There's an overflow pipe in what looks like an isolated position - what is it coming from?
The render is cracked in a number of places, significantly at the vertical join line with the new extension.
The render, to be blunt, has problems in patches & looks terrible.
Once you get blown and cracked render then water will enter behind it, and disfigure & destroy it within a few years.
Your render and external drainage would not pass even a mortgage survey without comment.
Water from above (perhaps a failed wet verge?) has cascaded down the render, staining past the overflow pipe.
Bellcast's should have been fitted above all rendered window or door openings.
And a Bell cast, or at least a Stop Bead, fitted above the String Course (the line of exposed bricks).
Why the Hopper in the down pipe drops? Plus, the pipe clips look shaky?
A photo showing where the Soil and rainwater pipes meet the ground might help a bit further?