How to best mend these cracks in Victorian Bay Window?

[Dave0101]

How would I best mend these cracks in the bay window area?

Looks like I would have to first remove all the old render/cement/filler/silicone. It seems when they tore out the old original wooden windows they cracked a lot of the render/stone and then patched it up and in time it came loose hence the crack. I estimate these PVC windows were fitted around 2005.

However how should I fill it back up most effectively before painting it?

 

[blup]

Some sort of cement based filler like bosch cementone, available for SF and toolstation, they can be overpainted iirc.

Blup

 

[Dave0101]

Some sort of cement based filler like bosch cementone, available for SF and toolstation, they can be overpainted iirc.

Blup

Would it be correct to first pick out all of the old cement/filler/silicone between the crack and the window before putting a new cement based filler into it?

Also once it's done I think it will need new silicone all around right?

 

[HERTS P&D]

Are you a tradesman or diyer? as it looks like there is scaffolding up and the front of the building is being decorated.

Andy

 

[Dave0101]

Are you a tradesman or diyer? as it looks like there is scaffolding up and the front of the building is being decorated.

Andy

DIYer,

Scaffolding is up for re-roofing which is being done by a Roofing company.

I want to deal with the windows myself

 

[blup]

Would it be correct to first pick out all of the old cement/filler/silicone between the crack and the window before putting a new cement based filler into it?

Also once it's done I think it will need new silicone all around right?

Yes, and a suitable exterior silicone.

Blup