Brickwork staining - does this look like a problem with mortar or an internal leak? All manner of questions and solutions to problems and issues surrounding the subject of brickwork, blockwork and stonework

[bexxr]

I've noticed this brickwork staining on the outside of our house - underneath the upstairs main bedroom. This photo has been taken today.

The white stuff on the bricks has always been there, but looking at older photos, it is now more/has grown compared to a couple of years ago.

Here is a closer image. There is a radiator under the window in the bedroom, but there is no staining or water ingress on the interior, and when measuring it seems the middle of the staining isn't where the heating pipes are (they are in the floor of the bedroom.

Does anyone have any idea what could be causing this, but more importantly what type of tradesperson/expert we need to instruct to come take a look please?

Getting a bit worried that there is a leak. But hoping it's just failed mortar that can be replaced?

Also, it rained last night.

Many thanks

[stoneyboy]

Hi bexxr,
It looks very much as though there is water run off from the window, probably there are internal drainage holes in the frame down into the cill. If you put a level on the cill you will probably find it is down very slightly on the left end.
Regards S