How to bridge the gap in wall cavity after fitting new UPVC door + frame

[Some-Hope!]

Hi, I had question answered on how to fit door frame, can someone give me a solution to filling the cavity gap that will be left between the new door frame and the outside bricks opening.

As I am doing up the hallway too, will it be best to take the plaster off the internal wall and fit the new frame brick to brick and not plaster to plaster? (the current frame is fitted between plaster to plaster)

The frame will be fitted to internal opening and the frame will not butt up against the bricks on the outside skin.

Do I use cavity closer or expanding foam or neither.

many thanks Jimmy

[The Natural Philosopher]

I would first make sure the thing is solidly in place, then use foam, then cut it back and point up the outside with mortar, or use a frame sealant, and skim over the foam inside, and finally use decorators caulk to make a flexible fillet to paint to.