flys lots of them

[cris r]

I have just been in the attic of my new house and I have found an infestation of house flys they seen to be in the insulation any suggestions, I have been using fly spray I am on my second tin they are dying but I think I am losing the battle

[Hymie]

The previous owners have disposed of a body somewhere in the loft. Remove the body and the flies will move on.

[Postdog]

A bit strong but I reckon the previous answer is true - there is something there - dead rat, rotting food etc - that is causing it. Find that and get to the bottom of it.

[chas2008]

probably a dead bird....

[Prudie]

A friend of mine had this problem in her new house last year and she was horrified. There were loads of them. I looked it up on the internet for her and they were called cluster flies. Google it and it should give you some advice.