Advice re Blue tits nesting near extraction fan

Good evening all, I'm new here and my concern is about some blue tits nesting within the wall cavities of a maisonette. They have accessed it through a half brick missing. However my concern is for them as within a meter on the external wall is a kebab shop extraction fan witch is extremely noisy and drops fat and grease from the top. This is also producing lots of noise and vibration. This fan is on 12hrs a day 7days a week. 

Any help or advice here would be appreciated. I know its against the law to move them whilst nesting etc however it's their actual welfare I'm thinking of. 

  1. Thanks everyone