considering how the knee wall (which we took down) was attached, I guess the tongue and groove boards in the slanted ceiling are attached with large nails.

I have started the framing, but got a bit unsure, so I thought I'd ask here before continuing. How many screws should be used to attach the new studs to ensure it stays in place? The slanted ceiling is 195 cm.

Thanks in advance.

 

[Pappa1986]

I am planning to frame an old slanted roof and install a wooden interior panel instead. (Moelven's interior panel, by the way)
The studs I'm planning to use are 45x45.
The slanted roof currently has tongue and groove boards under a 3mm board that covers the slanted roof.
I was thinking of framing with c/c 60. A potential problem is that I don't think I'll hit the roof studs if I frame with c/c 60.
Will it hold if I install the studs as planned, i.e., only in the tongue and groove boards which are in turn attached to the studs? Since there is a board over the tongue and groove planks, it is also not easy to find the studs.
I have managed to find and mark some, but not all.
Should I perhaps attach to some roof studs and ignore the c/c measurements? It will be what it will be in that case?

How would you have done it? What is customary?
The house is from the '40s and considering how the attic wall (which we have taken down) was fastened, I guess the tongue and groove boards in the slanted roof are attached with substantial nails.

I have started the framing, but became somewhat doubtful so I thought I'd ask here before continuing.
How many screws should be used to attach the new studs to ensure they stay in place?
The slanted roof is 195 cm.

Thanks in advance.

If you attach the studs to the tongue and groove boards, that should be sufficient.
You don't need to locate the roof studs.

 

[eddiw]

If you attach the studs to the tongue-and-groove boards, that's sufficient.
You don't need to locate the ceiling joists

Ok that's good. If I'm lucky, I might hit a ceiling joist.
How many screws should you use to secure the studs, approximately?
3-4?

 

[Pappa1986]

Ok so good. If I'm lucky, I might hit a roof rule.
How many screws should be used to fasten the rules, like?
3-4?

Yes, 3 are enough.