One of my bedroom walls in my bungalow has a long wavy thin crack that goes from the top corner to the bottom corner. There is a similar crack on the outside pebbledash. I recently had new wiring put in when I changed internet provider so not sure if this is the reason for the crack or if it's totally unrelated. It's a room that is not normally used and the first indication of a problem was a smell of damp. I ran my hand along the wall and it was quite wet so clearly rain had been getting in.
What sort of workman would I need to employ to sort this out? Thanks.