Garage extension, where to cut existing soffit boards and fascia?

[nuzuki]

I'm one course below the soffit boards now on my garage extension. Just wondering how much is a safe bet to cut out either side of the brickwork? How's best to do this? I was thinking multi tool or jigsaw. I've not done this or seen this done before so just looking for some pointers.
Garage is protruding 3m out from existing garage. I've attached a picture to show the situation.
Thankyou

 

[Ivor Windybottom]

It depends on what your new roof is going to be, and what will be along that edge. Will you have matching soffit and fascia? Then you'd need a mitred joint on the soffit and a corner fitting on the fascia. If so then cut off flush with the face of the new brickwork for now, ready for trimming later.

Otherwise, it depends on what you're actually building!

 

[nuzuki]

Thanks for the reply Ivor

It's an apex roof not flat roof. Yes matching soffit board and fascia. How would you suggest I trim it? I got a feeling that old pvc fascia will be brittle after 50yrs of being in the sun

 

[Ivor Windybottom]

As I say, just cut flush with the face of your new wall for now. Then do whatever trimming's needed when you fit the matching new fascia and soffit.

I'd use an oscillating multi-tool. But if it's just plastic you may be able to get away with a Stanley Knife. Just use repeated light cuts, don't try to get through in one go.

But it may be plastic cladding over wood. If so then the multi-tool is probably the only way. You'll wonder how you ever managed without one once you buy one, they can do things that are otherwise impossible.

It doesn't matter about the pointing it will be covering, as all this will be covered anyway.

Check for asbestos soffits first - if so then everything changes.

 

[Ivor Windybottom]

It does look like cladding from your second photo, I just saw the nail heads. So forget the Stanley knife idea.

 

[nuzuki]

Thanks Ivor. Yes those multi tools are great tools. Off topic but I think they caused a fire at St Paul's Cathedral or similar a while ago.
Yes you are correct it's those white plastic headed nails. The boards look like wood covered in a white plastic fascia

 

[Ivor Windybottom]

They can smoke, especially if labouring in one spot, best to move it around. I'm guessing the cathedral probably involved some very solid old hardwood.

Just check that soffit is wood. 1960s bungalows sometimes used asbestos panels.