Fitting DG frames in a rendered apperture

[Goochie]

I have 4 windows to replace, two of them are in plain brick walls where I can easily measure the size required, the other two are in a rendered wall.

In this wall, the rendering goes into the reveal on the outtside.

I have looked at how next-door have had theirs fitted and it seems the installers have simply measured the size of the rendered apperture and (I presume) packed out the frame so that the rendering doesnt have to be removed.

However, I've read on some websites that you have to remove the rendering to fit new frames in such a wall.

 

[The-brickie]

If your measuring yourself you could make them fit inside the render but watch out for the inside reveals!

On rendered walls I measure internally and add 10mm to sit behind the render if feeling lazy, proper way is to hack off a bit of render (it will get damaged anyway) and find the brickwork and measure from that.