My front porch and back patio are plagued annually by flies (not just 1 or 2, swarms). Some info, both face east, the front patio is covered, while the back is covered by a tarp hung from the roof to the fence for privacy between us and the neighbors. (our large glass sliding doors face each other and we can see directly into each others house, so we put that up for privacy). There are a couple of trees over the back patio, and a couple by the front. I have hung fly traps, sprayed bug sprays nothing seems to keep them away. Whats worse, they come inside whenever a door is opened and then my house is full of flies.

Any help, thoughts or tricks would be appreciated!